Space News & Blog Articles

What happens when you slam a neutron star (or black hole, take your pick) into a companion star? A supernova, that’s what. And for the first time ever, astronomers think they’ve spotted one.

Back in 2014 the MAXI instrument aboard the International Space Station detected a flare of X-rays from a dwarf, star-forming galaxy sitting 480 million light-years away from us. No big deal; it happens all the time.

Around the same time, a radio survey using the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) called the Faint Images of the Radio Sky at Twenty centimeters (FIRST) didn’t find anything unusual in that patch of the sky. Also no big deal.

But then a follow-up survey, the Very Large Array Sky Survey (VLASS) which began observations in 2017, did find something: a bright source of radio emissions coming from the same place. Big deal.

The astronomers behind the survey think they’ve spotted something remarkable. A supernova detonation triggered by a massive case of stellar indigestion; a star consuming a companion black hole or neutron star.

How bad is the drought in the western United States? A stunning depiction of the record dry spell comes in images of Lake Mead, the reservoir formed by the Hoover Dam on the Colorado River. NASA satellite images, below, from Landsat 7 and Landsat 8 show the difference in lake levels between August 2000 and August 2021.

According to the U.S. Bureau of Reclamation, the water level in the reservoir — which supplies drinking water to millions of people in California, Arizona, Nevada, and part of northern Mexico — was measured at its lowest level since the lake was created with the damming of the Colorado River in 1935.

Data shows that as of August 22, 2021, Lake Mead was filled to just 35 percent of its capacity. The low water level comes at a time when 95 percent of the land in nine Western states is affected by some level of drought (64 percent is extreme or worse). It continues a 22-year megadrought that may be the region’s worst dry spell in twelve centuries.

The image from 2021 shows tan “fringes” along the shoreline in 2021, which are areas of the lakebed that would be underwater when the reservoir is filled closer to capacity. This phenomenon is often referred to as a “bathtub ring.”

The lake elevation data, shown below, says that at the end of July 2021, the water elevation at the Hoover Dam was 1067.65 feet (325 meters) above sea level, the lowest since April 1937, when the lake was still being filled. The elevation at the end of July 2000—around the time of the Landsat 7 images – was as 1,199.97 feet (341 meters).

New research shows that other sunlike stars in our galaxy aren’t so kind to their planets. Up to a quarter of them may consume planets before they even establish a solar system. That consumption leaves behind a distinct chemical fingerprint in the stars, which can help researchers understand how common planetary systems are…and how often they get destroyed.

Binary sunlike stars should be identical twins. They come from the same protostellar gas cloud. They formed with the same primordial soup of ingredients. They had similar formation histories, even to the point of having nearly the same size. They should look, act, and even smell the same.

But 25% of the time, they don’t. In those cases, one of the binary pair has a higher abundance of heavier elements than its twin. How could these differences arise?

One possibility, as described in a paper recently appearing in the preprint journal arXiv and submitted for publication in the journal Nature Astronomy, is that one of those sunlike stars in the binary pair has eaten its children.

It wouldn’t take much. Just a few Earth masses is enough to contaminate a star’s atmosphere to the point that we could detect those differences with our observations. The researchers behind the study examined 107 binary pairs of sunlike stars and found that planet engulfment was a scarily common scenario.

NASA is commonly thought of as America’s space agency, but its name also emphasizes another research area. The National Aeronautics and Space Administration is also America’s civilian aerospace research organization.  In that role, it has been instrumental in developing new technologies ranging from rocket engines to aircraft control systems.  Part of that role is running the Advanced Air Mobility (AAM) campaign to test autonomous drone technology.  The latest milestone in that campaign was testing an electric vertical takeoff and landing (eVTOL) helicopter intended for eventual use as an air taxi. 

The testing, which runs through September 10th, utilizes a yet-to-be-named eVTOL craft from a company called Joby, which has been developing the technology with NASA for over 10 years.  The aircraft, which looks like a large version of a 6-rotor drone, will be performing flight tests at Joby’s Electric Flight Base, near Big Sur in California.

This is the first round of testing with this novel type of aircraft.  NASA has a rigorous test plan to perform, including collecting data on the vehicle’s movement, noise, and communications in various forms of flight.  To collect some of the data, researchers had to develop a type of mobile acoustic center that could track the aircraft with 50 different microphones and collect data on the noise it would make.

