New Horizons’ KBO target may be a binary

New Horizons’ KBO target may be a binary:

Artist’s impression of NASA’s New Horizons spacecraft, en route to a January 2019 encounter with Kuiper Belt Object 2014 MU₆₉. Image & Caption Credit: NASA / JHU-APL / SwRI

New Horizons’ second target – Kuiper Belt Object (KBO) 2014 MU₆₉ – may actually be a binary system composed of two objects that either touch one another or orbit very close together, according to observations conducted by mission scientists when the KBO passed in front of a star on July 17, 2017.

Members of the New Horizons team observed the occultation by deploying a network of telescopes along the path of MU69’s shadow in a remote part of Argentina.

Their goal was to capture its shadow, thereby obtaining data about the KBO’s size, shape, orbit, and environment as well as information that will enable accurate refining of the spacecraft’s trajectory.

MU69 is the second target of NASA’s New Horizons spacecraft and part of its approved extended mission by the space agency. It will be the most distant object ever visited by a spacecraft.

The probe famously flew by the Pluto system on July 14, 2015, obtaining a plethora of images and data about the binary Pluto-Charon and their four small moons.

The July 17, 2017, occultation was the third of three such events this year, all of which were carefully observed by mission scientists after they used both the Hubble Space Telescope and the European Space Agency’s (ESA) Gaia satellite to pinpoint exactly where MU69’s shadow would fall on Earth each time.

Based on data collected during the first occultation in June, mission scientists raised the possibility that MU69, located a billion miles (1.6 billion kilometers) beyond Pluto and more than four billion miles (6.5 billion kilometers) from Earth, might actually be a swarm of many small objects rather than a single object.

However, observations conducted during the third occultation indicate the object is either two objects closely orbiting each other, a contact binary in which the two objects actually touch one another, or a single, strangely shaped object missing a large chunk of material.

Mission scientists think it or both objects may be shaped like a “skinny football” – a shape formally described as an “extreme prolate spheroid”.

LEFT: An artist’s concept of Kuiper Belt Object 2014 MU69, the next flyby target for NASA’s New Horizons mission. This binary concept is based on telescope observations made at Patagonia, Argentina, on July 17, 2017, when MU69 passed in front of a star. New Horizons scientists theorize that it could be a single body with a large chunk taken out of it, or two bodies that are close together or even touching. RIGHT: Another artist’s concept of Kuiper Belt Object 2014 MU69, which is the next flyby target for NASA’s New Horizons mission. Scientists speculate that the Kuiper Belt object could be a single body with a large chunk taken out of it, or two bodies that are close together or even touching. Images & Captions Credit: NASA / JHU-APL / SwRI / Alex Parker

Two of Pluto’s small moons, Kerberos and Hydra, as well as Comet 67P/Churyumov–Gerasimenko, are single objects composed of two lobes.

“This new finding is simply spectacular. The shape of MU69 is truly provocative, and could mean another first for New Horizons going to a binary object in the Kuiper Belt,” said mission Principal Investigator Alan Stern of the Southwest Research Institute (SwRI) in Boulder, Colorado. “I could not be happier with the occultation results, which promise a scientific bonanza for the flyby.”

New Horizons will fly by MU69 on January 1, 2019.

From observations of the third occultation, scientists now have a better handle on MU69’s size, which they estimate to be no longer than 20 miles (30 kilometers) if the KBO is a single object.

If MU69 is a binary composed of two objects, each one is estimated to have a diameter of nine to twelve miles (15–20 kilometers).

Stern credited the successes of the occultation observations to the Hubble Space Telescope and Gaia Observatory, which provided crucial information about the path of MU69’s shadow on Earth on all three occasions.

Occultation data and images are available on New Horizons’ KBO Chasers site.



The post New Horizons’ KBO target may be a binary appeared first on SpaceFlight Insider.

Revealed: What the Sun's Outer Atmosphere Will Look Like During the Total Solar Eclipse

Revealed: What the Sun's Outer Atmosphere Will Look Like During the Total Solar Eclipse:

Researchers from the National Solar Observatory Integrated Synoptic Program predict the structure of the solar corona for the Aug. 21, 2017, total solar eclipse. The field lines of a solar coronal magnetic model shown in the image are based on measurements taken one solar rotation, or 27.2753 Earth days, before the total solar eclipse

Credit: NSO/NSF

With the Aug. 21 total solar eclipse only a few weeks away, astronomers have revealed what the sun's outer atmosphere is likely to look like as the sun disappears behind the moon.

The Aug. 21 eclipse will sweep across the continental U.S. from Oregon to South Carolina along a stretch of land about 70 miles (113 kilometers) wide. Skywatchers within this path will experience totality, when the moon appears to move directly in front of the solar disk and casts a long shadow on Earth. Viewers outside of the path of totality will still experience a partial solar eclipse.

During a total solar eclipse, skywatchers have the opportunity to see the sun's glowing outer atmosphere, known as the corona. The jets and streamers present in the corona become visible because the moon blots out much of the bright light of the sun's disk, which typically overwhelms the light from the corona. [How to Safely Watch the 2017 Total Solar Eclipse]

The corona is more than a glowing halo of light. It is incredibly hot — it can reach temperatures of 3.5 million degrees Kelvin (3.49 million degrees Celsius or 6.29 million degrees Fahrenheit) — and has an intricate structure created by the sun's magnetic-field lines.

Using measurements from the National Solar Observatory Integrated Synoptic Program (NSO/NISP), astronomers were able to model the shape of the solar coronal magnetic field as of July 25, which represents one solar rotation, or 27.2753 Earth days, before the Aug. 21 total solar eclipse.

"Since we are exactly one solar rotation away from the solar eclipse, we're able to use today's observations to predict the structure of the corona on Aug. 21st," Gordon Petrie, an astronomer from the NSO, said in a statement. "The corona is not likely to change too much between now and the eclipse, unless we get lucky and a large active region appears!"

"We expect to see faint, straight structures protruding from the north and south poles of the sun — these are the polar plumes," Petrie added. "We will be able to see brighter bulbs of material closer to the equator — these are called helmet streamers."

Electric currents inside the sun generate a magnetic field that changes over time, depending on where the sun is in its 11-year activity cycle. Astronomers are able to trace the magnetic fields of the corona by observing the superheated gases present in the sun's atmosphere. Astronomers compare this technique to "the middle-school experiment where you sprinkle iron filings over a bar magnet to get a butterfly shape," according to the statement.

"The corona changes its shape over time, and looks drastically different during solar maximum compared to solar minimum," David Boboltz, the National Science Foundation's program officer for the NSO, said in the statement. "During solar maximum, such as the 2012 eclipse, the corona looks like a spiky ring around the entire sun. In contrast, a solar minimum eclipse such as the one this month, will have lots of complexity near the equator but will be drastically different near the north and south poles of the sun."

