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

The post Unexpected Solar Flare is Also the Largest in Twelve Years appeared first on Universe Today.

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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Large, distant comets more common than previously thought

Large, distant comets more common than previously thought:

An artist’s rendering of the NASA’s WISE mission, renamed NEOWISE in 2013, observing comets and other deep space objects. Image Credit: NASA

Data from NASA’s Wide-field Infrared Survey Explorer (WISE) mission has shown that large, distant comets are more common than previously thought. This is according to research published in the Astronomical Journal. These “long-period” comets originate from the distant Oort Cloud, and the information provided by the NASA’s spacecraft is contributing to a better understanding of how common these icy worldlets might be.

While most people are likely familiar with icy objects such famous comets as Halley and Shoemaker-Levy 9, the latter of which broke up and impacted the gas giant Jupiter in July 1994. These, along with nearly all of those most of us have heard about (or seen) are from the family of “short-period” comets. Short-period refers to the length and distance of the period, or the time it takes to make one full orbit, of the object.

Short-period comets take less than 200 years to make a full orbit around the Sun. These are generally separated into two families: Jupiter family and inclined-period comets. Jupiter family comets, of which Shoemaker-Levy 9 was one, have orbital periods of less than 20 years. Inclined-period comets, like Halley’s Comet, have orbital periods between 20 and 200 years in length.

This illustration shows how scientists used data from NASA’s WISE spacecraft to determine the nucleus sizes of comets. They subtracted a model of how dust and gas behave in comets in order to obtain the core size. Image and Caption Credit: NASA / JPL-Caltech

A short-period comet tends to orbit within the ecliptic – the plane of space where the planets orbit around the Sun. This is likely due to where they originate from, which is suspected to be the Kuiper Belt – the icy band of objects at the edge of the Solar System where Pluto, the majority of dwarf planets, and about a thousand other Kuiper Belt Objects (KBOs) roam. The Kuiper Belt exists at a distance of some 2.7 billion to 5.1 billion miles (4.4 billion to 8.2 billion kilometers).

Unlike short-period comets, long-period comets originate from much further away in the Oort Cloud, an area of the Solar System believed to be a vast a spherical bubble of icy material thought to extend approximately 186 billion miles (300 billion kilometers) out to as far as 4.45 trillion miles (7.5 trillion kilometers). Objects originating from this area have periods greater than 200 years, with some taking thousand or even millions of years to make a single orbit.

In the paper published about long-period comets, researchers looked at data from the WISE mission that did a full sky survey from 2009 to 2011. Data from an eight-month span of time was reviewed and a total of 95 Jupiter family comets along with 56 long-period comets were identified.

“Our study is a rare look at objects perturbed out of the Oort Cloud,” said Amy Mainzer, study co-author based at NASA’s Jet Propulsion Laboratory in Pasadena, California, and principal investigator of the NEOWISE mission. “They are the most pristine examples of what the Solar System was like when it formed.”

The study also found that there were seven times more long-period comets measuring at least 0.6 miles (1.0 kilometer) across than previously predicted, with the average width measuring 1.3 miles (2.1 kilometers), about twice as large as the average diameter of Jupiter family and inclined-period comets. Additionally, over that eight month period, the number of long-period comets that passed by the Sun was 3‒5 times more than previously anticipated.

The suspected reasons for the differences in the size between Jupiter family comets and long-period comets are believed to be due to two main possibilities; the first being that because Jupiter family comets make far more frequent trips nearer to the Sun, they are subjected to more sublimation (ice changing directly to a gas) and thus loss of total mass.

Another possible cause for the size difference is due to evolutionary differences. Because the Oort Cloud is so large, and the objects within it are so widely distributed, the likelihood of objects impacting one another is reduced, giving bodies in this area a better chance of keeping their large sizes rather than suffering impacts that could break them down.

When scientists reviewed the movement of these bodies, they found that there was an inclination (the angle to the ecliptic plane that the planets are aligned on) clustering at 110 degrees with an average perihelion (closest approach to the Sun in its elliptical orbit) of 2.9 astronomical units (270 million miles / 434 million kilometers), putting their closest approach to the Sun at just past the orbit of the dwarf planet Ceres in the main asteroid belt. This could indicate that there were larger bodies that broke up over time leaving behind these icy objects.

As if being big and coming at us from all different angles wasn’t bad enough, comets are fast – really fast.

“Comets travel much faster than asteroids, and some of them are very big,” Mainzer said. “Studies like this will help us define what kind of hazard long-period comets may pose.”

NASA’s Jet Propulsion Laboratory managed and operated WISE for NASA’s Science Mission Directorate located in Washington. The NEOWISE project is funded by the Near Earth Object Observation Program, now part of NASA’s Planetary Defense Coordination Office. The spacecraft was put into hibernation mode in 2011 after twice scanned the entire sky, thereby completing its main objectives. In September 2013, WISE was reactivated, renamed NEOWISE and assigned a new mission to assist NASA’s efforts to identify potentially hazardous near-Earth objects.

