Supermassive Black Holes or Their Galaxies? Which Came First?

Supermassive Black Holes or Their Galaxies? Which Came First?:



There’s a supermassive black hole at the center of almost every galaxy in the Universe. How did they get there? What’s the relationship between these monster black holes and the galaxies that surround them?

Every time astronomers look farther out in the Universe, they discover new mysteries. These mysteries require all new tools and techniques to understand. These mysteries lead to more mysteries. What I’m saying is that it’s mystery turtles all the way down.

One of the most fascinating is the discovery of quasars, understanding what they are, and the unveiling of an even deeper mystery, where do they come from?

As always, I’m getting ahead of myself, so first, let’s go back and talk about the discovery of quasars.

Molecular clouds scattered by an intermediate black hole show very wide velocity dispersion in this artist’s impression. This scenario well explains the observational features of a peculiar molecular cloud CO-0.40-0.22. Credit: Keio University

Back in the 1950s, astronomers scanned the skies using radio telescopes, and found a class of bizarre objects in the distant Universe. They were very bright, and incredibly far away; hundreds of millions or even billion of light-years away. The first ones were discovered in the radio spectrum, but over time, astronomers found even more blazing in the visible spectrum.

The astronomer Hong-Yee Chiu coined the term “quasar”, which stood for quasi-stellar object. They were like stars, shining from a single point source, but they clearly weren’t stars, blazing with more radiation than an entire galaxy.

Over the decades, astronomers puzzled out the nature of quasars, learning that they were actually black holes, actively feeding and blasting out radiation, visible billions of light-years away.

But they weren’t the stellar mass black holes, which were known to be from the death of giant stars. These were supermassive black holes, with millions or even billions of times the mass of the Sun.

As far back as the 1970s, astronomers considered the possibility that there might be these supermassive black holes at the heart of many other galaxies, even the Milky Way.

The Whirlpool Galaxy (Spiral Galaxy M51, NGC 5194), a classic spiral galaxy located in the Canes Venatici constellation, and its companion NGC 5195. Credit: NASA/ESA

In 1974, astronomers discovered a radio source at the center of the Milky Way emitting radiation. It was titled Sagittarius A*, with an asterisk that stands for “exciting”, well, in the “excited atoms” perspective.

This would match the emissions of a supermassive black hole that wasn’t actively feeding on material. Our own galaxy could have been a quasar in the past, or in the future, but right now, the black hole was mostly silent, apart from this subtle radiation.

Astronomers needed to be certain, so they performed a detailed survey of the very center of the Milky Way in the infrared spectrum, which allowed them to see through the gas and dust that obscures the core in visible light.

They discovered a group of stars orbiting Sagittarius A-star, like comets orbiting the Sun. Only a black hole with millions of times the mass of the Sun could provide the kind of gravitational anchor to whip these stars around in such bizarre orbits.

Further surveys found a supermassive black hole at the heart of the Andromeda Galaxy, in fact, it appears as if these monsters are at the center of almost every galaxy in the Universe.

But how did they form? Where did they come from? Did the galaxy form first, and cause the black hole to form at the middle, or did the black hole form, and build up a galaxy around them?

Until recently, this was actually still one of the big unsolved mysteries in astronomy. That said, astronomers have done plenty of research, using more and more sensitive observatories, worked out their theories, and now they’re gathering evidence to help get to the bottom of this mystery.

Astronomers have developed two models for how the large scale structure of the Universe came together: top down and bottom up.

In the top down model, an entire galactic supercluster formed all at once out of a huge cloud of primordial hydrogen left over from the Big Bang. A supercluster’s worth of stars.

As the cloud came together it, it spun up, kicking out smaller spirals and dwarf galaxies. These could have combined later on to form the more complex structure we see today. The supermassive black holes would have formed as the dense cores of these galaxies as they came together.

Hubble image of Messier 54, a globular cluster located in the Sagittarius Dwarf Galaxy. Credit: ESA/Hubble & NASA

If you want to wrap your mind around this, think of the stellar nursery that formed our Sun and a bunch of other stars. Imagine a single cloud of gas and dust forming multiple stars systems within it. Over time, the stars matured and drifted away from each other.

That’s top down. One big event that leads to the structure we see today.

In the bottom up model, pockets of gas and dust collected together into larger and larger masses, eventually forming dwarf galaxies, and even the clusters and superclusters we see today. The supermassive black holes at the heart of galaxies were grown from collisions and mergers between black holes over eons.

In fact, this is actually how astronomers think the planets in the Solar System formed. By pieces of dust attracting one another into larger and larger grains until the planet-sized objects formed over millions of years.

Bottom up, small parts coming together.

Shortly after the Big Bang, the entire Universe was incredibly dense. But it wasn’t the same density everywhere. Tiny quantum fluctuations in density at the beginning evolved over billions of years of expansion into the galactic superclusters we see today.

Colliding galaxies can force the supermassive black holes in their cores together (NCSA)

I want to stop and let this sink into your brain for a second. There were microscopic variations in density in the early Universe. And these variations became the structures hundreds of millions of light-years across we see today.


Imagine the two forces at play as the expansion of the Universe happened. On the one hand, you’ve got the mutual gravity of the particles pulling one another together. And on the other hand, you’ve got the expansion of the Universe separating the particles from one another. The size of the galaxies, clusters and superclusters were decided by the balance point of those opposing forces.

If small pieces came together, then you’d get that bottom up formation. If large pieces came together, you’d get that top down formation.

When astronomers look out into the Universe at the largest scales, they observe clusters and superclusters as far as they can see – which supports the top down model.

On the other hand, observations show that the first stars formed just a few hundred million years after the Big Bang, which supports bottom up.

So the answer is both?

No, the most modern observations give the edge to the bottom up processes.

The key is that gravity moves at the speed of light, which means that the gravitational interactions between particles spreading away from each other needed to catch up, going the speed of light.

In other words, you wouldn’t get a supercluster’s worth of material coming together, only a star’s worth of material. But these first stars were made of pure hydrogen and helium, and could grow much more massive than the stars we have today. They would live fast and die in supernova explosions, creating much more massive black holes than we get today.

This illustration shows the final stages in the life of a supermassive star that fails to explode as a supernova, but instead implodes to form a black hole. Credit: NASA/ESA/P. Jeffries (STScI)

The first protogalaxies came together, collecting together these first monster black holes and the massive stars surrounding them. And then, over millions and billions of years, these black holes merged again and again, accumulating millions and even billions of times the mass of the Sun. This was how we got the modern galaxies we see today.

There was a recent observation that supports this conclusion. Earlier this year, astronomers announced the discovery of supermassive black holes at the center of relatively tiny galaxies. In our own Milky Way, the supermassive black hole is 4.1 million times the mass of the Sun, but accounts for only .01% of the galaxy’s total mass.

But astronomers from the University of Utah found two ultra compact galaxies with black holes of 4.4 million and 5.8 million times the mass of the Sun respectively. And yet, the black holes account for 13 and 18 percent of the mass of their host galaxies.

The thinking is that these galaxies were once normal, but collided with other galaxies earlier on in the history of the Universe, were stripped of their stars and then were spat out to roam the cosmos.

They’re the victims of those early merging events, evidence of the carnage that happened in the early Universe when the mergers were happening.

We always talk about the unsolved mysteries in the Universe, but this is one that astronomers are starting to puzzle out.