While skywatchers in the path of totality will experience no more than 2 minutes and 40 seconds of darkness in any one location, scientists will be able to combine observations taken of the sun's corona over the course of 90 minutes — the time it takes the moon's dark shadow to travel from the West Coast to the East Coast. This will allow astronomers to further study the corona and its structure.

What's more, the NSO is also helping to build the Daniel K. Inouye Solar Telescope (DKIST) on the Hawaiian island of Maui, which will allow scientists to measure the magnetic fields in the solar corona directly for the first time, according to the statement.

"The solar corona is largely an enigma," Valentin Pillet, director of the NSO, said in the statement. "For now, the best we can do is compare high resolution images of the solar corona, such as those we'll obtain during the eclipse, to our theoretical models. But DKIST will allow us to actually measure the magnetic fields in the corona. This will be revolutionary in the field of solar physics."

Follow Samantha Mathewson @Sam_Ashley13. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

China's Tiangong-1 Space Lab to Fall to Earth by April 2018

China's Tiangong-1 Space Lab to Fall to Earth by April 2018:

Artist's illustration of China's 8-ton Tiangong-1 space lab, which is expected to fall to Earth late next year, unless it's boosted to a higher altitude.

Credit: CMSE

The United Nations Office for Outer Space Affairs (UNOOSA) has reissued a notification by China on the future uncontrolled re-entry of the country's robotic Tiangong-1 space lab, which is expected to take place in the next eight months.

Tiangong-1, which has been orbiting Earth since September 2011, ceased functioning on March 16, 2016. To date, the spacecraft has maintained its structural integrity.

The space lab's operational orbit is under constant and close surveillance by China. Its current average altitude is 217 miles (349 kilometers), but its orbit is decaying at a daily rate of approximately 525 feet (160 meters), according to the notification. [Gallery: Tiangong 1, China's First Space Laboratory]

Re-entry date

The lab's re-entry is expected between October 2017 and April 2018. According to the calculations and analysis that have been carried out, most of Tiangong-1's structural components will be burned up during the craft's re-entry into Earth's atmosphere.

"The probability of endangering and causing damage to aviation and ground activities is very low," the notification adds.

Taking measures

The notice advises that China attaches great importance to the re-entry of Tiangong-1 and will take the following measures to monitor its fall and provid public information:

— China will enhance monitoring and forecasting and make strict arrangements to track and closely keep an eye on Tiangong-1 and will publish a timely forecast of its re-entry

— China will make use of the international joint monitoring information under the framework of the Inter-Agency Space Debris Coordination Committee in order to be better informed about the descent of Tiangong-1.

— China will improve the information reporting mechanism. Dynamic orbital status and other information relating to Tiangong-1 will be posted on the website of the China Manned Space Agency in both Chinese and English. In addition, timely information about important milestones and events during the orbital decay phases will be released through the news media.

— As to the final forecast of the time and region of re-entry, China will issue the relevant information and early warning in a timely manner and bring it to the attention of the United Nations Office for Outer Space Affairs and the Secretary-General of the United Nations through diplomatic channels.

Altitude history of China’s Tiangong-1 space lab.

Credit: The Aerospace Corporation’s Center for Orbital and Reentry Debris Studies (CORDS)

Possible leftovers

Tiangong-1 was launched into Earth orbit on September 29, 2011. It conducted six successive rendezvous and dockings with the spacecraft Shenzhou-8 (uncrewed), Shenzhou-9 (crewed) and Shenzhou-10 (crewed) as part of China's human space exploration activities. The vehicle weighed 18,740 lbs. (8,500 kilograms) at launch.

According to the Aerospace Corporation, based on Tiangong-1's inclination, the lab will re-enter somewhere between 43 degrees north and 43 degrees south latitudes. As for leftovers, "it is highly unlikely that debris from this reentry will strike any person or significantly damage any property," Aerospace Corporation representatives wrote in a Tiangong-1 re-entry FAQ.

They added: "Potentially, there may be a highly toxic and corrosive substance called hydrazine on board the spacecraft that could survive re-entry. For your safety, do not touch any debris you may find on the ground nor inhale vapors it may emit."

The Aerospace Corporation will perform a person and property risk calculation for the Tiangong-1 re-entry a few weeks prior to the event.  

Leonard David is author of "Mars: Our Future on the Red Planet," published by National Geographic. The book is a companion to the National Geographic Channel series "Mars." A longtime writer for Space.com, David has been reporting on the space industry for more than five decades. Follow us @Spacedotcom, Facebook or Google+. This version of this story was posted on Space.com.

NASA Voyager Probes Still Going Strong After 40 Years

NASA Voyager Probes Still Going Strong After 40 Years:



Forty years ago, the Voyager 1 and 2 missions began their journey from Earth to become the farthest-reaching missions in history. In the course of their missions, the two probes spent the next two decades sailing past the gas giants of Jupiter and Saturn. And while Voyager 1 then ventured into the outer Solar System, Voyager 2 swung by Uranus and Neptune, becoming the first and only probe in history to explore these worlds.

This summer, the probes will be marking the fortieth anniversary of their launch – on September 5th and August 20th, respectively. Despite having traveled for so long and reaching such considerable distances from Earth, the probes are still in contact with NASA and sending back valuable data. So in addition to being the most distant missions from Earth, they are the longest-running mission in history.

In addition to their distance and longevity, the Voyager spacecraft have also set numerous other records for robotic space missions. For example, in 2012, the Voyager 1 probe became the first and only spacecraft to have entered interstellar space. Voyage 2, meanwhile, is the only probe that has explored all four of the Solar System’s gas/ice giants – Jupiter, Saturn, Uranus and Neptune.

The launch of the Voyager 2 probe, which took place on August 20th, 1977. Credit: NASA

Their discoveries also include the first active volcanoes beyond Earth – on Jupiter’s moon Io – the first evidence of a possible subsurface ocean on Europa, the dense atmosphere around Titan (the only body beyond Earth with a dense, nitrogen-rich atmosphere), the craggy surface of Uranus’ “Frankenstein Moon” Miranda, and the ice plume geysers of Neptune’s largest moon, Triton.

These accomplishments have had immeasurable benefits for planetary science, astronomy and space exploration. They’ve also paved the way for future missions, such as the Galileo and Juno probes, the Cassini-Huygens mission, and the New Horizons spacecraft. As Thomas Zurbuchen, the associate administrator for NASA’s Science Mission Directorate (SMD), said in a recent press statement:

“I believe that few missions can ever match the achievements of the Voyager spacecraft during their four decades of exploration. They have educated us to the unknown wonders of the universe and truly inspired humanity to continue to explore our solar system and beyond.”