Noise is an important factor in the adoption of autonomous VTOL flight – people have to accept it.  Noone would be happy with delivery drones taking off in their backyard if they created the same amount of noise at a jet engine.  But public acceptance isn’t the only factor influencing the testing.

Another is regulations.  While not directly responsible for regulating autonomous flight, NASA is a key partner for the Federal Aviation Administration (FAA), which is.  Some technology activists have already expressed concerns that the FAA is digging its heels in when dealing with a quickly evolving industry, potentially hindering the development of American companies as competitors in better regulatory regimes literally fly by them.

In ten days, SpaceX and the payment processing company Shift4Payments will be making history as four commercial astronauts board the Crew Dragon Resilience and fly to space. This mission, known as Inspiration4, will be the first all-civilian flight in history, the purpose of which will be to raise awareness, funds for St. Jude Children’s Research Hospital and inspire the next generation to seek out education and employment in the STEM fields.

In preparation for this moment in spaceflight history, the four-person crew got a chance to see a key piece of hardware that will make the mission special. This was the Crew Dragon cupola, a domed glass window that replaced the usual docking adapter on the front of the spacecraft. Before it was shipped off to Florida to be integrated with the rest of the spacecraft, the crew got a chance to peer through the dome and imagine what it will be like to do so in space!

This event, shared via Twitter, took place at the SpaceX headquarters in Hawthorne, California, this past Wednesday (Sept. 1st). One by one, the four-member crew got a chance to pose inside the cupola as part of a campaign to raise awareness about the first all-civilian flight. This mission will not only be a milestone in spaceflight. It also illustrates how commercial spaceflight and public-private partnerships are making space more accessible and beneficial.

This mission is named in recognition of the four-person crew that will go to space to raise awareness and funds for St. Jude Children’s Research Hospital. They include Mission Commander Jared Isaacman, Mission Pilot Dr. Sian Proctor, Medical Officer Hayley Arceneaux, and Mission Specialist Chris Sembroski. Each person was carefully selected based on the skills and experience they bring to the mission and represent a specific part of the overall theme.

Once the crew selection process was complete, and the winners announced in March of 2021, the four-member crew began the six-month training process in preparation for spaceflight. This included parabolic flights (aka. zero-g flights) to accustom them to the feeling of being weightless, altitude training (climbing Mount Ranier), centrifuge training, Dragon simulations, observations of other launch operations, and additional classroom, simulation, and medical testing.

The search for planets beyond our Solar System (extrasolar planets) has grown by leaps and bounds in the past decade. A total of 4,514 exoplanets have been confirmed in 3,346 planetary systems, with another 7,721 candidates awaiting confirmation. At present, astrobiologists are largely focused on the “low hanging fruit” approach of looking for exoplanets that are similar in size, mass, and atmospheric composition to Earth (aka. “Earth-like.”)

However, astrobiologists are also interested in finding examples of “exotic life,” the kind that emerged under conditions that are not “Earth-like.” For example, a team of astronomers from the University of Cambridge recently conducted a study that showed how life could emerge on ocean-covered planets with hydrogen-rich atmospheres (aka. “Hycean” planets). These findings could have significant implications for exoplanet studies and the field of astrobiology.

The research was led by Dr. Nikku Madhusudhan, a Reader in Astrophysics and Exoplanetary Science from the University of Cambridge’s Institute of Astronomy (IoA). He was joined by Ph.D. astrophysics student Anjali Piette (Dr. Madhusudhan is her supervisor) and fellow IoA member Dr. Savvas Constantinou. The study that describes their findings, titled “Habitability and Biosignatures of Hycean Worlds,” recently appeared in The Astrophysical Journal.

Life on Little Ice Giants?

Of all the exoplanets that have been discovered in the past 30 years, the vast majority have either been predominantly rocky planets several times the mass of Earth (“Super-Earths”) or ice giants with hydrogen-rich atmospheres (“mini-Neptunes”) or somewhere in between. Whereas Super-Earths account for about 30% (1,383) of all exoplanets discovered to date, mini-Neptunes are the most plentiful, accounting for 34% (1,531).