It seems most likely that the structure of the Universe we see today formed bottom up. The first stars came together into protogalaxies, dying as supernova to form the first black holes. The structure of the Universe we see today is the end result of billions of years of formation and destruction. With the supermassive black holes coming together over time.

Once telescopes like James Webb get to work, we should be able to see these pieces coming together, at the very edge of the observable Universe.

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Original enclosures:

322SupermassiveBlackHolesOrGalaxies.mp4

The Orbit of Earth will be Hiding Earth 2.0

The Orbit of Earth will be Hiding Earth 2.0:

In the hunt for extra-solar planets, astronomers and enthusiasts can be forgiven for being a bit optimistic. In the course of discovering thousands of rocky planets, gas giants, and other celestial bodies, is it too much to hope that we might someday find a genuine Earth-analog? Not just an “Earth-like” planet (which implies a rocky body of comparable size) but an actual Earth 2.0?

This has certainly been one of the goals of exoplanet-hunters, who are searching nearby star systems for planets that are not only rocky, but orbit within their star’s habitable zone, show signs of an atmosphere and have water on their surfaces. But according to a new study by Alexey G. Butkevich – a astrophysicist from the Pulkovo Observatory in St. Petersburg, Russia – our attempts to discover Earth 2.0 could be hindered by Earth itself!

Butkevich’s study, titled “Astrometric Exoplanet Detectability and the Earth Orbital Motion“, was recently published in the Monthly Notices of the Royal Astronomical Society. For the sake of his study, Dr. Butkevich examined how changes in the Earth’s own orbital position could make it more difficult to conduct measurements of a star’s motion around its system’s barycenter.

Artist’s impression of how an Earth-like planet might look from space. Credit: ESO.

This method of exoplanet detection, where the motion of a star around the star system’s center of mass (barycenter), is known as the Astrometic Method. Essentially, astronomers attempt to determine if the presence of gravitational fields around a star (i.e. planets) are causing the star to wobble back and forth. This is certainly true of the Solar System, where our Sun is pulled back and forth around a common center by the pull of all its planets.

In the past, this technique has been used to identify binary stars with a high degree of precision. In recent decades, it has been considered as a viable method for exoplanet hunting. This is no easy task since the wobbles are rather difficult to detect at the distances involved. And until recently, the level of precision required to detect these shifts was at the very edge of instrument sensitivity.

This is rapidly changing, thanks to improved instruments that allow for accuracy down to the microarcsecond. A good example of this is the ESA’s Gaia spacecraft, which was deployed in 2013 to catalog and measure the relative motions of billions of stars in our galaxy. Given that it can conduct measurements at 10 microarcseconds, it is believed that this mission could conduct astrometric measurements for the sake of finding exoplanets.

But as Butkevich explained, there are other problems when it comes to this method. “The standard astrometric model is based on the assumption that stars move uniformly relative to the solar system barycentre,” he states. But as he goes on to explain, when examining the effects of Earth’s orbital motion on astrometric detection, there is a correlation between the Earth’s orbit and the position of a star relative to its system barycenter.

Kepler-22b, an exoplanet with an Earth-like radius that was discovery within the habitable zone of its host star. Credit: NASA

To put it another way, Dr. Butkevich examined whether or not the motion of our planet around the Sun, and the Sun’s motion around its center of mass, could have a cancelling effect on parallax measurements of other stars. This would effectively make any measurements of a star’s motion, designed to see if there were any planets orbiting it, effectively useless. Or as Dr. Butkevich stated in his study:

“It is clear from simple geometrical considerations that in such systems the orbital motion of the host star, under certain conditions, may be observationally close to the parallactic effect or even indistinguishable from it. It means that the orbital motion may be partially or fully absorbed by the parallax parameters.”

This would be especially true of systems where the orbital period of a planet was one year, and which had an orbit that placed it close to the Sun’s ecliptic – i.e. like Earth’s own orbit! So basically, astronomers would not be able to detect Earth 2.0 using astrometric measurements, because Earth’s own orbit and the Sun’s own wobble would make detection close to impossible.

As Dr. Butkevich states in his conclusions:

“We present an analysis of effects of the Earth orbital motion on astrometric detectability of exoplanetary systems. We demonstrated that, if period of a planet is close to one year and its orbital plane is nearly parallel to the ecliptic, orbital motion of the host may be entirely or partially absorbed by the parallax parameter. If full absorption occurs, the planet is astrometrically undetectable.”

Future surveys for exoplanets could be complicated by the Sun’s own motion around its barycenter. Credit: NASA

Luckily, exoplanet-hunters have a myriad of other methods too choose from, including direct and indirect measurements. And when it comes to spotting planets around neighboring stars, two of the most effective involve measuring Doppler shifts in stars (aka. the Radial Velocity Method) and dips in a star’s brightness (aka. the Transit Method).

Nevertheless, these methods suffer from their own share of drawbacks, and knowing their limitations is the first step in refining them. In that respect, Dr. Butkevich’s study has echoes of heliocentrism and relativity, where we are reminded that our own reference point is not fixed in space, and can influence our observations.

The hunt for exoplanets is also expected to benefit greatly from deployment of next-generation instruments like the James Webb Space Telescope, the Transiting Exoplanet Survey Satellite (TESS), and others.

Further Reading: arXiv

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Second Fastest Pulsar Spins 42,000 Times a Minute

Second Fastest Pulsar Spins 42,000 Times a Minute:

Pulsars are what remains when a massive star undergoes gravitational collapse and explodes in a supernova. These remnants (also known as neutron stars) are extremely dense, with several Earth-masses crammed into a space the size of a small country. They also have powerful magnetic fields, which causes them to rotate rapidly and emit powerful beams of gamma rays or x-rays – which lends them the appearance of a lighthouse.

In some cases, pulsars spin especially fast, taking only milliseconds to complete a single rotation. These “millisecond pulsars” remain a source of mystery for astronomers. And after following up on previous observations, researchers using the Low Frequency Array (LOFAR) radio telescope in the Netherlands identified a pulsar (PSR J0952?0607) that spins more than 42,000 times per minute, making it the second-fastest pulsar ever discovered.

The study which described their findings, titled “LOFAR Discovery of the Fastest-spinning Millisecond Pulsar in the Galactic Field“, recently appeared in The Astrophysical Journal Letters. Led by Dr. Cees Bassa, an astrophysicist from the University of Utrecht and the Netherlands Institute for Radio Astronomy (ASTRON), the team conducted follow-up observations of PSR J0952?0607, a millisecond pulsar located 3,200 to 5,700 light-years away.

An all-sky view in gamma ray light made with the Fermi gamma ray space telescope. Credit: NASA/DOE/International LAT Team

This study was part of an ongoing LOFAR survey of energetic sources originally identified by NASA’s Fermi Gamma-ray space telescope. The purpose of this survey was to distinguish between the gamma-ray sources Fermi detected, which could have been caused by neutron stars, pulsars, supernovae or the regions around black holes. As Elizabeth Ferrara, a member of the discovery team at NASA’s Goddard Space Center, explained in a NASA press release:

“Roughly a third of the gamma-ray sources found by Fermi have not been detected at other wavelengths. Many of these unassociated sources may be pulsars, but we often need follow-up from radio observatories to detect the pulses and prove it. There’s a real synergy across the extreme ends of the electromagnetic spectrum in hunting for them.”

Their follow-up observations indicated that this particular source was a pulsar that spins at a rate of 707 revolutions (Hz) per second, which works out to 42,000 revolutions per minute. This makes it, by definition, a millisecond pulsar. The team also confirmed that it is about 1.4 Solar Masses and is orbited every 6.4 hours by a companion star that has been stripped down to less than 0.05 Jupiter masses.