But what is perhaps most memorable about the Voyager missions is the special cargo they carry. Each spacecraft carries what is known as the Golden Record, a collection of sounds, pictures and messages that tell of Earth, human history and culture. These records were intended to serve as a sort of time capsule and/or message to any civilizations that retrieved them, should they ever be recovered.

Each of the two Voyager spacecraft launched in 1977 carry a 12-inch gold-plated phonograph record with images and sounds from Earth. Credit: NASA

As noted, both ships are still in contact with NASA and sending back mission data. The Voyager 1 probe, as of the writing of this article, is about 20.9 billion km (13 billion mi; 140 AU) from Earth. As it travels northward out of the plane of the planets and into interstellar space, the probe continues to send back information about cosmic rays – which are about four times as abundant in interstellar space than around Earth.

From this, researchers have learned that the heliosphere – the region that contains the Solar System’s planets and solar wind – acts as a sort of radiation shield. Much in the say that Earth’s magnetic field protects us from solar wind (which would otherwise strip away our atmosphere), the heliopause protects the Solar planets from atomic nuclei that travel at close to the speed of light.

Voyager 2, meanwhile, is currently about 17.7 billion km (11 billion mi; 114.3 AU) from Earth. It is traveling south out of the plane of the planets, and is expected to enter interstellar space in a few years. And much like Voyager 1, it is also studying how the heliosphere interacts with the surroundings interstellar medium, using a suite of instruments that measure charged particles, magnetic fields, radio waves and solar wind plasma.

Once Voyager 2 crosses into interstellar space, both probes will be able to sample the medium from two different locations simultaneously. This is expected to tell us much about the magnetic environment that encapsulates our system, and will perhaps teach us more about the history and formation of the Solar System. On top of that, it will let us know what kinds of hazards a possible interstellar mission will have to contend with.

Illustration showing how NASA’s Hubble Space Telescope is looking along the paths of NASA’s Voyager 1 and 2 spacecraft as they journey through the solar system and into interstellar space. Credit: NASA/ESA/Z. Levy (STScI)

The fact that the two probes are still active after all this time is nothing short of amazing. As Edward Stone – the David Morrisroe Professor of Physics at Caltech, the former VP and Director of NASA’s Jet Propulsion Laboratory, and the Voyager project scientist – said:

“None of us knew, when we launched 40 years ago, that anything would still be working, and continuing on this pioneering journey. The most exciting thing they find in the next five years is likely to be something that we didn’t know was out there to be discovered.”

Keeping the probes going has also been a challenge since the amount of power they generate decreases at a rate of about four watts per year. This has required that engineers learn how to operate the twin spacecraft with ever-decreasing amounts of power, which has forced them to consult documents that are decades old in order to understand the probes’ software and command functions.

Luckily, it has also given former NASA engineers who worked on the Voyager probes the opportunity to offer their experience and expertise. At present, the team that is operating the spacecraft estimate that the probes will run out of power by 2030. However, they will continue to drift along their trajectories long after they do so, traveling at a distance of 48,280 km per hour (30,000 mph), covering a single AU every 126 days.

The Voyager 1 spacecraft has started to transverse what JPL has dubbed as a “cosmic purgatory” between our solar system – and interstellar space. Credit: NASA/JPL

At this rate, they will be within spitting distance of the nearest star in about 40,000 years, and will have completed an orbit of the Milky Way within 225 million years. So its entirely possible that someday, the Golden Records will find their way to a species capable of understanding what they represent. Then again, they might find their way back to Earth someday, informing our distant, distant relatives about life in the 20th century.

And if the craft avoid any catastrophic collisions and can survive in the interstellar medium of space, it is likely that they will continue to be emissaries for humanity long after humanity is dead. It’s good to leave something behind!

Further Reading: NASA

The post NASA Voyager Probes Still Going Strong After 40 Years appeared first on Universe Today.

NASA's Solar Dynamics Observatory Watches a Sunspot

NASA's Solar Dynamics Observatory Watches a Sunspot: On July 5, 2017, NASA’s Solar Dynamics Observatory watched an active region — an area of intense and complex magnetic fields — rotate into view on the Sun. This image shows a blended view of the sunspot in visible and extreme ultraviolet light, revealing bright coils arcing over the active region — particles spiraling along magnetic field lines.

Original enclosures:

NEBULA - Pelican Nebula Close Up

Pelican Nebula Close Up:

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 August 3

Pelican Nebula Close-up

Image Credit & Copyright: Sara Wager


Explanation: The prominent ridge of emission featured in this vivid skyscape is designated IC 5067. Part of a larger emission region with a distinctive shape, popularly called The Pelican Nebula, the ridge spans about 10 light-years and follows the curve of the cosmic pelican's head and neck. Fantastic, dark shapes inhabiting the view are clouds of cool gas and dust sculpted by energetic radiation from young, hot, massive stars. But stars are also forming within the dark shapes. Twin jets emerging from the tip of the long, dark tendril left of center are the telltale signs of an embedded protostar cataloged as Herbig-Haro 555 (HH 555). In fact, other Herbig-Haro objects indicating the presence of protostars are found within the frame. The Pelican Nebula itself, also known as IC 5070, is about 2,000 light-years away. To find it, look northeast of bright star Deneb in the high flying constellation Cygnus.

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Bad News For Proxima b: An Earth-Like Atmosphere Might Not Survive There

Bad News For Proxima b: An Earth-Like Atmosphere Might Not Survive There:

Back in of August of 2016, the existence of an Earth-like planet right next door to our Solar System was confirmed. To make matters even more exciting, it was confirmed that this planet orbits within its star’s habitable zone too. Since that time, astronomers and exoplanet-hunters have been busy trying to determine all they can about this rocky planet, known as Proxima b. Foremost on everyone’s mind has been just how likely it is to be habitable.

However, numerous studies have emerged since that time that indicate that Proxima b, given the fact that it orbits an M-type (red dwarf), would have a hard time supporting life. This was certainly the conclusion reached in a new study led by researchers from NASA’s Goddard Space Flight Center. As they showed, a planet like Proxima b would not be able to retain an Earth-like atmosphere for very long.

Red dwarf stars are the most common in the Universe, accounting for an estimated 70% of stars in our galaxy alone. As such, astronomers are naturally interested in knowing just how likely they are at supporting habitable planets. And given the distance between our Solar System and Proxima Centauri – 4.246 light years – Proxima b is considered ideal for studying the habitability of red dwarf star systems.