Most mini-Neptunes are over 1.7 and 3.9 times the size of Earth and are believed to have interiors composed of ice, rock, and oceans of volatile elements. Previous studies of such planets have found that the pressure and temperature conditions beneath their hydrogen-rich atmospheres would be too great to support life. However, in a previous study, Nikku Madhusudhan and his team found that these planets could support life under certain conditions.

A supernova is a brilliant end to a giant star. For a brief moment of cosmic time, a star makes one last effort to keep shining, only to fade and collapse on itself. The end result is either a neutron star or a stellar-mass black hole. We’ve generally thought that all stars above about ten solar masses will end as a supernova, but a new study suggests that isn’t the case.

Unlike the famous Type Ia supernovae, which can be caused by the merger or interaction of two stars, large stars undergo what is known as a core-collapse supernova. Stars survive through a balance of heat and pressure against gravity. As more elements are fused, a large star must generate heat by fusing ever heavier elements. Eventually, this forms a layer of regions where different elements are fused. But that chain can only be carried up to iron. After that, fusing heavier elements costs you energy rather than releases it. So, the core collapses, creating a shock wave that rips the star apart.

In models of large dying stars, core-collapse supernovae occur for stars above 9 – 10 solar masses, up to about 40 – 50 solar masses. Above that mass, stars are so massive that they likely collape into a black hole directly, without becoming a supernova. Extremely massive stars, on the order of 150 solar masses or more, might explode as a hypernova. These beasts don’t explode because of a core-collapse, but rather an effect known as pair instability, where colliding photons created in the core create pairs of electrons and positrons.

This new study suggests that the upper mass limit for core-collapse supernovae might be much lower than we thought. The team looked at the elemental abundances of a pair of colliding galaxies known as Arp 299. Because the galaxies are in the process of colliding, the region is a hotbed of supernovae. As a result, the elemental abundances of Arp 299 should be largely dependent on the elements cast off in supernova explosions. They measured the abundance ratio of iron to oxygen, and the ratios of neon and magnesium to oxygen. They found that the Ne/O and Mg/O ratios were similar to that of the Sun, while the Fe/O ratio was much lower than solar levels. Iron is cast into the universe most efficiently by large supernovae.

The ratios the team observed didn’t match standard core-collapse models, but they found that the data matched supernova models well if you excluded any supernova over about 23 – 27 solar masses. In other words, if stars collapse into black holes above about 27 solar masses, then models and observations agree.

I’d never seen galaxy images like this before. Nobody had! These images highlight star forming regions in nearby(ish) galaxies. There are still a number of unanswered questions surrounding how star formation actually occurs. To answer those questions, we are observing galaxies that are actively forming stars within giant clouds of gas. Until recently, we didn’t have the resolution needed to clearly image the individual gas clouds themselves. But images released by a project called PHANGS (Physics at High Angular resolution in Nearby GalaxieS) in a collaboration between the European Southern Observatory Very Large Telescope and the Atacama Large millimeter/submillmeter Array (ALMA) have provided never before seen detail of star forming clouds in other galaxies.

A Cloud of Stardust

Stars form from Giant Molecular Clouds (GMCs) which are mainly comprised of molecular Hydrogen (H2). Gas within these clouds collapses under gravity eventually becoming dense spheres. With the increase in density and pressure, heat within these spheres makes nuclear fusion possible fusing hydrogen into helium – a star is born! But what triggers the initial collapse of the gas? Does the star formation rate vary between different clouds in the same galaxy? How varied are the clouds themselves? These are all chapters of star formation we’re not entirely certain about. Enter PHANGS.

PHANGS researchers chose target galaxies using a number of preconditions. The galaxies had to be close enough so they could be imaged at the required resolution to see individual GMCs. All the targets are therefore within 17 million parsecs of the Milky Way (about 55 million light years). The galaxies are also not too inclined as to provide a clear line of sight into the disks of the target galaxies. And, perhaps most importantly, the target galaxies are actively forming stars. As “Main Sequence Galaxies” these galaxies are forming stars in their disks without the external gravitational interaction of a nearby galaxy or as a result of galaxy mergers both of which can trigger intense periods of star formation call star bursts. Rather these galaxies are forming stars through processes internal to the galaxy. 90 such galaxies met the criteria and were selected for the survey.