The presence of this lightweight companion is a further indication of how the spin of this pulsar became so rapid. Over time, matter would have been stripped away from the star, gradually accreting onto PSR J0952?0607. This would not only raise its spin rate but also greatly increase its electromagnetic emissions. The process continues to this day, with the star becoming increasingly smaller as the pulsar becomes more energetic.

Artist’s impression of a pulsar siphoning material from a companion star. Credit: NASA

Because of the nature of this relationship (which can only be described as “cannibalistic”), systems like PSR J0952?0607 are often called “black widow” or “redback” pulsars. Most of these systems were found by following up on sources identified by the Fermi mission, since the process has been known to result in a considerable amount of electromagnetic radiation being released.

Beyond the discovery of this record-setting pulsar, the LOFAR discovery could also be an indication that there is a new population of ultra-fast spinning pulsars in our Universe. As Dr. Bassa explained:

“LOFAR picked up pulses from J0952 at radio frequencies around 135 MHz, which is about 45 percent lower than the lowest frequencies of conventional radio searches. We found that J0952 has a steep radio spectrum, which means its radio pulses fade out very quickly at higher frequencies. It would have been a challenge to find it without LOFAR.”

The fastest spinning pulsar known, PSR J1748-2446ad, spins just slightly faster than PSR J0952?0607 – reaching a rate of nearly 43,000 rpm (or 716 revolutions per second). But some theorists think that pulsars could spin as fast as 72,000 rpm (almost twice as fast) before breaking up. This remains a theory, since rapidly-spinning pulsars are rather difficult to detect.



But with the help of instrument like LOFAR, that could be changing. For instance, both PSR J1748-2446ad and PSR J0952?0607 were shown to have steep spectra – much like radio galaxies and Active Galactic Nuclei.  The same was true of J1552+5437, another millisecond pular detected by LOFAR which spins at 25,000 rpm.

As Ziggy Pleunis – a doctoral student at McGill University in Montreal and a co-author on the study – indicated, this could be a sign that the fastest-spinning pulsars are just waiting to be found.

“There is growing evidence that the fastest-spinning pulsars tend to have the steepest spectra,” he said. “Since LOFAR searches are more sensitive to these steep-spectrum radio pulsars, we may find that even faster pulsars do, in fact, exist and have been missed by surveys at higher frequencies.”

As with many other areas of astronomical research, improvements in instrumentation and methodology are allowing for new and exciting discoveries. As expected, some of the things we are finding are forcing astronomers to rethink more than a few previously-held assumptions about the nature and limits of certain phenomena.

Be sure to enjoy this NASA video that explains “black widow” pulsars and the ongoing search to find them:



Further Reading: NASA, Astrophysical Journal Letters

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Chinese Astronomers Spot Two New Hypervelocity Stars

Chinese Astronomers Spot Two New Hypervelocity Stars:

Most stars in our galaxy behave predictably, orbiting around the center of the Milky Way at speeds of about 100 km/s (62 mi/s). But some stars achieve velocities that are significantly greater, to the point that they are even able to escape the gravitational pull of the galaxy. These are known as hypervelocity stars (HVS), a rare type of star that is believed to be the result of interactions with a supermassive black hole (SMBH).

The existence of HVS is something that astronomers first theorized in the late 1980s, and only 20 have been identified so far. But thanks to a new study by a team of Chinese astronomers, two new hypervelocity stars have been added to that list. These stars, which have been designated LAMOST-HVS2 and LAMOST-HVS3, travel at speeds of up to 1,000 km/s (620 mi/s) and are thought to have originated in the center of our galaxy.

The study which describes the team’s findings, titled “Discovery of Two New Hypervelocity Stars From the LAMOST Spectroscopic Surveys“, recently appeared online. Led by Yang Huang of the South-Western Institute for Astronomy Research at Yunnan University in Kunming, China, the team relied on data from Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) to detect these two new hypervelocity stars.

Footprint of the LAMOST pilot survey and the first three years’ general survey. Credit: LAMOST

Astronomers estimates that only 1000 HVS exist within the Milky Way. Given that there are as many as 200 billion stars in our galaxy, that’s just 0.0000005 % of the galactic population. While these stars are thought to originate in the center of our galaxy – supposedly as a result of interaction with our SMBH, Sagittarius A* – they manage to travel pretty far, sometimes even escaping our galaxy altogether.

It is for this very reason that astronomers are so interested in HVS. Given their speed, and the vast distances they can cover, tracking them and creating a database of their movements could provide constraints on the shape of the dark matter halo of our galaxy. Hence why Dr. Huang and his colleagues began sifting through LAMOST data to find evidence of new HVS.

Located in Hebei Province, northwestern China, the LAMOST observatory is operated by the Chinese Academy of Sciences. Over the course of five years, this observatory conducted a spectroscopic survey of 10 million stars in the Milky Way, as well as millions of galaxies. In June of 2017, LAMOST released its third Data Release (DR3), which included spectra obtained during the pilot survey and its first three years’ of regular surveys.

Containing high-quality spectra of 4.66 million stars and the stellar parameters of an additional 3.17 million, DR3 is currently the largest public spectral set and stellar parameter catalogue in the world. Already, LAMOST data had been used to identify one hypervelocity star, a B1IV/V-type (main sequence blue subgiant/subdwarf) star that was 11 Solar Masses, 13490 times as bright as our Sun, and had an effective temperature of 26,000 K (25,727 °C; 46,340 °F).

Artist’s impression of hypervelocity stars (HVSs) speeding through the Galaxy. Credit: ESA

This HVS was designated LAMOST-HSV1, in honor of the observatory. After detecting two new HVSs in the LAMOST data, these stars were designated as LAMOST-HSV2 and LAMOST-HSV3. Interestingly enough, these newly-discovered HVSs are also main sequence blue subdwarfs – or a B2V-type and B7V-type star, respectively.

Whereas HSV2 is 7.3 Solar Masses, is 2399 times as luminous as our Sun, and has an effective temperature of 20,600 K (20,327 °C; 36,620 °F), HSV3 is 3.9 Solar Masses, is 309 times as luminous as the Sun, and has an effective temperature of 14,000 K (24,740 °C; 44,564 °F). The researchers also considered the possible origins of all three HVSs based on their spatial positions and flight times.

In addition to considering that they originated in the center of the Milky Way, they also consider alternate possibilities. As they state in their study:

“The three HVSs are all spatially associated with known young stellar structures near the GC, which supports a GC origin for them. However, two of them, i.e. LAMOST-HVS1 and 2, have life times smaller than their flight times, indicating that they do not have enough time to travel from the GC to the current positions unless they are blue stragglers (as in the case of HVS HE 0437-5439). The third one (LAMOST-HVS3) has a life time larger than its flight time and thus does not have this problem.

In other words, the origins of these stars is still something of a mystery. Beyond the idea that they were sped up by interacting with the SMBH at the center of our galaxy, the team also considered other possibilities that have suggested over the years.

Artist’s impression of the ESA’s Gaia spacecraft, looking into the heart of the Milky Way  Galaxy. Credit: ESA/ATG medialab/ESO/S. Brunier

As they state in these study, these “include the tidal debris of an accreted and disrupted dwarf galaxy (Abadi et al. 2009), the surviving companion stars of Type Ia supernova (SNe Ia) explosions (Wang & Han 2009), the result of dynamical interaction between multiple stars (e.g, Gvaramadze et al. 2009), and the runaways ejected from the Large Magellanic Cloud (LMC), assuming that the latter hosts a MBH (Boubert et al. 2016).”