Video courtesy of NASA / Jet Propulsion Laboratory

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‘Great American Eclipse’ offers opportunity for millions

‘Great American Eclipse’ offers opportunity for millions:

On Aug. 21, 2017, the entire continental U.S. will see a solar eclipse. Only a 70-mile wide stripe across the central part of the country will experience totality. Image Credit: NASA

It’s not often an entire country has the opportunity to be an active part of something historic, but on Monday, August 21, 2017, anyone in the United States, most of Canada, some parts of Mexico, and some countries in the Caribbean will be able to do just that. This will mark the first time in nearly a century that a total solar eclipse will pass across the entirety of the U.S. from the Pacific to the Atlantic, and the next time this will happen won’t be until 2045.

Eclipses have been a part of the history of every culture since the beginning of humanity. Ancient societies as far back as 1375 B.C. have recorded total solar eclipses. Most believed that eclipses, both solar and lunar, were portents of events to come. The majority saw eclipses as fearful events – things that went against the laws of nature and their gods.

A total solar eclipse. Photo Credit: NASA

The alignment of celestial bodies is an astronomical event called syzygy. This can create an eclipse, occultation, or transit. As much as the average citizen looks forward to the wonder and beauty of an eclipse, scientists around the world use syzygy to do some remarkable science.

Some of the most pivotal discoveries in modern memory have been due to syzygy. These include Sir Arthur Eddington’s proof of Einstein’s Theory of Relativity by the observation of the Sun’s gravity bending the spacetime around it to reveal the light of a star hidden behind the Sun during an eclipse, and the discovery of thousands of extra-solar planets (exoplanets) by the Kepler Space Telescope using the transit method or even by ground-based telescopes using microlensing.

For instance, the scientists behind the New Horizons mission that visited Pluto in 2015 have recently used stellar occultation to gather more information on the small Kuiper belt object known as 2014 MU₆₉ prior to the spacecraft’s flyby of it coming up in January 2019.

Astronomers and other scientists use these events to gather information that can’t be gathered in any other way. Total solar eclipses provide an opportunity to view a part of the Sun we cannot properly see any other way – the corona.

The corona is the outermost layer of the Sun and is equivalent to its atmosphere. It is one of the most mysterious aspects of our closest star. NASA recently renamed Parker Solar Probe will be launched next year to study this mysterious part of the Sun.

Unlike every other place we are aware of, the farther you get from the center of a planet or other celestial body, the cooler the temperatures get. That’s not how it is with the corona of the Sun. In fact, the corona of the Sun is millions of degrees hotter than the surface of the Sun.

Capturing the moment

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For many astrophotographers, capturing a total solar eclipse is one of their bucket list items. It’s not a simple photograph to be able to capture for myriad reasons, the smallest of which is trying to be in the right place at just the right time. Even if you find the right spot along the line of totality, there’s no guarantee the weather will cooperate. Additionally, totality will only last for a maximum of 2 minutes, 40 seconds, depending on where you are. Click here for a list of totality times.

As many eclipse chasers can attest, you can spend large sums of money traveling to remote locales only to find that clouds block the view. Because the surface of the Earth is covered primarily in oceans, the likelihood of an eclipse happening on inhabited land is pretty low, which is what makes the August 21 eclipse a truly special event.

The path of totality for the Aug. 21, 2017, total solar eclipse. Image Credit: NASA

This eclipse has been billed by some as the “Great American Eclipse” since the entire path of totality occurs only touches land within the borders of the United States and has the potential to be the most-viewed eclipse ever.

Massive numbers of people from all over the planet are making the trek to locations along the path of totality in order to see this celestial event. Most of the areas where the eclipse will be viewable in totality happen to be relatively small towns and rural areas, some of which are expecting massive influxes of people.

Madras, Oregon, for example, normally has a population of approximately 6,000 people. That is expected to swell to over 100,000 for the days before and on the day of the eclipse. This poses a list of potential infrastructure problems including gas shortages, nightmare-level traffic jams, and price gouging on anything and everything.

Even so, people seem happy and excited to have even a chance to see the eclipse. Liam Kennedy, owner and inventor of ISS-Above, drove two days from Southern California to central Oregon to view the eclipse and is looking forward to “being enveloped in the Moon’s shadow”.

“I mean, literally, there will be a shadow on me from the Moon,” Kennedy said. “There will be a direct connection between me, and the Moon and the Sun! I mean, wow!”

This excitement and interest span a wide range of ages and genders. From school-age children to long-retired people who have never had the opportunity to see an eclipse before, the fevered interest is palpable.

Astrophotography hobbyist and amateur astronomer Chris Hetlage plans to stay mobile and try to outsmart Mother Nature. Hetlage, who began taking photographs in the late 1980s, has out run weather in order to get stunning images of lunar eclipses and even the transit of Venus. After capturing an annular eclipse in Chico, California, in 2012, he knew he wanted to photograph a total eclipse.