Cold and Dark

Discovering star forming regions in the targets galaxies is a achieved through a combination of finding cold gas as well as hot gases heated by newly formed stars. Cold GMCs birthing new stars are called stellar nurseries. They can range from tens to hundreds of lightyears in diameter with the mass equivalent to thousands of suns. However, the hydrogen these clouds are made from is difficult to see. When hydrogen is exposed to energy, it glows and is easily detectable while cold hydrogen hides in the darkness of space. But GMCs also contain carbon monoxide (CO) which in a cold state is easier to detect than hydrogen. The ratio of CO to hydrogen in GMCs is understood to be a constant and so the amount of detected CO molecule can tell us how much hydrogen is present in a given cloud. It’s this CO signal that ALMA hunts for.

Once hydrogen is excited by the energies of newly forming and young stars, it releases a light known as Hydrogen Alpha. H-alpha is is the brightest feature in the spectrum of glowing hydrogen and is how we observe much of the Universe. Combining the hot and cold maps of these GMCs in other galaxies reveals the environment in which stars are forming. An instrument called MUSE on the Very Large Telescope maps the glowing H-Alpha where ALMA detects the cold CO emissions. The finest details resolved by ALMA in the target galaxies are approximately 100 parsecs in diameter (about 326 light years). The researches note this is “cloud-scale” resolution as the target GMCs are also about 100 parsecs in diameter. At this resolution, the clouds can be distinguished as individual structures separate from the structures of the rest of their home galaxies.

In some applications, bigger lasers mean better lasers.  That is the case in astronomy, where lasers are used for everything from telescope calibration to satellite communication.  The European Southern Observatory (ESO) and some of its commercial partners have developed a laser 3 times more powerful than the existing industry standard.  With that increased power level, the new system has the potential to dramatically improve the way telescopes deal with one of the most fundamental problems in ground-based astronomy – atmospheric turbulence.

Regular atmospheric turbulence is commonplace on Earth and is the cause of what the human eye perceives as the stars “twinkling.”  However, to a telescope, turbulence that is unaccounted for could lead to entire data sets being thrown out.  Telescopes have a standard technique to eliminate any such effects – they calibrate using a known stable star.

The obvious problem is sometimes there are no stars they can use to calibrate to.  So scientists came up with a way of making an “artificial star” that would allow observatories to calibrate against a stable observable object no matter which direction they were facing.  That technique involves blasting sodium atoms 90 km up in the atmosphere with a laser.

Today that technology exists as the Four Laser Guide Star Facility, which operates the ESO’s Very Large Telescope (VLT).  Coming in at a respectable 22W of power, this calibration tool has been essential to the VLT’s successful operation.  However, the more powerful the laser brought to bear on the sodium atoms, the more stable the calibration “star.”  So ESO has bumped the power level up to 63W – almost a 3 fold increase over the existing system.

This wide-field image shows the CaNaPy laser being tested on-sky at the Allgäuer VolksSternwarte Ottobeuren observatory in Germany. The laser, based on ESO-patented technology, excites sodium atoms in the upper atmosphere, creating an artificial source that can be used to monitor and correct atmospheric turbulence. This laser will be eventually installed at the European Space Agency’s (ESA) Optical Ground Station in Tenerife, Spain, as part of a collaboration between ESO and ESA to use adaptive optics for astronomical and satellite communication purposes.
Credit – ESO

So much in the astronomy community revolves around the decadal survey.  Teams of dozens of scientists put hundreds of hours developing proposals that eventually try to impact the recommendations of the survey panel that influence billions of dollars in research funding over the following decade.  And right now is the prime time to get those proposals in.  One of the most ambitious is sponsored by a team led by researchers at John Hopkins University Applied Physics Laboratory (APL).  Their suggestion – it’s time to land on Mercury.

This isn’t the first time the idea has been aired, but new technologies make this incarnation feasible for the next decade.  The current proposal was first floated by APL scientists to NASA, which funded a mission concept study that produced an in-depth 82-page review of a mission outline that is available from NASA. 