In the future, Huang and his colleagues indicate that their study will benefit from additional information that will be provided by the ESA’s Gaia mission, which they claim will shed additional light on how HVS behave and where they come from. As they state in their conclusions:

“The upcoming accurate proper motion measurements by Gaia should provide a direct constraint on their origins. Finally, we expect more HVSs to be discovered by the ongoing LAMOST spectroscopic surveys and thus to provide further constraint on the nature and ejection mechanisms of HVSs.”

Further Reading: arXiv

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Detection of Mineral on Mars Bolsters Argument that Mars was Once Habitable

Detection of Mineral on Mars Bolsters Argument that Mars was Once Habitable:

It has become a well-known scientific fact that billions of years ago, Mars once had a thicker atmosphere and liquid water on its surface. Scientists have also discovered that it was the gradual loss of this atmosphere, between 4.2 and 3.7 billion years ago, that caused Mars to go from being a warmer, wetter environment to the dry, freezing environment it is today.

Despite the existence of both a thicker atmosphere and water, questions remain as to whether or not Mars was truly habitable in the past. According to a new study from a team of researchers from the Los Alamos National Laboratory (LANL), the discovery of a specific mineral (boron) has added weight to the argument that Mars was once a potentially life-bearing world.

The study, titled “In situ detection of boron by ChemCam on Mars“, was recently published in the scientific journal Geophysical Research Letters. For the sake of this study, the LANL research team consulted data collected by the  Chemistry and Camera (ChemCam) instrument aboard the Curiosity rover, which showed evidence of boron on the surface of Mars.

Mars, as it may have looked 4.2 billion years ago (left) and today (right). Credit: Kevin Gill

Boron, an element which is created by cosmic rays and is relatively rare in the Solar System, is necessary for the creation of ribonucleic acid – which is present in all forms of modern life. Essentially, RNA requires a key ingredient to form, which is a sugar called ribose. Like all sugars, ribose is highly unstable and decomposes quickly in water. As such, it needs another element to stabilize it, which is where boron comes into play.

As Patrick Gasda, a postdoctoral researcher at the Los Alamos National Laboratory and lead author on the paper, explained in a LANL press statement:

“Because borates may play an important role in making RNA – one of the building blocks of life – finding boron on Mars further opens the possibility that life could have once arisen on the planet. Borates are one possible bridge from simple organic molecules to RNA. Without RNA, you have no life. The presence of boron tells us that, if organics were present on Mars, these chemical reactions could have occurred.”

When boron is dissolved in water (which, as noted, Mars once had in abundance) it becomes borate. This compound (when combined with ribose) would act as a stabilizing agent, keeping the sugar together long enough so that RNA can form. As Gasda explained, “We detected borates in a crater on Mars that’s 3.8 billion years old, younger than the likely formation of life on Earth.”

Artist rendition of how the “lake” at Gale Crater on Mars may have looked millions of years ago. Credit and copyright: Kevin Gill.

The boron was detected by Curiosity’s laser-shooting ChemCam instrument, which was developed by the LANL in conjunction with France’s space agency, the National Center of Space Studies (CNES). It detected the element in veins of calcium sulfate minerals located in the Gale Crater, which means that boron was present in Mars’ groundwater and was preserved with other minerals when the water dissolved, leaving behind rich mineral veins.

This provides further evidence that the lake that is now known to have once filled the Gale Crater could have had life in it. During the time period in question, this lake would have experienced temperatures ranging from from 0 to 60 ° C (32 to 140 °F) and had a pH level that would have been neutral-to-alkaline. It also means that on ancient Mars, the conditions necessary for life would have existed, and independent of Earth to boot.

This is just one of many findings Curiosity has made related to the composition of Martian rocks. Since it touched down in the Gale Crater in 2012, the rover has been gathering chemical evidence of the ancient lake that once existed there, as well as geological evidence that has been preserved by sedimentary deposits. As the rover began to scale the slope of Mount Sharp, the composition of the surface began to change.

Whereas samples taken from the crater floor tended to contain more in the way of clays, samples collected higher up Mount Sharp contained more boron. These and other chemical traces are indications of how conditions under which sediments were deposited changed over time. Analysis conducted of the mountain’s layers has also showed how the movement of groundwater through these layers of sediment altered and transported elements (like boron).

MRO image of Gale Crater illustrating the landing location and trek of the Rover Curiosity. Credits: NASA/JPL, illustration, T.Reyes

All of this is providing a picture of how Mars’ environment changed over the course of billions of years and affected the planet’s potential favorability for microbial life. And while scientists have a general picture of how Mars underwent a very significant transition billions of years ago, whether or not Martian life ever existed remains unknown.

The main goal of the Curiosity mission was to determine whether the area ever offered a habitable environment. Thanks to evidence of past water and the discovery of minerals like boron, this has been confirmed. In the coming years, the deployment of the Mars 2020 rover is expected to follow-up on these findings and shed more light on Mars’ case for past habitability.

Once it reaches the surface, the Mars 2020 rover – which relies on much of the same technology as Curiosity – will use an instrument called the Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC). Also developed by the LANL, this “SuperCam” instrument will use spectrometers, a laser and a camera to search for organics and minerals that could indicate the existence of past microbial life.

If there is still preserved evidence of life to be found on Mars or – fingers crossed! – microbial life still exists there today, we can expect to find it before long. If that should be the case, human beings will finally know with certainty that life evolved on a planet other than Earth, and perhaps independent of it!

Further Reading: LANL, Geophysical Research Letters

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New Study Claims that TRAPPIST-1 Could Also Have Gas Giants

New Study Claims that TRAPPIST-1 Could Also Have Gas Giants:

In February of 2017, NASA scientists announced the existence of seven terrestrial (i.e. rocky) planets within the TRAPPIST-1 star system. Since that time, the system has been the focal point of intense research to determine whether or not any of these planets could be habitable. At the same time, astronomers have been wondering if all of the system’s planets are actually accounted for.

For instance, could this system have gas giants lurking in its outer reaches, as many other systems with rocky planets (for instance, ours) do? That was the question that a team of scientists, led by researchers from the Carnegie Institute of Science, sought to address in a recent study. According to their findings, TRAPPIST-1 may be orbited by gas giants at a much-greater distance than its seven rocky planets.

The study, titled “Astrometric Constraints on the Masses of Long-Period Gas Giant Planets in the TRAPPIST-1 Planetary System“, recently appeared in The Astronomical Journal. As they indicate in their study, the team relied on follow-up observations made of TRAPPIST-1 over a period of five years (from 2011 to 2016) using the du Pont telescope at the Las Campanas Observatory in Chile.



Using these observations, they sought to determine if TRAPPIST-1 could have previously-undetected gas giants orbiting within the outer reaches of the system. As Dr. Alan Boss – an astrophysicist and planetary scientist with the Carnegie Institute’s Department of Terrestrial Magnetism and the lead author on the paper – explained in a Carnegie press statement:

“A number of other star systems that include Earth-sized planets and super-Earths are also home to at least one gas giant. So, asking whether these seven planets have gas giant siblings with longer-period orbits is an important question.”

