Space News & Blog Articles

At their South Texas Launch Facility, just outside of the village of Boca Chica, SpaceX is gearing up to test the Super Heavy, the booster element of their Starship launch system. This massive reusable first stage rocket will be responsible for sending the Starship orbital vehicle to space, where it will deliver satellites to orbit, payloads and people to the Moon, and (if all goes as planned) the first human settlers to Mars.

According to a recent statement issued by SpaceX founder Musk Musk, the Starship could also be used to “chomp up debris” in Earth orbit. As usual, the statement was issued via Twitter, where Musk was once again addressing questions posted by followers and fans. The topic arose after Musk shared the latest updates about Starlink, one of a handful of satellite constellations that are bringing broadband internet services to every corner of the planet.

Specifically, Musk was sharing the latest artwork that will adorn the Starlink satellite covers, the visor-like appendages that make Starlink satellites less visible in orbit. Henceforth, these covers will feature a diagram of a transfer orbit from Earth to Mars, a clear reference to Musk’s long-term vision of colonizing the Red Planet. This is not unlike the terms of service for Starlink’s public beta test back in Nov. 2020, where participants had to acknowledge Mars as a “free planet.”

In any case, a user who goes by the Twitter handle Hide yo memes (@REQNews) asked if SpaceX had any other mitigation measures in mind to reduce the problem of space debris. Specifically, the user referenced the Kessler Syndrome (named for NASA space debris expert Don Kessler) which states that once orbital debris reaches a certain critical mass, it will create a chain reaction of collisions and more debris.

According to their initial FCC filing (issued in Nov. of 2016), SpaceX requested a license to operate a constellation of 4425 non-geostationary satellites (NGS) in orbits of between 1100 and 1300 km (680 and 800 mi). By Nov. of 2018, SpaceX announced that they were adjusting this plan and now wanted to send their first 1600 satellites to an altitude of 550 km (350 mi), where they would deorbit and burn up in the atmosphere sooner.

A team of astronomers has found that giant, organized magnetic fields can help drive some of the most powerful explosions in the universe. But when all is said and done, the shock wave from that blast scrambles any magnetic fields in a matter of minutes.

Some gamma-ray bursts (GRBs) occur when giant stars die. Their cores fold in on themselves, collapsing to form a black hole. Soon after it forms, material from the surrounding star falls inwards. There, the intense energies drive the creation of huge, powerful, structured magnetic fields. Those magnetic fields whip some of the in-falling material around the black hole and out along two long, thin jets. When viewed from Earth, its these jets that give this event its characteristic flash of high-energy gamma ray radiation.

But the story doesn’t end there. The remainder of the star continues exploding, sending out a shock wave. That shock wave quickly destroys the magnetic field, leaving only tangled wreckage in its wake.

At least, that’s the theory. But demonstrating the correctness of that theory has been a challenge, because astronomers have to measure the magnetic fields soon after the gamma ray burst event.

So a team of astronomers did just that, announcing their results in a recent paper.

Space may be pretty, but it’s dangerous. Astronauts face a much higher dose of ionizing radiation than us Earth-bound folks, and a new report says that NASA’s current guidelines and risk assessment methods are in serious need of an update.

On the surface of the Earth, protected by our extensive magnetic field and layers of thick atmosphere, we experience about 2-3 milliSieverts (mSv) of radiation exposure every year. Even that background level is enough to trigger the occasional cancer growth.

But astronauts, especially those hoping to go on upcoming long-term missions to the Moon and Mars, face a much greater risk due to the high-energy, ionizing radiation constantly soaking every cubic centimeter of space. To mitigate that risk, NASA currently implements a system based on “risk of exposure-induced death” (REID). The space agency estimates the exposure for each astronaut based on their sex, and if the REID exceeds 3%, their spacefaring careers are over.

However, a new report issued by the National Academies of Sciences, Engineering, and Medicine recommends that NASA update its guidelines. Instead, NASA should implement a single, uniform limit of 600 mSv, which would represent a 3% REID for a 35 year old female astronaut (considered the most suspectible group).