There are five main mission objectives:

Any lander will face a daunting challenge in landing.  Currently, the best images we have of the innermost planet were captured by NASA’s MESSENGER spacecraft, which orbited Mercury from 2011–2015.  But these images cover only minimal parts of the surface, and their resolution is not ideal for selecting a specific landing site.  Each pixel in the highest-resolution images MESSENGER returned covered at best 2–3 m of the planet’s surface at best.

Graphic on the lander included in the report that shows potential scientific payloads, engineering requirements and orbital mechanics.
Credit – Ernst et al.

A leader in the ‘smartscope’ industry releases its exciting new eQuinox telescope.

It’s every amateur astronomer’s dilemma. If you’re like me, the basic equation of ‘should I observe tonight?’ is always up against the same basic equation: is the time and effort worth it? Living under bright downtown urban skies, my options are to either head to the parking garage rooftop (and be restricted to bright targets), or load up, drive for several hours, setup at a remote dark sky site, observe, then repeat the reverse process and head home in the early AM hours…

In the above scenario, the best telescope is the one you end up using most… and it’s in this capacity that Unistellar’s new eQuinox ‘smartscope’ excels. We had a chance to review their original eVscope last year, and the eQuinox is a very similar unit, with a few key innovations.

I’ve owned many telescopes of all types over the years, going back to some of the very first ‘goto’ units in the 80s… most of which, needed a little astronomical know-how to successfully get to a target on the first night out. I can say that Unistellar’s eQuinox works as advertised, right out of the box: simply secure the unit to the tripod, turn it on, connect it to your phone’s wifi, put it through a quick sky alignment (the unit uses plate-solving and GPS to know where it is and what it’s pointed at) and you’re off and running. Suddenly, with the eQuinox telescope, deep-sky targets are again in grasp, even from our downtown parking garage rooftop perch. For example, we managed to nab faint +11th magnitude comet T2 Palomar with the ‘scope, a target we’d never bother to go after from downtown.

Unlike other star-pattern alignment units, the eQuinox is also very forgiving. We found it was able to easily able to accurately align even under partly cloudy skies, just 30 minutes after sunset. The app gives the user suggested targets currently above the horizon, or you can custom enter the Right Ascension/Declination coordinates (great for comet hunting).

At one time, the idea of sending humans to Mars either seemed like a distant prospect or something out of science fiction. But with multiple space agencies and even commercial space companies planning to mount missions in the coming decade, the day when humans will go to Mars is fast approaching the point of realization. Before this can happen, several issues need to be resolved first, including a myriad of technical and human factors.

In any discussion about crewed missions to Mars, there are recurring questions about whether or not we can mitigate the threat of radiation. In a new study, an international team of space scientists addressed the question of whether particle radiation would be too great a threat and if radiation could be mitigating through careful timing. In the end, they found that a mission to Mars is doable but that it could not exceed a duration of four years.

The research was led by Mikhail Dobynde, a researcher from the Skolkovo Institute of Science and Technology and the Russian Academy of Science in Moscow. He was joined by members from the GFZ German Research Centre for Geosciences at the Helmholtz Centre Potsdam in Germany, the University of California Los Angeles (UCLA), and the Massachusetts Institute of Technology (MIT).

For the sake of their study, the team considered the threat posed by the two main types of radiation sources: Solar Energetic Particles (SEP) and Galactic Cosmic Rays (GCR). The former consists of fast-moving protons, electrons, and high-energy atomic nuclei that can negatively affect electronics and living tissue. The latter consists of the same range of energetic particles but originate beyond the Solar System and are attributed to supernovas.

The intensity of both of these radiation sources depends on the level of solar activity, where SEP levels are least intense during a solar minimum, but GCR activity is most enhanced. The reverse is also true, where GCR activity will be lowest during solar maximum, but SEP will be elevated. To gauge the threat posed by these sources, the team combined geophysical models that considered how particle radiation varies during the 11-year solar cycle.

Supply chains have been wreaking havoc across the industrial world.  The complex web that holds the world’s economies together has been fraying at the edges, resulting in some unexpected shortages, such as a lack of rental cars in Alaska and a lack of Lunchables at the author’s local grocery store.  Now there’s a supply shortage that directly ties to the pandemic that is starting to affect the space launch industry – oxygen.