For years, Boss has conducted an exoplanet-hunting survey with the co-authors of the study – Alycia J. Weinberger, Ian B. Thompson, et al. – known as the Carnegie Astrometric Planet Search. This survey relies on the Carnegie Astrometric Planet Search Camera (CAPSCam), an instrument on the du Pont telecope that searches for extrasolar planets using the astrometric method.

This indirect method of exoplanet-hunting determines the presence of planets around a star by measuring the wobble of this host star around the system’s center of mass (aka. its barycenter). Using CAPSCam, Boss and his colleagues relied on several years of observations of TRAPPIST-1 to determine the upper mass limits for any potential gas giants orbiting in the system.

From this, they concluded that planets that were up to 4.6 Jupiter Masses could orbit the star with a period of a year. In addition, they found that planets up to 1.6 Jupiter Masses could orbit the star with 5-year periods. In other words, it is possible that TRAPPIST-1 has some long-period gas giants orbiting its outer reaches, much in the same way that long-period gas giants exists beyond the orbit of Mars in the Solar System.

Three of the TRAPPIST-1 planets – TRAPPIST-1e, f and g – dwell in their star’s so-called “habitable zone. CreditL NASA/JPL

If true, the existence of these giant planets could resolve an ongoing debate about the formation of the Solar System’s gas giants. According to the most-widely accepted theory about the Solar System’s formation (i.e. Nebular Hypothesis), the Sun and planets were born of a nebula of gas and dust. After this cloud experienced gravitational collapse at the center, forming the Sun, the remaining dust and gas flattened out into a disk surrounding it.

Earth and the other terrestrial planets (Mercury, Venus and Mars) all formed closer to the Sun from the accretion of silicate minerals and metals. As for the gas giants, there are some competing theories as to how they formed. In one scenario, known as the Core Accretion theory, the gas giants also began accreting from solid materials (forming a solid core) which became large enough to attract an envelop of surrounding gas.

A competing explanation – known as the Disk Instability theory – claims that they formed when the disk of gas and dust took on a spiral arm formation (similar to a galaxy). These arms then began to increase in mass and density, forming clumps that rapidly coalesced to form baby gas giants. Using computational models, Boss and his colleagues considered both theories to see if gas giants could form around a low-mass star like TRAPPIST-1.

Whereas Core Accretion was not likely, the Disk Instability theory indicated that gas giants could form around TRAPPIST-1 and other low-mass red dwarf stars. As such, this study provides a theoretical framework for the existence of gas giants in red dwarf star systems that are already known to have rocky planets. This is certainly encouraging news for exoplanet-hunters given the spate of rocky planets have been found orbiting red dwarfs of late.



Aside from TRAPPIST-1, these include the closest exoplanet to the Solar System (Proxima b), as well as LHS 1140b, Gliese 581g, Gliese 625b, and Gliese 682c. But as Boss also noted, this research is still in its infancy, and much more research and discussion needs to take place before anything can be said conclusively. Luckily, studies such as this one are helping to open to the door to such studies and discussions.

“Gas giant planets found on long-period orbits around TRAPPIST-1 could challenge the core accretion theory, but not necessarily the disk instability theory,” said Boss. “There is a lot of space for further investigation between the longer-period orbits we studied here and the very short orbits of the seven known TRAPPIST-1 planets.”

Boss and his team also assert that continued observations with the CAPSCam and further refinements in its data analysis pipeline will either detect any long-period planets, or put an even tighter constraint on their upper mass limits. And of course, the deployment of next-generation infrared telescopes, such as the James Webb Space Telescope, will assist in the hunt for gas giants around red dwarf stars.

Further Reading: Carnegie Institute of Science, The Astronomical Journal

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X-ray Study Shows Older Stars May be More Supportive to Life

X-ray Study Shows Older Stars May be More Supportive to Life:

Astronomers have long understood that there is a link between a star’s magnetic activity and the amount of X-rays it emits. When stars are young, they are magnetically active, due to the fact that they undergo rapid rotation. But over time, the stars lose rotational energy and their magnetic fields weaken. Concurrently, their associated X-ray emissions also begin to drop.

Interestingly, this relationship between a star’s magnetic activity and X-ray emissions could be a means for finding potentially-habitable star systems. Hence why an international team led by researchers from Queen’s University Belfast conducted a study where they cataloged the X-ray activity of 24 Sun-like stars. In so doing, they were able to determine just how hospitable these star systems could be to life.

This study, titled “An Improved Age-Activity Relationship for Cool Stars Older than a Gigayear“, recently appeared in the Monthly Notices of the Royal Astronomical Society. Led by Rachel Booth, a PhD student from the Astrophysics Research Center at Queen’s University Belfast, the team used data from NASA’s Chandra X-ray Observatory and the ESA’s XMM-Newton to examine how the X-ray brightness of 24 Sun-like stars changed over time.

This artist’s impression shows the magnetar in the very rich and young star cluster Westerlund 1. Credit: ESO/L. Calçada

To understand how stellar magnetic activity (and hence, X-ray activity) changes over time, astronomers require accurate age assessments for many different stars. This has been difficult in the past, but thanks to mission like NASA’s Kepler Space Observatory and the ESA’s Convection, Rotation and planetary Transits (CoRoT) mission, new and precise age estimates have become available in recent years.

Using these age estimates, Booth and her colleagues relied on data from the Chandra X-ray observatory and the XMM-Newton obervatory to examine 24 nearby stars. These stars were all similar in mass to our Sun (a main sequence G-type yellow dwarf star) and at least 1 billion years of age. From this, they determined that there was a clear link between the star’s age and their X-ray emissions. As they state in their study:

“We find 14 stars with detectable X-ray luminosities and use these to calibrate the age-activity relationship. We find a relationship between stellar X-ray luminosity, normalized by stellar surface area, and age that is steeper than the relationships found for younger stars…”

In short, of the 24 stars in their sample, the team found that 14 had X-ray emissions that were discernible. From these, they were able to calculate the star’s ages and determine that there was a relationship between their longevity and luminosity. Ultimately, this demonstrated that stars like our Sun are likely to emit less high-energy radiation as they exceed 1 billion years in age.



And while the reason for this is not entirely clear, astronomers are currently exploring various possible causes. One possibility is that for older stars, the reduction in spin rate happens more quickly than it does for younger stars. Another possibility is that the X-ray brightness declines more quickly for older, more slowly-rotating stars than it does for younger, faster ones.

Regardless of the cause, the relationship between a star’s age and its X-ray emissions could provide astronomers and exoplanet hunters with another tool for gauging the possible habitability of a system. Wherever a G-type or K-type star is to be found, knowing the age of the star could help place constraints on the potential habitability of any planets that orbit it.

Further Reading: Chandra, MNRAS

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Exoplanet-Hunting Aliens Could Be Looking at Earth Right Now!

Exoplanet-Hunting Aliens Could Be Looking at Earth Right Now!:

In the past few decades, the search for extra-solar planets has turned up a wealth of discoveries. Between the many direct and indirect methods used by exoplanet-hunters, thousands of gas giants, rocky planets and other bodies have been found orbiting distant stars. Aside from learning more about the Universe we inhabit, one of the main driving forces behind these efforts has been the desire to find evidence of Extra-Terrestrial Intelligence (ETI).

But suppose there are ETIs out there that are are also looking for signs of intelligence other than their own? How likely would they be to spot Earth? According to a new study by a team of astrophysicists from Queen’s University Belfast and the Max Planck Institute for Solar System Research in Germany, Earth would be detectable (using existing technology) from several star systems in our galaxy.