Hetlage plans to be well armed with a plethora of equipment in order to maximize the possibility of imaging the eclipse somewhere between Saint Louis and Kansas City in Missouri, and he will go as far as Nebraska or Montana depending on how the weather looks leading up to the eclipse.

The crew of the International Space Station witnessed the shadow of the Moon racing across Earth during the March 29, 2006, total solar eclipse. Photo Credit: NASA

Citizen science opportunities

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Once the eclipse starts, if you’re not in the path, it’s virtually impossible to chase it. The shadow of the Moon moves at speeds upward of 2,288 mph (3,683 km/h), which is greater than the speed of sound. People have stood on mountain tops and watched the Moon’s shadow race across hundreds of miles to find them in just a matter of minutes.

For those who aren’t familiar with the affects of a solar eclipse, the changes in temperature, development of clouds, shifts in winds, and even animal activity can be startling. For those who aren’t in the path of totality, there can still be significant impacts.

NASA sponsors an application called the Globe Observer that they hope will appeal to citizen scientists. The application gathers data about weather, temperature, with other projects about animal behavior, coronal imaging, and ionosphere activity from across a wide range of areas where both totality and partial eclipse will be able to be seen. The data is then correlated by scientists in an attempt to better understand the impacts of the Sun on the weather here on Earth.

Those interested in conducting eclipse related citizen science can download the Globe Observer application as well as the many other ways to personally participate in citizen science projects.

For those who aren’t among the millions of people expected to be within the path of totality, or are but the weather in your area isn’t cooperating, NASA TV will be live-streaming the event from special high-elevation balloons, ground-based telescopes using various types of light and polarization filters, and even from specially outfitted jets.

Partial eclipse viewing safety

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Even if one isn’t in the path of totality but will be within the continental U.S., the whole continent will still be able to see a partial solar eclipse. The most crucial aspect to viewing this phase is taking precautions for viewing safety.

Just like when the skin gets a sunburn, it’s not an immediate discomfort. When the inside of the eye receives a sunburn from exposure to the damaging rays of the Sun, it’s especially problematic because the inside of the eye doesn’t possess pain receptors. This means that the damage can go unnoticed until the delicate tissues of the retina become swollen and inflamed reducing vision. This can reverse over time, but in some cases vision can be permanently lost.

Only view the eclipse with approved eclipse safety glasses or viewers, or, better yet, make a pinhole projector to indirectly observe the eclipse. Indirect observation guarantees you won’t damage your vision. Pinhole projectors are easy to create and very inexpensive, taking from five to 10 minutes for the pinhole projector.

If you’re unable to make it to the path of totality or are unable to fully appreciate it from your location, you can start planning now for the next total solar eclipse that will be in the United States on April 8, 2024.

Video courtesy of NASA

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Saturn Moon Tethys Shines Above Rings in Gorgeous Photo

Saturn Moon Tethys Shines Above Rings in Gorgeous Photo:

The icy moon Tethys sits above Saturn's rings in this photo captured on May 13, 2017, by NASA's Cassini spacecraft.

Credit: NASA/JPL-Caltech/Space Science Institute

Saturn's icy moon Tethys hovers above the planet's iconic rings in a breathtaking photo by NASA's Cassini spacecraft.

Though NASA released the image Monday (Aug. 21), Cassini actually captured it on May 13, 2017. At the time, the probe was about 750,000 miles (1.2 million kilometers) from Saturn and 930,000 miles (1.5 million km) from Tethys, agency officials said.

The night side of Tethys is lit up by "Saturnshine" — sunlight reflected off its parent planet — in the image. But this Saturnshine isn't quite as powerful as the photo makes it seem.

"Tethys was brightened by a factor of two in this image to increase its visibility," NASA officials wrote in an image description. "A sliver of the moon's sunlit northern hemisphere is seen at top. A bright wedge of Saturn's sunlit side is seen at lower left."

At 660 miles (1,062 km) across, Tethys is the fifth-largest moon of Saturn. (The only bigger ones are Titan, Rhea, Iapetus and Dione.) Tethys has some pretty dramatic features that aren't visible in this photo — a deep canyon that snakes across three-fourths of its surface, for example, and a crater called Odysseus that's 250 miles (400 km) wide.

Cassini has been capturing stunning images like this one since arriving in orbit around Saturn in July 2004. But the probe's work is nearly done: Cassini is in the "Grand Finale" phase of its mission, which will culminate with an intentional death dive into Saturn's thick atmosphere on Sept. 15.

This maneuver is designed to ensure that Cassini doesn't contaminate Titan or fellow Saturn satellite Enceladus with microbes from Earth. (Astrobiologists think Titan and Enceladus may be capable of supporting life.)

The $3.2 billion Cassini-Huygens mission is a collaboration involving NASA, the European Space Agency and the Italian Space Agency. Huygens was a piggyback lander that traveled with the Cassini mothership and touched down on Titan in January 2005.

Follow Mike Wall on Twitter @michaeldwall and Google+. Follow us @Spacedotcom, Facebook or Google+. Originally published on Space.com.