It’s common knowledge at this point that liquid oxygen (LOX) is an important tool for combating severe symptoms of Covid-19.  Most patients admitted to the hospital with the virus need oxygen directly pumped into the lungs, usually supplied by LOX suppliers such as AirGas or other commercial gas companies.  Oxygen is also used in high quantities in a completely different application – rocket engines.

Chilled oxygen is a necessary propellant chemical for all the leading launch firms, including SpaceX, Virgin Orbit, and ULA.  But it’s becoming harder and harder to obtain the liquid form of the most abundant element in the Earth’s crust.  That’s in no small part because the same process used to create oxygen for rocket fuel can also create oxygen used for Covid patients.  And as Richard Craig, the vice president of technical and regulatory affairs for the Compressed Gas Association, put it: “People come first.”

Even avid space exploration fans wouldn’t disagree with that logic. But the spike in Covid cases over the summer is starting to tax the supply chain for oxygen.  It got to the point that both Gwynne Shotwell, SpaceX’s President, and Elon Musk, its CEO, spoke out about the potential impact a lack of oxygen could have on their flight schedule. Shotwell went so far as to directly ask conference-goers at the 36th Space Symposium to “send [her] an email” if they happen to have any liquid oxygen to spare.

She will be hard-pressed to find any in the home state of some of SpaceX’s launches. Florida is one of the hardest-hit states in the current resurgence of the pandemic.  LOX normally isn’t transported over far distances – most is created about 200-300 miles from where it is distributed. It is possible to transport the liquid further. However, another confounding factor impacts the intricate LOX supply chain – truck drivers.

It appears that the International Space Station is showing its age. Or, at least, the older modules that have been in space since 1998 certainly are. According to statements made by a senior Russian space official, cosmonauts aboard the ISS have discovered new cracks in the Functional Cargo Block (FCB) module – aka. Zarya (“Dawn”). These cracks were found in seven of the module’s twenty windows and could eventually threaten the entire station.

The Zarya module was the first component launched for the International Space Station. While funding was provided through a NASA subcontract with Boeing and the module is part of the US section, the module itself was built by the Khrunichev State Research and Production Space Center (KhSC) in Russia (a subsidiary of Energia Rocket and Space Corporation) and Roscosmos was responsible for launching it in 1998.

Zarya was also responsible for providing electrical power, storage, propulsion, and guidance to the ISS during the initial stage of assembly. Alas, after twenty-three years in space (and twenty-one in continuous operation), the module is beginning to suffer from its share of structural problems. And in space, the worst structural problem imaginable is to find cracks forming in the fuselage.

News of the issue came from Vladimir Soloviev, general designer of Energia RSC – which designed and built all of the modules in the Russian segment. As Soloviev told the Russian news agency RIA Novosti:

“Superficial fissures have been found in some places on the Zarya module. This is bad and suggests that the fissures will begin to spread over time… In this regard, we have introduced a new procedure for measuring the deflection of glass. They, of course, can be covered with sealed covers, but what is the point of flying at the station without windows?”

Dust on Mars gets everywhere – including on top of ice deposited during one of Mars’ previous ice ages.  Just how that dust affects the ice is still up for some debate. Adding to that debate, a recent paper by researchers at Arizona State University and the University of Washington has laid out a map between the dust content of a glacier and the brightness of its ice.

As with many climate-related interactions, the seemingly simple interface between the ice and dust is much more complicated than it appears.  The team used pictures from the Phoenix Mars Lander and the Mars Reconnaissance Orbiter to build a model that would predict how bright snow and ice would be here on Earth.  They then flipped that approach to estimate how the dust on Mars affects the brightness of ice deposits on the planet.

It turns out a lot of ice on Mars is covered in dust, and the color of that dust makes a huge difference to the ice it covers. Darker dust strains would attract more heat, making it more likely the ice it covers would melt.  Alternatively, ice that is not covered by dust is reflective, making it less likely to melt in the much weaker Martian sun.  

If any ice does melt due to the increased solar radiation it receives, the dust piled on top of it also makes the resulting water less likely to evaporate away into the Martian atmosphere.  So the Martian dust itself might play an important part in any Martian hydrological cycle.