This study, titled “Transit Visibility Zones of the Solar System Planet“, was recently published in the Monthly Notices of the Royal Astronomical Society. Led by Robert Wells, a PhD student at the Astrophysics Research Center at Queen’s University Belfast, the team considered whether or not Earth would be detectable from other star systems using the Transit Method.

Diagram of a planet (e.g. the Earth, blue) transiting in front of its host star (e.g. the Sun, yellow). The lower black curve shows the brightness of the star noticeably dimming over the transit event, when the planet is blocking some of the light from the star. Credit: R. Wells.

This method consists of astronomers observing stars for periodic dips in brightness, which are attributed to planets passing (i.e. transiting) between them and the observer. For the sake of their study, Wells and his colleagues reversed the concept in order to determine if Earth would be visible to any species conducting observations from vantage points beyond our Solar System.

To answer this question, the team looked for parts of the sky from which one planet would be visible crossing the face of the Sun – aka. “transit zones”. Interestingly enough, they determined that the terrestrial planets that are closer to the Sun (Mercury, Venus, Earth and Mars) would easier to detect than the gas and ice giants – i.e.  Jupiter, Saturn, Uranus and Neptune.

While considerably larger, the gas/ice giants would be more difficult to detect using the transit method because of their long-period orbits. From Jupiter to Neptune, these planets take about 12 to 165 years to complete a single orbit! But more important than that is the fact that they orbit the Sun at much greater distances than the terrestrial planets. As Robert Wells indicated in a Royal Astronomical Society press statement:

”Larger planets would naturally block out more light as they pass in front of their star. However the more important factor is actually how close the planet is to its parent star – since the terrestrial planets are much closer to the Sun than the gas giants, they’ll be more likely to be seen in transit.”

How the transit zone of a Solar System planet is projected out from the Sun. The observer on the green exoplanet is situated in the transit zone and can therefore see transits of the Earth. Credit: R. Wells

Ultimately, what the team found was that at most, three planets could be observed from anywhere outside of the Solar System, and that not all combinations of these three planets was possible. For the most part, an observer would see only planet making a transit, and it would most likely be a rocky one. As Katja Poppenhaeger, a lecturer at the School of Mathematics and Physics at Queen’s University Belfast and a co-author of the study, explained:

“We estimate that a randomly positioned observer would have roughly a 1 in 40 chance of observing at least one planet. The probability of detecting at least two planets would be about ten times lower, and to detect three would be a further ten times smaller than this.”

What’s more, the team identified sixty-eight worlds where observers would be able to see one or more of the Solar planets making transits in front of the Sun. Nine of these planets are ideally situated to observe transits of the Earth, though none of them have been deemed to be habitable. These planets include HATS-11 b, 1RXS 1609 b, LKCA 15 b, WASP-68 b, WD 1145+017 b, and four planets in the WASP-47 system (b, c, d, e).

On top of that, they estimated (based on statistical analysis) that there could be as many as ten undiscovered and potentially habitable worlds in our galaxy which would be favorably located to detect Earth using our current level of technology. This last part is encouraging since, to date, not a single potentially habitable planet has been discovered where Earth could be seen making transits in front of the Sun.

Image showing where transits of our Solar System planets can be observed. Each line represents where one of the planets could be seen to transit, with the blue line representing Earth; an observer located here could detect us. Credit: 2MASS/A. Mellinger/R. Wells.

The team also indicated that further discoveries made by the Kepler and K2 missions will reveal additional exoplanets that have “a favorable geometric perspective to allow transit detections in the Solar System”. In the future, Wells and his team plan to study these transit zones to search for exoplanets, which will hopefully reveal some that could also be habitable.

One of the defining characteristics in the Search for Extra-Terrestrial Intelligence (SETI) has been the act of guessing about what we don’t know based on what we do. In this respect, scientists are forced to consider what extra-terrestrial civilizations would be capable of based on what humans are currently capable of. This is similar to how our search for potentially habitable planets is limited since we know of only one where life exists (i.e. Earth).

While it might seem a bit anthropocentric, it’s actually in keeping with our current frame of reference. Assuming that intelligent species could be looking at Earth using the same methods we do is like looking for planets that orbit within their star’s habitable zones, have atmospheres and liquid water on the surfaces.

In other words, it’s the “low-hanging fruit” approach. But thanks to ongoing studies and new discoveries, our reach is slowly extending further!

Further Reading: RAS, MNRAS

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Juno Missions Make Mysterious Finds about Auroras on Jupiter

Juno Missions Make Mysterious Finds about Auroras on Jupiter:

Even after decades of study, Jupiter’s atmosphere continues to be something of a mystery to scientists. Consistent with the planet’s size, its atmosphere is the largest in the Solar System, spanning over 5,000 km (3,000 mi) in altitude and boasting extremes in temperature and pressure. On top of that, the planet’s atmosphere experiences the most powerful auroras in the Solar System.

Studying this phenomena has been one of the main goals of the Juno probe, which reached Jupiter on July 5th, 2016. However, after analyzing data collected by the probe’s instruments, scientists at Johns Hopkins University Applied Physics Laboratory (JHUAPL) were surprised to find that Jupiter’s powerful magnetic storms do not have the same source as they do on Earth.

The study which details these findings, “Discrete and Broadband Electron Acceleration in Jupiter’s Powerful Aurora“, recently appeared in the scientific journal Nature. Led by Barry Mauk, a scientist with the JHUAPL, the team analyzed data collected by Juno’s Ultraviolet Spectrograph (UVS) and Jovian Energetic Particle Detector Instrument (JEDI) to study Jupiter’s polar regions.

Ultraviolet auroral images of Jupiter from the Juno Ultraviolet Spectrograph instrument. Credit: NASA/SwRI/Randy Gladstone

As with Earth, on Jupiter, auroras are the result of intense radiation and Jupiter’s magnetic field. When this magnetosphere aligns with charged particles, it has the effect of accelerating electrons towards the atmosphere at high energy levels. In the course of examining Juno’s data, the JHUAPL team observed signatures of electrons being accelerated toward the Jovian atmosphere at energy levels of up to 400,000 electron volts.

This is roughly 10 to 30 times higher than what is experienced here on Earth, where only several thousand volts are typically needed to generate the most intense aurora. Given that Jupiter has the most powerful auroras in the Solar System, the team was not surprised to see such powerful forces at work within the planet’s atmosphere. What was surprising, however, was that this was not the source of the most intense auroras.

As Dr. Mauk, who leads the investigation team for the APL-built JEDI instrument and was the lead author on the study , explained in a JHUAPL press release:

“At Jupiter, the brightest auroras are caused by some kind of turbulent acceleration process that we do not understand very well. There are hints in our latest data indicating that as the power density of the auroral generation becomes stronger and stronger, the process becomes unstable and a new acceleration process takes over. But we’ll have to keep looking at the data.”

Image compiled using data from Juno’s Ultraviolet Spectrograph, which marks the path of Juno’s readings of Jupiter’s auroras. Credit: NASA/SwRI/Randy Gladstone

These findings could have significant implications for the study of Jupiter, who’s composition and atmospheric dynamics continue to be a source of mystery. It also has implications or the study of extra-solar gas giants and planetary systems. In recent decades, the study of these systems has revealed hundreds of gas giants that have ranged in size from being Neptune-like to many times the size of Jupiter (aka. “Super-Jupiters”).