This infographic compares the orbit of the planet around Proxima Centauri (Proxima b) with the same region of the Solar System. Credit: Pale Red Dot

On top of all that, the fact that Proxima b is believed to be similar in size and composition to Earth makes it an especially appealing target for research. The study was led by Dr. Katherine Garcia-Sage of NASA’s Goddard Space Flight Center and the Catholic University of America in Washington, DC. As she told Universe Today via email:

“So far, not many Earth-sized exoplanets have been found orbiting in the temperate zone of their star. That doesn’t mean they don’t exist – larger planets are found more often, because they are easier to detect – but Proxima b is of interest because it’s not only Earth-sized and at the right distance from its star, but it’s also orbiting the closest star to our Solar System.”

For the sake of determining the likelihood of Proxima b being habitable, the research team sought to address the chief concerns facing rocky planets that orbit red dwarf stars. These include the planet’s distance from their stars, the variability of red dwarfs, and the presence (or absence) of magnetic fields. Distance is of particular importance, since habitable zones (aka. temperate zones) around red dwarfs are much closer and tighter.

“Red dwarfs are cooler than our own Sun, so the temperate zone is closer to the star than Earth is to the Sun,” said Dr. Garcia-Sage. “But these stars may be very magnetically active, and being so close to a magnetically active star means that these planets are in a very different space environment than what the Earth experiences. At those distances from the star, the ultraviolet and x-ray radiation may be quite large. The stellar wind may be stronger. There could be stellar flares and energetic particles from the star that ionize and heat the upper atmosphere.”

At one time, Mars had a magnetic field similar to Earth, which prevented its atmosphere from being stripped away. Credit: NASA

In addition, red dwarf stars are known for being unstable and variable in nature when compared to our Sun. As such, planets orbiting in close proximity would have to contend with flare ups and intense solar wind, which could gradually strip away their atmospheres. This raises another important aspect of exoplanet habitability research, which is the presence of magnetic fields.

To put it simply, Earth’s atmosphere is protected by a magnetic field that is driven by a dynamo effect in its outer core. This “magnetosphere” has prevented solar wind from stripping our atmosphere away, thus giving life a chance to emerge and evolve. In contrast, Mars lost its magnetosphere roughly 4.2 billion years ago, which led to its atmosphere being depleted and its surface becoming the cold, desiccated place it is today.

To test Proxima b’s potential habitability and capacity to retain liquid surface water, the team therefore assumed the presence of an Earth-like atmosphere and a magnetic field around the planet. They then accounted for the enhanced radiation coming from Proxima b. This was provided by the Harvard Smithsonian Center for Astrophysics (CfA), where researchers determined the ultraviolet and x-ray spectrum of Proxima Centauri for this project.

From all of this, they constructed models that began to calculate the rate of atmospheric loss, using Earth’s atmosphere as a template. As Dr. Garcia-Sage explained:

“At Earth, the upper atmosphere is ionized and heated by ultraviolet and x-ray radiation from the Sun. Some of these ions and electrons escape from the upper atmosphere at the north and south poles. We have a model that calculates how fast the upper atmosphere is lost through these processes (it’s not very fast at Earth)… We then used that radiation as the input for our model and calculated a range of possible escape rates for Proxima Centauri b, based on varying levels of magnetic activity.”

Artist’s impression of the surface of the planet Proxima b orbiting the red dwarf star Proxima Centauri. The double star Alpha Centauri AB is visible to the upper right of Proxima itself. Credit: ESO

What they found was not very encouraging. In essence, Proxima b would not be able to retain an Earth-like atmosphere when subjected to Proxima Centauri’s intense radiation, even with the presence of a magnetic field. This means that unless Proxima b has had a very different kind of atmospheric history than Earth, it is most likely a lifeless ball of rock.

However, as Dr. Garcia-Sage put it, there are other factors to consider which their study simply can’t account for:

“We found that atmospheric losses are much stronger than they are at Earth, and the for high levels of magnetic activity that we expect at Proxima b, the escape rate was fast enough that an entire Earth-like atmosphere could be lost to space. That doesn’t take into account other things like volcanic activity or impacts with comets that might be able to replenish the atmosphere, but it does mean that when we’re trying to understand what processes shaped the atmosphere of Proxima b, we have to take into account the magnetic activity of the star. And understanding the atmosphere is an important part of understanding whether liquid water could exist on the surface of the planet and whether life could have evolved.”

So it’s not all bad news, but it doesn’t inspire a lot of confidence either. Unless Proxima b is a volcanically-active planet and subject to a lot of cometary impacts, it is not likely be temperate, water-bearing world. Most likely, its climate will be analogous to Mars – cold, dry, and with water existing mostly in the form of ice. And as for indigenous life emerging there, that’s not too likely either.

These and other recent studies have painted a rather bleak picture about the habitability of red dwarf star systems. Given that these are the most common types of stars in the known Universe, the statistical likelihood of finding a habitable planet beyond our Solar System appears to be dropping. Not exactly good news at all for those hoping that life will be found out there within their lifetimes!

But it is important to remember that what we can say definitely at this point about extra-solar planets is limited. In the coming years and decades, next-generation missions – like the James Webb Space Telescope (JWST) and the Transiting Exoplanet Survey Satellite (TESS) –  are sure to paint a more detailed picture. In the meantime, there’s still plenty of stars in the Universe, even if most of them are extremely far away!

Further Reading: The Astrophysical Journal Letters

The post Bad News For Proxima b: An Earth-Like Atmosphere Might Not Survive There appeared first on Universe Today.

How the discovery of a hot Jupiter's stratosphere could help the search for life on other planets

How the discovery of a hot Jupiter's stratosphere could help the search for life on other planets:

For the first time ever, an exoplanet located 880 light-years away was found to have a stratosphere — a layer in the upper atmosphere where the temperature increases the higher up you go. The discovery may help astronomers refine the techniques that could lead to the discovery of alien life on other exoplanets.

The planet, described in a study published today in Nature, is called WASP-121b. It belongs to a class of exoplanets called hot Jupiters — worlds that are so big and hot that they are fairly easy to study, thus allowing astronomers to hone their skills and confirm their theories. Today's discovery confirms what astronomers suspected: super hot gas giants outside our Solar System can have a stratosphere.

WASP-121b is massive — nearly twice the size of our Jupiter. And because it orbits much closer to its host star than Mercury orbits around the Sun, its atmosphere heats up to more than 4,500 degrees Fahrenheit. (At that temperature, you could boil iron.) Using NASA’s Hubble Space Telescope, the researchers were able to detect glowing water molecules in the planet’s atmosphere, a clear signal that WASP-121b has a stratosphere. What exactly is causing the stratosphere is more of a mystery, but it could be gases like vanadium oxide and titanium oxide, which are believed to act like the ozone on Earth, the study says.