So far, this is simply a theory backed up by some preliminary data collected by orbital satellites and one lander.  To gain further credibility, that theory will have to withstand the further scrutiny of ice samples collected off the planet’s surface in the future.  Either way, if humanity ever hopes to set up a permanent base on Mars, it will be important to understand how all the complex factors present on the red planet interact to create its local environment.

Brown dwarfs are strange things. They are in the middle ground between planets and stars. A star is defined as an object massive enough for helium to fuse into hydrogen into its core, while a planet is too small for core fusion to occur. It seems a simple distinction until you learn about fusion. Anything with a mass below about 13 Jupiters is too small for fusion to occur, and is thus a planet. If your mass is about about 80 Jupiters, then you can fuse helium and are therefore a star. But if your mass is between 13 and 80 Jupiters, things get interesting. You can’t fuse hydrogen to shine brightly, but you can fuse lithium into other elements. This is known as lithium burning. It doesn’t provide lots of energy, but it is technically nuclear fusion.

Because of this effect, brown dwarfs can be difficult to identify. Large and young brown dwarfs can be as hot and bright as a small star, while older or smaller brown dwarfs look like large planets. This is because, unlike stars, brown dwarfs cool down over time. They are often brightest at infrared wavelengths, and so they are often identified by their infrared spectrum.

The distribution of stars near Earth. Credit: NASA, ESA, and A. Feild (STScI)

But one odd aspect about brown dwarfs is that they seem to be rarer than they should be. When you count the number of stars in the local universe, yellow stars such as our Sun are more common than giant stars, and red dwarf stars are much more common than yellow ones. You would expect then that brown dwarfs are more common than red dwarfs. But so far we’ve found fewer brown dwarfs than even yellow stars. Part of that is due to the fact that brown dwarfs are cool and dim, but even when we take that into consideration we should see more of them. It’s known as the brown dwarf desert problem.

But an accidental discovery might be the solution to this mystery. It was discovered by NASA’s Near-Earth Object Wide-Field Infrared Survey Explorer (NEOWISE), and named “The Accident.” It is a brown dwarf that didn’t show up in sky surveys looking for brown dwarfs because it doesn’t look like a brown dwarf. Brown dwarfs can be identified by their infrared spectra, but each spectrum depends on the composition of the brown dwarf as well as its temperature. The spectrum of The Accident is odd because it’s dim where you’d expect it to be bright, and bright where it’s typically dim.

It’s no secret that China has become a major contender when it comes to spaceflight. In the past twenty years, the China National Space Agency (CNSA) has accomplished some historic firsts. This includes sending astronauts to space, deploying three space stations (as part of the Tiangong program), developing heavy launch vehicles (like the Long March 5), and sending robotic explorers to the far side of the Moon and Mars.

Looking ahead to the next decade and beyond, China is planning on taking even bolder steps to develop its space program. Among the many proposals the country’s leaders are considering for its latest 5-year plan, one involved creating an “ultra-large spacecraft spanning kilometers.” Having this spacecraft in Low Earth Orbit (LEO) would be a game-changer for China, allowing for long-duration missions and the utilization of space resources.

This proposal comes at a time when China has been achieving multiple milestones in space. Earlier this year, China became the second nation in the world to successfully land a rover on the surface of Mars and the first to land a mission that consisted of an orbiter, lander, and rover. Two years ago, China became the first nation to land a robotic mission on the far side of the Moon (the Chang’e-4 lander and rover).

This ambitious proposal was one of ten submitted by The National Natural Science Foundation of China at a meeting in Beijing earlier this month. Each of these projects has been awarded $2.3 million (the equivalent of ¥15 million) in funding to further research and development. One of the project’s main goals will reportedly be to find ways to keep the spacecraft’s mass down while ensuring they are structurally sound enough to launch to orbit.

According to the project outline published by the Chinese foundation – and cited by the South China Daily Mail (SCDM) – the spacecraft elements will be built on Earth and then launched individually to orbit to be assembled in space. The same outline specifies how this spacecraft will be “a major strategic aerospace equipment for the future use of space resources, exploration of the mysteries of the universe and staying in long-term.”

The Perseverance rover now has a new tool to help scientists and engineers to figure out where the rover goes next. The new tool is the little rotorcraft that was tucked away in the rover’s belly, the Ingenuity helicopter. Ingenuity has now started doing aerial surveys to scout ahead for Perseverance.