These gas giants have also shown significant variations in orbit, ranging from being very close to their respective suns to very far (i.e. “Hot Jupiters” to “Cold Gas Giants”). By studying Jupiter’s ability to accelerate charged particles, astronomers will be able to make more educated guesses about space weather, radiation environments, and the risks they pose to space missions.

This will come in handy when it comes time to mount future missions to Jupiter, as well as deep-space and maybe even interstellar space. As Mauk explained:

“The highest energies that we are observing within Jupiter’s auroral regions are formidable. These energetic particles that create the auroras are part of the story in understanding Jupiter’s radiation belts, which pose such a challenge to Juno and to upcoming spacecraft missions to Jupiter under development. Engineering around the debilitating effects of radiation has always been a challenge to spacecraft engineers for missions at Earth and elsewhere in the solar system. What we learn here, and from spacecraft like NASA’s Van Allen Probes and MMS that are exploring Earth’s magnetosphere, will teach us a lot about space weather and protecting spacecraft and astronauts in harsh space environments. Comparing the processes at Jupiter and Earth is incredibly valuable in testing our ideas of how planetary physics works.”

Before the Juno mission is scheduled to wrap up (in February of 2018), the probe is likely to reveal a great many things about the planet’s composition, gravity field, magnetic field and polar magnetosphere. In so doing, it will address long-standing mysteries about how the planet formed and evolved, which will also shed light on the history of the Solar System and extra-solar systems.

Further Reading: JHUAPL, Nature

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Gravitational Waves will let us see Inside Stars as Supernovae Happen

Gravitational Waves will let us see Inside Stars as Supernovae Happen:

On February 11th, 2016, scientists at the Laser Interferometer Gravitational-wave Observatory (LIGO) announced the first detection of gravitational waves. This development, which confirmed a prediction made by Einstein’s Theory of General Relativity a century ago, has opened up new avenues of research for cosmologists and astrophysicists. Since that time, more detections have been made, all of which were said to be the result of black holes merging.

However, according to a team of astronomers from Glasgow and Arizona, astronomers need not limit themselves to detecting waves caused by massive gravitational mergers. According to a study they recently produced, the Advanced LIGO, GEO 600, and Virgo gravitational-wave detector network could also detect the gravitational waves created by supernova. In so doing, astronomers will able to see inside the hearts of collapsing stars for the first time.

The study, titled “Inferring the Core-Collapse Supernova Explosion Mechanism with Three-Dimensional Gravitational-Wave Simulations“, recently appeared online. Led by Jade Powell, who recently finished her PhD at the Institute for Gravitational Research at the University of Glasgow, the team argue that current gravitational wave experiments should be able to detect the waves created by Core Collapse Supernovae (CSNe).



Otherwise known as Type II supernovae, CCSNe are what happens when a massive star reaches the end of its lifespan and experiences rapid collapse. This triggers a massive explosion that blows off the outer layers of the star, leaving behind a remnant neutron star that may eventually become a black hole. In order for a star to undergo such collapse, it must be at least 8 times (but no more than 40 to 50 times) the mass of the Sun.

When these types of supernovae take place, it is believed that neutrinos produced in the core transfer gravitational energy released by core collapse to the cooler outer regions of the star. Dr. Powell and her colleagues believe that this gravitational energy could be detected using current and future instruments. As they explain in their study:

“Although no CCSNe have currently been detected by gravitational-wave detectors, previous studies indicate that an advanced detector network may be sensitive to these sources out to the Large Magellanic Cloud (LMC). A CCSN would be an ideal multi-messenger source for aLIGO and AdV, as neutrino and electromagnetic counterparts to the signal would be expected. The gravitational waves are emitted from deep inside the core of CCSNe, which may allow astrophysical parameters, such as the equation of state (EOS), to be measured from the reconstruction of the gravitational-wave signal.”

Dr. Powell and her also outline a procedure in their study that could be implemented using the Supernova model Evidence Extractor (SMEE). The team then conducted simulations using the latest three-dimensional models of gravitational-wave core collapse supernovae to determine if background noise could be eliminated and proper detection of CCSNe signals made.



As Dr. Powell explained to Universe Today via email:

“The Supernova Model Evidence Extractor (SMEE) is an algorithm that we use to determine how supernovae get the huge amount of energy they need to explode. It uses Bayesian statistics to distinguish between different possible explosion models. The first model we consider in the paper is that the explosion energy comes from the neutrinos emitted by the star. In the second model the explosion energy comes from rapid rotation and extremely strong magnetic fields.”

From this, the team concluded that in a three-detector network researchers could correctly determine the explosion mechanics for rapidly-rotating supernovae, depending on their distance. At a distance of 10 kiloparsecs (32,615 light-years) they would be able to detect signals of CCSNe with 100% accuracy, and signals at 2 kiloparsecs (6,523 light-years) with 95% accuracy.

In other words, if and when a supernova takes place in the local galaxy, the global network formed by the Advanced LIGO, Virgo and GEO 600 gravitational wave detectors would have an excellent chance of picking up on it. The detection of these signals would also allow for some groundbreaking science, enabling scientists to “see” inside of exploding stars for the first time. As Dr. Powell explained:

“The gravitational waves are emitted from deep inside the core of the star where no electromagnetic radiation can escape. This allows a gravitational wave detection to tell us information about the explosion mechanism that can not be determined with other methods. We may also be able to determine other parameters such as how rapidly the star is rotating.”

Illustration showing the merger of two black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. Credit: LIGO/T. Pyle

Dr. Powell, having recently completed work on her PhD will also be taking up a postdoc position with the RC Centre of Excellence for Gravitational Wave Discovery (OzGrav), the gravitational wave program hosted by the University of Swinburne in Australia. In the meantime, she and her colleagues will be conducting targeted searchers for supernovae that occurred during the first and seconds advanced detector observing runs.

While there are no guarantees at this point that they will find the sought-after signals that would demonstrate that supernovae are detectable, the team has high hopes. And given the possibilities that this research holds for astrophysics and astronomy, they are hardly alone!

Further Reading: arXiv

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Unexpected Solar Flare is Also the Largest in Twelve Years

Unexpected Solar Flare is Also the Largest in Twelve Years:

The past summer has been a pretty terrible time in terms of weather. In addition to raging fires in Canada’s western province of British Columbia, the south-eastern United States has been pounded by successive storms and hurricanes – i.e. Tropical Storm Emily and Hurricanes Franklin, Gert, Harvey and Irma. As if that wasn’t enough, solar activity has also been picking up lately, which could have a serious impact on space weather.

This past week, researchers from the University of Sheffield in the UK and Queen’s University Belfast detected the largest solar flare in 12 years. This massive burst of radiation took place on Wednesday, September 6th, and was one of three observed over a 48-hour period. While this latest solar flare is harmless to humans, it could pose a significant hazard to communications and GPS satellites.

The flare was also the eighth-largest detected since solar flare activity began to be monitored back in 1996. Like the two previous flares which took place during the same 48-hour period, this latest burst was an X-Class flare – the largest type of flare known to scientists. It occurred at 13:00 GMT (06:00 PDT; 09:00 EST) and was measured to have an energy level of X9.3.



Essentially, it erupted with the force of one billion thermonuclear bombs and drove plasma away from the surface at speeds of up to 2000 km/s (1243 mi/s). This phenomena, known as Coronal Mass Ejections (CMEs), are known to play havoc with electronics in Low Earth Orbit (LEO). And while Earth’s magnetosphere offers protection from these events, electronic systems on the planets surface are sometimes affected as well.