On Earth, the lower atmosphere is divided into two regions: the troposphere, which is closer to the surface, and the stratosphere, which is the upper layer. The stratosphere contains ozone, which absorbs harmful ultraviolet radiation from the Sun and heats up the stratosphere in the process. That means that, while the temperature decreases the higher up you go in the troposphere, in the stratosphere, the higher up you go, the temperature gets warmer. Most other planets in our Solar System — like Mars, Jupiter, Saturn, and even moons like Saturn’s Titan — have stratospheres. (On Jupiter and Titan, for instance, methane is responsible for them.) So astronomers have long thought that planets outside our Solar System would also have one.

How Earth’s stratosphere works. Image: News & Views by Kevin Heng / Nature


On hot Jupiters, scientists believe that stratospheres are created by chemicals like vanadium oxide and titanium oxide, which absorb radiation from stars and exist as gases only at the highest temperatures. But up until now, scientists hadn’t been able to find conclusive evidence that stratospheres on exoplanets exist. “The fact that we hadn't seen any [stratosphere] where we expected we would was challenging our expectations,” Michael Line, an assistant professor in the School of Earth and Space Exploration at Arizona State University, who wasn’t involved in the study, tells The Verge. So finally finding one is very exciting.

To study WASP-121b, the researchers looked at how the planet’s brightness changed at different wavelengths of light. They saw that water molecules in WASP-121b’s upper atmosphere were glowing and emitting light instead of absorbing light. That means there’s a layer of hot water gas up there, not a cooler layer that’d be expected if there’s no stratosphere. The change in temperature within WASP-121b’s stratosphere is extreme: about 1,800 degrees Fahrenheit. For reference, on planets in our Solar System, the change in temperature is usually less than 212 degrees Fahrenheit. “It’s some of the best evidence to date of a stratosphere in an exoplanet,” lead author Thomas Evans, a research fellow at the University of Exeter, tells The Verge.

An illustration of WASP-121b. Image: NASA, ESA, and G. Bacon (STSci)


There’s still a lot we don’t understand about WASP-121b and its atmosphere. For starters, we don’t know exactly what’s causing the stratosphere, Evans says. The researchers were able to detect vanadium oxide and some titanium oxide, but the data was not conclusive. The discovery also raises questions about other similar hot Jupiters that were found to have no stratosphere, says Thomas Beatty, a postdoc at the Center for Exoplanets and Habitable Worlds at Penn State, who did not take part in the study. Why does WASP-121b have a stratosphere, and others don’t? What’s really going on in WASP-121b’s atmosphere?

The field of exoplanet research is just at the beginning, and part of it focuses on finding traces of life outside of our Solar System. Worlds like WASP-121b are way too hot to possibly host any kind of life as we know it — whether or not they have a stratosphere. But studying them is still key: it allows researchers to test their theories and learn more about the underlying physics. “They are a first step towards honing our skills, developing our tools, getting ready for the things that are more Earth-like,” says Kevin Heng, the director of the Center for Space and Habitability at the University of Bern. “This is the first step in a long road.”

It’s a bit like playing Super Mario Bros. 3, says Line at Arizona State University. In the game, you can use a Warp Whistle and skip levels to get to the game's final world. But without going through all the levels, learning skills and collecting tools, you have a slim chance of beating Bowser at the end. Studying planets like WASP-121b is like going through all those levels: it allows astronomers to build their knowledge, so when we have an Earth-like planet that could host life, we’re better prepared to study it. “You don’t want to skip [hot Jupiters] along your journey because you want to build your tools,” Line says. “So when we think we’re measuring biosignatures on maybe a terrestrial planet, we’ll have a better understanding of the underlying physics that could possibly trip us up.”

Next, Evans wants to keep observing WASP-121b for longer periods of time. Eventually, he hopes to study the planet using NASA’s James Webb Space Telescope, which will launch next year and will be the most powerful space telescope ever built. JWST will allow astronomers to make even more precise measurements, and hopefully it’ll solve the mystery of what’s causing the stratosphere on WASP-121b. “James Webb is going to be the so-called game-changer,” Line says. “The amount of data per planet is going to be orders of magnitudes greater.”

How do you make a jellyfish wear an activity tracker?

How do you make a jellyfish wear an activity tracker?:

Spying on a jellyfish isn’t an easy task. Jellyfish are hard to see, fragile, and, worst of all, they’re gooey. Those traits make it tough to stick a tracking tag on them. But thanks to glue, suction cups, and cable ties, scientists are finally able to watch what jellies are up to beneath the waves.

Jellyfish are an important food source for hundreds of fish and endangered sea turtles. But they can also be a nuisance when their populations balloon and the stinging creatures wash up on beaches. The problem is, scientists know very little about these mysterious blobs of goo, like where they like to live, what they do, and what makes their populations burst into these destructive blooms.

The best way to watch an underwater creature without having to hold your breath is to stick some kind of tracking tag on it, which can be tricky to do. These tags act like souped-up Fitbits that track an animal’s route, record its activity, and monitor water conditions around it. On a shark, a tag can wrap snuggly around a fin. And on a seal, it can sit sturdily on its head. But how do you tag a jellyfish?

It turns out, there’s more to a jellyfish’s body than just, “jelly and mucus,” says Monterey Bay Aquarium Research Institute scientist Kakani Katija in a blog post published yesterday. “It actually has some heft and structure.”

That means it’s possible to stick a tag to the top of a jellyfish’s bell with surgical glue. These can last for up to a month. For shorter deployments, a suction cup can do the trick for a couple hours, according to the definitive guide to jellyfish tagging published last year by scientists from Stanford and the Monterey Bay Aquarium Research Institute.

For long-limbed species like the barrel jellyfish, it’s actually possible to wrap a tag around the stalk between the jellyfish’s bell and its arms like a bracelet. Depending on the species, these tags can last hours to days. The main advantage with this method is that the jellyfish can stay safely in the water during the tagging process. (If the jellyfish is dangerous to humans, it’s a bad idea to actually touch the jellyfish while doing this, the paper advises.)

Scientists have managed to successfully tag nine of the 200 species of jellyfish in the world so far, but there’s a lot more to learn. One of the barriers can be actually finding the jellyfish to tag, Wyatt Patry, an aquarist at the Monterey Bay Aquarium, said in a blog post. When jellyfish swim too deep for the would-be taggers to reach them, his team uses the “jelly donut” technique, Patry said. They drive a boat in a circle, or donut, around the cluster of jellyfish to generate a current that pushes the jellies to the surface.

It sounds like a lot of work. But don’t worry — for the rest of us amateur jelly fans without the scientific know-how or boat-driving skills, there’s always the Monterey Bay Aquarium’s Jelly Cam, just a click away.

Could Breakthrough Starshot be humanity’s first interstellar mission?