During its most recent flight, Ingenuity captured 10 color images ahead of the region where Perseverance is traversing, to help the team figure out whether the rover should remain in its current location and do more scientific investigations or drive to investigate potentially interesting rocks in the nearby “South Seítah” area.

“From a science perspective, these images of South Seítah are the most valuable Ingenuity has taken to date,” said Ken Farley, project scientist for NASA’s Perseverance rover. “And part of their value may be in what they are not showing. Sedimentary layers in rocks are not readily apparent in the image, and there may be areas that could be difficult to negotiate with the rover. There is work to do by our science and rover driving teams to understand better how to respond to the new data.”

Ingenuity took the images from an altitude of 33 feet (10 meters). The team said the flight – the helicopter’s 12th so far —  was one of the most complicated the helicopter team has executed so far. It was also the longest-duration flight to date (169.5 seconds) with multiple waypoints as it flew from relatively non-descript terrain outside South Seítah into much more varied terrain inside, and then back out again.

Perseverance itself has taken over 125,000 images in the six months since it landed on Mars. The images are incredible, and not only are they stunning pictures from another world, they also allow scientists to make observations of the rocks and Martian regolith. And the images are also important from an engineering perspective, in that they help the “rover drivers” determine the best path forward, based on what they see in the images.

A stunning new photograph from the Hubble Space Telescope shows a nearly perfect Einstein Ring, an effect caused by gravitational lensing. This is one of the most complete Einstein Rings ever seen.

Gravitational lenses occur when a massive object, such as a galaxy, is aligned directly between Earth and another massive object even farther away. Einstein predicted that gravity could bend light, and this image is a wonderful example of how gravity from foreground objects causes a deflection of light from background objects, forming a ring of light.

In this case, it’s not just one foreground galaxy and one background galaxy, but the gravity from two massive galaxies bending the light from a distant quasar, focusing the otherwise divergent light into a visible ring.

So why does this image show several points of light?

As you can see, clustered at the center of this image are six luminous spots of light, four of them forming a circle around a central pair. Hubble data also indicates that there is a seventh spot of light in the very center, which is a rare fifth image of the distant quasar. This rare phenomenon is caused by the presence of two galaxies in the foreground that act as a lens.

In the last two decades, we have all grown accustomed to rovers exploring Mars. At least one rover has been active on the planet every day since January 4, 2004, when NASA’s Spirit rover landed in Gusev crater. Opportunity (2004) and Curiosity (2012) followed, each making unique journeys of discovery of their own. Perseverance (2021) is the latest and greatest of these robotic explorers, boasting a state-of-the-art in-situ resource utilization experiment to extract oxygen from the atmosphere, an accompanying helicopter to scout the path ahead, and a suite of unparalleled geology instruments. But what really sets Perseverance’s mission apart is that, for the first time, it is collecting samples of Martian rock to bring back to Earth.

As advanced as Perseverance’s science instruments are, nothing beats the ability to study samples up close in a laboratory here on Earth. So Perseverance is making a rock collection. It is taking samples as its journeys across Jezero Crater, and leaving caches of the samples for a future mission to pick up and return to Earth (sometime in the mid-2020s).

At least, that’s the plan. But space exploration is never simple. As routine as rover activity on Mars has become in recent years, the red planet never ceases to surprise mission planners. Earlier this month, Perseverance made its first attempt at collecting a sample in one of its 43 titanium sampling tubes. After drilling the sample core, the team was shocked to discover that the sample tube remained empty, and was nowhere to be found on the ground around the rover, nor in the drill hole.

It turns out the rock into which Perseverance had drill was far softer than previously imagined, and the rock merely crumbled into powder beneath the drill. Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate told reporters “While this is not the ‘hole-in-one’ we hoped for, there is always risk with breaking new ground…I’m confident we have the right team working this, and we will persevere toward a solution to ensure future success.”

This week, that team is ready for a second attempt. Perseverance has positioned itself next to a new rock outcrop, nicknamed “Rochette.” Rochette is about 455 meters from the first sample site, at the top of a ridge named Citadelle. This outcrop has survived millennia of wind erosion, suggesting that it should withstand Perseverance’s drill more easily.