The event was witnessed by a team from a consortium of Universities, which included the University of Sheffield and Queen’s University Belfast. With the support of the Science and Technology Facilities Council, they conducted their observations using the Institute for Solar Physics‘ (ISP) 1-meter Swedish Solar Telescope, which is located at the Roque de los Muchachos Observatory – operated by the Instituto de Astrofisica de Canarias.

As Professor Mihalis Mathioudakis, who led the project at Queen’s University Belfast, indicated in a recent University of Sheffield press statement:

“Solar flares are the most energetic events in our solar system and can have a major impact on earth. The dedication and perseverance of our early career scientists who planned and executed these observations led to the capture of this unique event and have helped to advance our knowledge in this area.”

The team was able to capture the opening moments of a solar flare’s life. This was extremely fortunate, since one of the biggest challenges of observing solar flares from ground-based telescopes is the short time-scales over which they erupt and evolve. In the case of X-class flares, they are capable of forming and reaching peak intensity in just about five minutes.

A powerful X2-class flare from sunspot region 2297 glows fiery yellow in this photo taken by NASA’s Solar Dynamics Observatory on March 11, 2015. Credit: NASA

In other words, observers – who only see a small part of the sun at any one moment – must act very quickly to ensure they catch the crucial opening moments of a flare’s evolution. As Dr Chris Nelson, from the Solar Physics and Space Plasma Research Centre (SP2RC) – who was one of the observers at the telescope – explained:

“It’s very unusual to observe the opening minutes of a flare’s life. We can only observe about 1/250th of the solar surface at any one time using the Swedish Solar Telescope, so to be in the right place at the right time requires a lot of luck. To observe the rise phases of three X-classes over two days is just unheard of.”

Another interesting thing about this flare, and the two that preceded it, was the timing. At present, astronomers expected that we were in a period of diminished solar activity. But as Dr Aaron Reid, a research fellow at at Queen’s University Belfast’s Astrophysics Research Center and a co-author on the paper, explained:

“The Sun is currently in what we call solar minimum. The number of Active Regions, where flares occur, is low, so to have X-class flares so close together is very usual. These observations can tell us how and why these flares formed so we can better predict them in the future.”

Professor Robertus von Fáy-Siebenbürgen, who leads the SP2RC, was also very enthused about the research team’s accomplishment. “We at SP2RC are very proud to have such talented scientists who can make true discoveries,” he said. “These observations are very difficult and will require hard work to fully understand what exactly has happened on the Sun.”



Predicting when and how solar flares will occur will also aid in the development of early warning and preventative measures. The is part of growing industry that seeks to protect satellites and orbital missions from harmful electromagnetic disruption. And with humanity’s presence in LEO expended to grow considerably in the coming decades, this industry is expected to become worth several billion dollars.

Yes, with everything from small satellites, space planes, commercial habitats and more space stations being deployed to space, Low Earth Orbit is expected to get pretty crowded in the coming decades. The last thing we need is for vast swaths of this machinery or – heaven forbid! – crewed spacecraft, stations and habitats to become inoperative thanks to solar flare activity.

If human beings are to truly become a space-faring race, we need to know how to predict space weather the same we do the weather here on Earth. And just like the wind, the rain, and other meteorological phenomena, we need to know when to batten down the hatches and adjust the sails.

Further Reading: University of Sheffield

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Hubble spots exoplanet with glowing water atmosphere

Hubble spots exoplanet with glowing water atmosphere:

This artist’s concept shows hot Jupiter WASP-121b, which presents the best evidence yet of a stratosphere on an exoplanet. Image & Caption Credit: Engine House VFX, At-Bristol Science Centre, University of Exeter

Researchers working with data from NASA’s Hubble Space Telescope have found the strongest evidence to date for the existence of a stratosphere – the layer of an atmosphere in which temperature increases with altitude – on an exoplanet (a planet outside of the Solar System). The new study was published in the August 3, 2017, issue of the journal Nature.

“This result is exciting because it shows that a common trait of most of the atmospheres in our solar system – a warm stratosphere – also can be found in exoplanet atmospheres,” said Mark Marley, the study’s co-author who is based at NASA’s Ames Research Center. “We can now compare processes in exoplanet atmospheres with the same processes that happen under different sets of conditions in our own solar system.”

The researchers studied WASP-121b, an example of a type of exoplanet called a “hot Jupiter”. The planet’s mass is 1.2 times the that of Jupiter and its radius is 1.9 times Jupiter’s. Wasp-121b is much closer to its star than Jupiter is to the Sun. While it takes Jupiter 12 years to revolve once around the Sun, WASP-121 orbits its star once every three days. If the exoplanet were any closer to its star, the star’s gravity would rip it apart. WASP-121’s atmosphere is heated to 4,600 degrees Fahrenheit (2,500 degrees Celsius), hot enough to boil some metals.

An earlier study found possible signs of a stratosphere on the exoplanet WASP-33b and other hot Jupiters. The new study provides the strongest evidence yet because scientist observed the signature of hot water molecules for the first time.

“Theoretical models have suggested stratospheres may define a distinct class of ultra-hot planets, with important implications for their atmospheric physics and chemistry,” said Tom Evans, lead author and research fellow at the University of Exeter, United Kingdom. “Our observations support this picture.”

The scientists studied the atmosphere of WASP-121 by using Hubble’s spectroscopy capabilities to analyze how different molecules react to specific wavelengths of light. For example, water vapor in the planet’s atmosphere behaves in predictable ways depending on the temperature of the water.

The top of the planet’s atmosphere is heated to a blazing 4,600 degrees Fahrenheit (2,500 Celsius), hot enough to boil some metals. Image & Caption Credit: NASA, ESA, and G. Bacon (STSci)

A star’s light can penetrate deep into a planet’s atmosphere, raising the temperature of the gas there. The gas then radiates its heat into space as infrared light. If there is cooler water vapor at the top of the atmosphere, the water molecules will block certain wavelengths of light from escaping into space. If, however, the water molecules at the top of the atmosphere have a higher temperature, they will glow at the same wavelengths.

“The emission of light from water means the temperature is increasing with height,” said Tiffany Kataria, the study’s co-author based at NASA’s Jet Propulsion Laboratory, Pasadena, California. “We’re excited to explore at what longitudes this behavior persists with upcoming Hubble observations.”

In Earth’s stratosphere, ozone gas traps ultraviolet radiation from the Sun, raising the temperature of this layer of the atmosphere. Other bodies within the Solar System also have a stratosphere. For example, methane is responsible for heating the stratospheres of Jupiter as well as Saturn’s moon Titan.

In planets of the Solar System, the change in temperature within a planet’s stratosphere is approximately 100 degrees Fahrenheit (about 56 degrees Celsius). On WASP-121b, the temperature in the stratosphere rises by 1,000 degrees Fahrenheit (560 degrees Celsius). Researchers do not yet know which chemicals are responsible for the temperature in WASP-121b’s atmosphere. Vanadium oxide and titanium oxide are possible candidates because they are commonly found in brown dwarfs – “failed stars” that share some characteristics with exoplanets. Compounds such as these are expected to be found on only the hottest of hot Jupiters because high temperatures are required to keep them in a gaseous state.

“This super-hot exoplanet is going to be a benchmark for our atmospheric models, and it will be a great observational target moving into the Webb era,” said Hannah Wakeford, the study’s co-author who worked on this research while at NASA’s Goddard Space Flight Center, Greenbelt, Maryland.

Video courtesy of NASA

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