Could Breakthrough Starshot be humanity’s first interstellar mission?:

Artist’s impression of Breakthrough Starshot spacecraft on its way to Alpha Centauri. Image Credit: Breakthrough Initiatives

In the NewSpace era, one hears all manner of predictions and brash claims, but few come to fruition. Most of these efforts see Chapter 11 before they ever take to the skies. One program, dubbed Breakthrough Starshot, is looking to send mankind’s space exploration efforts far beyond the Solar System by using the world’s smallest spacecraft.

On June 23, 2017, these spacecraft, called “Sprites”, which were funded through a 2011 Kickstarter campaign, were launched atop a PSLV-XL rocket. Well, actually, they piggybacked on OHB System AG’s “Max Valier” and “Venta” satellites.

These spacecraft redefine the meaning of the word “small”, encompassing 3.5-by-3.5 centimeters and weighing in at a whopping four grams. The company described the craft as “the world’s smallest fully functional space probes”.

“Eventually, every mission that NASA does may carry these sorts of nanocraft to perform various measurements,” Starshot’s Zac Manchester said via a company-issued release. “If you’re looking for evidence of life on Mars or anywhere else, for instance, you can afford to use hundreds or thousands of these things – it doesn’t matter that a lot of them might not work perfectly. It’s a revolutionary capability that will open up all sorts of opportunities for exploration.”

A prototype Breakthrough Starshot “Sprite” spacecraft. (Click to enlarge) Photo Credit: Zac Manchester / Breakthrough Initiatives

The company has caught the attention of Scientific American and other established organizations.

Despite its diminutive size, these Sprites have what they need to get the job done – each contains solar panels, computers, sensors, and radios that will allow them to carry out their various functions.

With engineers looking for ever smaller classifications to describe spacecraft by (“cube”, “small”, and “nano” being just some of the names that have been used to help classify these satellites), the company has dubbed Sprites as “the next step” in terms of spacecraft miniaturization. Built at Cornell University and incorporated into the Max Valier and Venta satellites (built by the Bremen-based OHB System AG), the Sprite is Manchester’s pride and joy.

These Sprites remain affixed to the satellites and could, one day, be used to explore further than mankind has been able to explore so far. By all accounts, these Sprites are performing as advertised, communicating back to stations located in California and New York. While having satellites piggyback their way to orbit is nothing new, this flight is meant to validate the spacecraft communications systems.

These systems would (most likely) be first used in three-dimensional antennas in deep space to monitor space weather that could threaten Earthly power-grids and orbiting spacecraft. So how would these Sprites enable interstellar space exploration?

Larger interplanetary probes would deploy “swarms” of Sprites around planets, moons, and asteroids. These would seek out promising locales that could contain desirable minerals or locations that could support life.

Breakthrough Starshot is just one of the efforts under Breakthrough Initiatives (which also includes Breakthrough Listen) and was announced by Yuri Milner and Stephen Hawking on April 12, 2016 (the same day of the month that Yuri Gagarin began his fateful voyage and the crew of STS-1 launched from Kennedy Space Center’s Launch Complex 39A).

The project is an engineering program designed to prove the concept of spacecraft which would be propelled by light and accelerated to about 20 percent of light speed and reach Proxima Centauri 4.2 light-years away in just over 20 years after their launch. The craft would target the exoplanet Proxima b and other planets in our nearest star system, Alpha Centauri. If everything goes as planned, the craft would capture images as well as measurements of those distant worlds.

“Breakthrough Starshot, the $100 million initiative aiming to send robotic missions to nearby stars by the mid-21st century, has achieved what might prove to be a ‘Sputnik moment’ in successfully lofting its first spacecraft – the smallest ever launched and operated in orbit,” Manchester said.

Video courtesy of Breakthrough

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ALIENS ? : Insider Fact Check: Is NASA hiring someone to protect Earth from aliens?

Insider Fact Check: Is NASA hiring someone to protect Earth from aliens?:

A recent rash of stories would have you believe that NASA is in need of someone who can defend the Earth from Alien attack. How accurate are these stories and what is the truth behind NASA’s Office of Planetary Protection? Image Credit: Twentieth Century Fox

It never fails. Let the news cycle get a little slow and someone decides to get creative with the facts. Such was the case on Wednesday, August 1, when supposedly credible and professional sites such as USA Today and Newsweek dropped the ball and resorted to good ole’ fashioned clickbait-ing. It was a sign of the times that highlighted the current state of journalism in the U.S.

According to USA Today, NASA is hiring a Planetary Protection Officer to Protect Earth from Alien Harm (note to USA Today’s editors, get a Thesaurus – you should always use synonyms instead of the using the same word over and over again). Of course, as soon as one clicks the link, they are hit up by a tsunami of ads.

Newsweek apparently opted to up the “ridiculous” ante by having a disco-themed score added to their video that leads their story on the subject (once you get past the advertising that is). Their article is likely to make Woodward and Bernstein blush with jealousy (or, more likely, embarrassment for what this story says about the current plight of their profession). One NASA official made his thoughts about the rash of articles that are spreading misinformation about the position plain.

Depictions showing aliens attacking Earth have nothing to do with NASA’s Office of Planetary Protections, making their use 100 percent false. With their use, the decline that journalistic ethics has been on – continues to erode. Image Credit: Nathan Moeller / SpaceFlight Insider

“While I’m far from hopping on a ‘fake news’ bandwagon, I am growing [tired] of legitimate media trivializing stories, such as the most recent ‘NASA wants to pay someone $180k to protect us from aliens’,” NASA’s Deputy Associate Administrator for Communications Bob Jacobs said via a Facebook post. “Seriously, are we devolving into little more than clickbait media environment without any attention to fact?”

So what are the facts and is NASA actually looking for its own version of Will Smith and Tommy Lee Jones to defend us from aliens? In a word – no. According to the official post on USA Jobs, the Planetary Protection Officer’s duties include the following:

The Planetary Protection Officer (PPO) is responsible for the leadership of NASA’s planetary protection capability, maintenance of planetary protection policies, and oversight of their implementation by NASAs space flight missions. The PPO also supports the Safety and Mission Assurance (SMA) Technical Authority and serves as a principal advisory resource for the Chief, SMA and other senior officials on matters pertaining to planetary protection. The PPO is the Agency’s focal point for interactions with external organizations on matters related to planetary protection. Primarily the Planetary Protection Officer performs the following:

Leads planning and coordination of activities related to NASA mission planetary protection needs. Leads independent evaluation of, and provides advice regarding, compliance by robotic and human spaceflight missions with NASA planetary protection policies, statutory requirements and international obligations.

Advises the Chief, SMA and other officials regarding the merit and implications of programmatic decisions involving risks to planetary protection objectives. In coordination with relevant offices, leads interactions with COSPAR, National Academies, and advisory committees on planetary protection matters. Recommends and leads the preparation of new or revised NASA standards and directives in accordance with established processes and guidelines.

In essence, the job makes sure that any potential contamination that comes in from the probes NASA sends out into the solar system – does not come back with extraterrestrial biological contamination. So, think less Independence Day and more Andromeda Strain.

In terms of what the office does, their duty is to ensure that unknown and potentially hazardous organisms don’t find their way back to Earth. The office also works to preserve life that has evolved on distant worlds or in the oceans of moons in our own solar system. Spacecraft such as Galileo, that orbited the gas giant Jupiter and Cassini (which has been in operation around the ringed planet Saturn Since July of 2004) – have and will end by taking plunges into the clouds of these massive worlds (Galileo was safely deorbited in 2003).

Are you musing at this point that our response to the “reporting” that has appeared on this subject is too harsh? Business Insider used art from the 1996 Twentieth Century Fox film Independence Day to promote this article, you know, giant spaceship, over New York, shooting a death ray (no we’re not joking). How one can tie a job posting about a science position where one considers biological contamination issues to a ginormous alien death machine destroying New York – defies all definitions of honesty.

What makes the so-called reporting on this matter all the more disappointing is the fact that it isn’t even a new position. It has been around for at least a decade, with people actually handling the responsibilities of the position for much longer.

While Jacobs might not have much time for bloggers pretending to be journalists, he had some salient points about NASA’s Office of Planetary Protection.

“Consider how many people have the technical and scientific credentials to execute the job. By the way, if you know of anyone qualified, encourage them to apply. Let’s leave the alien hunting to someone on the SyFy channel,” Jacobs told SpaceFlight Insider, denoting why the position pays so well.

The mainstream media no longer has qualms about hunting down a teenage blogger for making a funny meme that mocked them, nor do they see anything wrong about posting pictures of the ‘Greys’ working out at Area 51 in regards to a story about the prevention of possible biological contamination. Perhaps the reporting originated from the same place where those Greys tend to use their probes. While the over-sensationalizing of this mundane job listing might achieve the short term goal of gaining them a few more clicks – it also means the continued degradation of how the public views the media.

Video courtesy of NASA

The views expressed in this article are those of the author and do not, necessarily reflect those of SpaceFlight Insider

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Stellar radiation may preclude Earth-like atmosphere on Proxima b

Stellar radiation may preclude Earth-like atmosphere on Proxima b:

This artist’s impression shows a view of the surface of the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. The double star Alpha Centauri AB also appears in the image. Proxima b is a little more massive than the Earth and orbits in the habitable zone around Proxima Centauri, where the temperature is suitable for liquid water to exist on its surface. Image & Caption Credit: ESO / M. Kornmesser

The exoplanet closest to the Solar System, Proxima b, is located in its star’s habitable zone but may be unable to support life because radiation from its host star is likely to strip away its atmosphere, according to a new study based on a computer simulation.

A group of scientists led by Katherine Garcia-Sage of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, created a computer model that placed Earth’s atmosphere, magnetic field, and gravity at the location of Proxima b. Using data obtained by NASA’s Chandra X-ray Observatory, they determined the level of radiation emitted by the host star, Proxima Centauri. Their goal was to determine the fate of Earth if it orbited in Proxima b’s location.

At its orbit, the exoplanet Proxima b likely couldn’t sustain an Earth-like atmosphere. Credits: NASA’s Goddard Space Flight Center / Mary Pat Hrybyk-Keith

The nature of the real Proxima b’s atmosphere is unknown because scientists have not observed the planet passing in front of its star. Observation of transits is the method researchers use to learn about planets’ atmospheres.

“We decided to take the only habitable planet we know of so far – Earth – and put it where Proxima b is,” Garcia-Sage said.

A star’s habitable zone is defined as the distance an orbiting planet can have liquid water on its surface. However, being in a habitable zone does not guarantee a planet is habitable.

To be habitable for life as we know it, a planet must have an atmosphere – one that regulates climate, maintains a surface pressure capable of supporting liquid water, enables the presence of life’s chemical building blocks, and protects it from dangerous radiation and space weather.

Significantly closer to its star than Earth is to the Sun, Proxima b is subject to the star’s regular flares and intense radiation hundreds of times the amount Earth receives from the Sun. In the computer model, that radiation stripped away the planet’s atmosphere at a rate up to 10,000 times greater than solar radiation does to Earth.

Red dwarf stars like Proxima Centauri and TRAPPIST-1, another star with planets in its habitable zone, emit extreme ultraviolet radiation, which ionizes gases in the atmosphere of an orbiting planet. The process removes electrons from its atmosphere, creating a stream of electrically-charged particles that are energetic enough to completely escape the planet’s gravity.

The high level of radiation that planets such as Proxima b are exposed to is enough to strip away heavier elements in an atmosphere, such as nitrogen and oxygen, in addition to hydrogen.

“This was a simple calculation based on average activity from the host star,” Garcia-Sage said. “It doesn’t consider variations like extreme heating in the star’s atmosphere or violent stellar disturbances to the exoplanet’s magnetic field – things we’d expect provide even more ionizing radiation and atmospheric escape.”

Two other factors that could affect the rate of atmospheric loss were also inputted into the computer model. These are the temperature of the planet’s neutral atmosphere, also known as its thermosphere, as well as the size of the area on the planet that experiences atmospheric escape.

Stellar radiation was found to heat up the thermosphere, increasing the rate of atmospheric loss. Areas on a planet over which atmosphere is lost are known as polar caps. The level of atmospheric escape is affected by a planet’s magnetic field lines. If the magnetic field lines at a planet’s magnetic poles are closed, the size of the polar cap is limited, and charged particles remain trapped, reducing the escape level. In contrast, if magnetic field lines are open, the escape rate of charged particles increases.

If Proxima b’s thermosphere has very high temperatures and its magnetic field must remain open, it could lose an atmosphere equivalent to Earth’s in just 100 million years. Low thermosphere temperatures and a closed magnetic field extend the duration it would take to lose an Earth atmosphere to slightly more than two billion years.

Proxima b is estimated to be approximately four billion years old.

Jeremy Drake of the Harvard-Smithsonian Center for Astrophysics, who took part in the study, said the level of atmospheric loss on Proxima b makes its habitability “implausible” and calls into question the habitability of Earth-like planets orbiting other red dwarf stars. These cool stars, the most common in the galaxy, have topped scientists’ searches for habitable worlds.

NASA’s Nexus for Exoplanet System Science (NExSS) coalition, which is charged with searching for life on exoplanets, and NASA’s Astrobiology Institute contributed to the study. Those findings are published in The Astrophysical Journal Letters.



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Rogue 'Double Planet' Is Actually 2 Failed Stars

Rogue 'Double Planet' Is Actually 2 Failed Stars:

The brown dwarf binary 2MASS J11193254−1137466.

Credit: W. Best et al.

A pair of objects drifting in interstellar space may look like a rogue "double planet," but it's actually two failed stars, a new study finds.The duo is the most lightweight binary system ever discovered and may be the closest approximation of a free-floating "double planet" that astronomers have found so far.

The object, named 2MASS J11193254−1137466, is located about 95 light-years from Earth, in the constellation Hydra. A 2016 study suggested it was a free-floating planet-like body — a "rogue" object without a parent star.

This previous research estimated that the mass of this object, also known as 2M1119, was four to eight times that of Jupiter. This suggested it was a brown dwarf, also known as a failed star. [Brown Dwarfs: Strange Failed Stars of the Universe Explained (Infographic)]

Brown dwarfs, like regular stars, begin as clouds of gas and dust that collapse under their own gravity. However, brown dwarfs lack the mass to squeeze atoms enough to trigger nuclear fusion. Instead, they are not quite planets and not quite stars.

Now, with the aid of the Keck II telescope in Hawaii, scientists have found that 2M1119 is actually two brown dwarfs, of equal brightness, orbiting each other.

"The fact that it was a binary, not another boring single system, was completely new," study co-author Trent Dupuy, an astronomer at the University of Texas at Austin, told Space.com. "Maybe it means that planetary-mass objects can form like stars and also, very rarely, form like binary stars."

To learn more about this binary, the researchers analyzed a collection of a few dozen 10-million-year-old stars located about 23 light-years from the pair. Known as the TW Hydrae Association, this is the youngest group of stars near Earth's solar system. It measures about 260 light-years across and, as a whole, is about 130 to 195 light-years from Earth, Dupuy said.

Based on the position and motion of 2M1119, the scientists found that there was an 82 percent chance that it was a member of the TW Hydrae Association. This suggested that 2M1119, too, was about 10 million years old. This knowledge, in combination with the spectrum of light detected from 2M1119, helped the researchers calculate other properties of the brown dwarfs.

The scientists estimated that the brown dwarfs in this pair are separated by about 334 million miles (538 million kilometers), or slightly less than four times the distance between Earth and the sun. The mass of each brown dwarf is about 3.7 times that of Jupiter, which makes the pair the lowest-mass binary system discovered to date outside Earth's solar system.

A newly scrutinized brown-dwarf binary system appears to be a member of the so-called TW Hydrae Association, about two dozen young stars that move together near the sun's neighborhood.

Credit: David Rodriguez/University of Western Ontario/Carnegie Institution of Washington DTM


"No one has ever found a binary brown dwarf that has components that are this low in mass," said study lead author William Best, an astronomer at the University of Hawaii at Honolulu. "We weren't sure a binary like this could even exist."

Whether these newfound bodies should be called planets or brown dwarfs is a tricky question, Best said.

"The components of 2M1119 fit the International Astronomical Union definition for planet — less than 13 Jupiter masses — and similar single objects have recently been called 'lonely planets' or 'rogue planets,'" Best told Space.com. "But we also commonly think of planets as things that are orbiting stars. In that sense, 'rogue planets' are not planets at all because they are not orbiting stars — they are floating out in space by themselves, and almost certainly formed like stars do. So, objects like this challenge our definitions of planet and brown dwarf.

"Bottom line — 2M1119 does not obviously fit into either of the planet and brown dwarf boxes," Best added. "I think the most accurate description for 2M1119 is 'planetary-mass binary brown dwarf.' I realize that's an unpoetic mouthful — 'lonely double planet' is certainly prettier. Hopefully, we'll develop a better definition in the future."

Brown dwarfs are thought to form the way stars do, Best said. "One open question in astronomy is, 'What is the smallest-mass brown dwarf that can form, and what is the lowest-mass binary that can form — that is, how low can star formation go?'" Best said. "This discovery sets a new record for binaries. Anyone working on the theory of how stars and brown dwarfs form needs to be able to explain how this binary formed. And there may be even lower-mass ones out there."

The scientists detailed their findings online June 23 in The Astrophysical Journal Letters.

Follow Charles Q. Choi on Twitter @cqchoi. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.

Saturn Basks in Sunlight in Spectacular Summer Solstice View (Photo)

Saturn Basks in Sunlight in Spectacular Summer Solstice View (Photo):

On July 31, 2017, NASA released an impressive vista of sunlight reflecting off of Saturn's northern hemisphere.

Credit: NASA/JPL-Caltech/Space Science Institute

Saturn emerges from the shadows to bathe in sunlight in a new view of the planet's infrequent summer solstice.

The Cassini spacecraft captured the beautiful photo of the ringed planet in April 2017. The image of Saturn's northern hemisphere includes lines across its cloudy atmosphere and a view of the hexagonal north pole outlined clearly. Cassini captured the sight when the spacecraft was 17 degrees above the ring plane and about 733,000 miles (1.2 million kilometers) above Saturn's surface.

Saturn experiences seasons, and Cassini has an "unparalleled opportunity" to observe how the giant belted planet responds to changes as it receives continuous light on its northern side, NASA officials said in a statement. A Saturn solstice occurs about once every 15 Earth years, and as Saturn approaches solstice at its north pole, the days in that hemisphere grow longer than at any other point along its roughly 30-Earth-year orbit. [More Photos: Saturn's Weird Hexagon Storms]

Saturn's northern hemisphere continues to receive most of the sun's light until the planet's equinox, when the sun shines equally over both halves of Saturn. After the photograph was taken, Saturn continued to receive more sunlight as Saturn's summer solstice officially arrived a month later, on May 24. [Cassini Spots 'Ghostly Curtains of Light' Near Saturn's South Pole]

The hexagonal vortex at Saturn's north pole changed color significantly between June 2013 (left) and April 2017 (right), as seen in views from the Cassini spacecraft. For the left image, each frame occurs approximately 130 minutes after the previous one, and for the right, each frame follows after an average of 230 minutes. Researchers combined images taken with the spacecraft's red, green and blue filters for the natural-color views.

Credit: NASA/JPL-Caltech/Space Science Institute/Hampton University


One seasonal change is a shift in color in the northern pole region. A few years ago, Cassini captured images with its wide-angle camera to show astronomers a distinct change in hue: from a darker tinge in November 2012 to a creamy tint in September 2016.

The spacecraft is operated by a collaborative mission of NASA, the European Space Agency and the Italian Space Agency. On Sept. 15, 2017, the spacecraft will complete a final dive into Saturn's atmosphere over the course of several orbits, to prevent the low-fueled spacecraft from spreading microbes to any of Saturn's moons.

Follow Doris Elin Salazar on Twitter @salazar_elin. Follow us @Spacedotcom, Facebook and Google+. Original article on Space.com.