“NASA should continuously strive to base its standards on the best available science as it embarks on this new phase of space travel and exploration,” said Hedvig Hricak, chair of the department of radiology at Memorial Sloan Kettering Cancer Center, and chair of the committee that wrote the report. “As science on radiation-related cancer risks is constantly evolving, NASA has an important opportunity to revisit its space radiation health standard. We hope this report will guide NASA in protecting the health of astronauts throughout their careers.”

Planetary formation theory has been undergoing a lot of changes recently, with an ever expanding litany of events that can potentially impact it.  Everything from gravity to magnetic fields seems to impact this complex process.  Now scientists want to add another confounding factor – massive solar flares thousands of times more powerful than the most powerful we have ever observed from the Sun.

That most powerful flare, known as the Carrington Event, was still strong enough to damage the Earth’s atmosphere, and likely would have done significant damage to the world’s electrical grid, if it hadn’t happened in 1859.  But the kind of flares that Dr. Kostantin Getman of Penn State University and his colleagues found, while looking at young stars with the Chandra X-Ray Observatory, packed at least 100,000 times more energy than the Carrington Event.

The researchers found these powerful flares in 40 different star forming regions throughout the galaxy, observing a total of 24,000 stars.  Amazingly, all 40 regions had these events happening in them.  Incredibly powerful solar flares affect stars with different masses, and at different stages of evolution, such as when they are simply surrounded by dust or when they have planets formed already.  One important detail is that all of the stars in the study average to be about 5 million years old – relatively young compared to our sun at 4.5 billion years.  Another is the fact that the regular “super-flares” that had the power of 100,000 times a Carrington Event occurred multiple times per week on average in young stars, while more powerful megaflares, with at least 10 million times the energy of the Carrington Event, occurred around twice per year.

There were some similarities though.  Dr. Getman and his colleagues modeled some 55 of the flares in detail to see how they compared to the more familiar, tame version from our own sun.  They found loops of magnetic fields caused by the flares were anchored in the star itself, rather than connected between the star and its protoplanetary disk, similar to how coronal mass ejections work.

Despite their similarities, that much activity that consistently is sure to have an impact on its surroundings.  Many scientists had previously suggested that solar flare might help with the early stages of the planetary formation process – blowing away dust while causing rocks to meld together in pebbles, whose increased gravity then attracts other material.  While this is still plausible, it is likely only one component of a much more complex story of planetary formation, which scientists are still learning more about.

About 97% of all stars in our Universe are destined to end their lives as white dwarf stars, which represents the final stage in their evolution. Like neutron stars, white dwarfs form after stars have exhausted their nuclear fuel and undergo gravitational collapse, shedding their outer layers to become super-compact stellar remnants. This will be the fate of our Sun billions of years from now, which will swell up to become a red giant before losing its outer layers.

Unlike neutron stars, which result from more massive stars, white dwarfs were once about eight times the mass of our Sun or lighter. For scientists, the density and gravitational force of these objects is an opportunity to study the laws of physics under some of the most extreme conditions imaginable. According to new research led by researchers from Caltech, one such object has been found that is both the smallest and most massive white dwarf ever seen.

The study that describes the research team’s findings appeared in the July 1st issue of the scientific journal Nature. The research was led by Ilaria Caiazzo, the Sherman Fairchild Postdoctoral Scholar Research Associate in Theoretical Astrophysics at Caltech, and included colleagues from Caltech, the University of British Columbia (UBC), UC Santa Cruz, and the Weizmann Institute of Science in Rehovot, Israel.

Artist’s impression of white dwarf ZTF J1901+1458 above the Moon in this artistic representation; in reality, the white dwarf lies 130 light-years away in the constellation of Aquila. Credit: Giuseppe Parisi

This white dwarf, known as ZTF J190132.9+145808.7 (aka. ZTF J1901+1458), is located about 130 light-years from Earth and is estimated to be 1.35 times as massive as our Sun. However, this white dwarf has a stellar radius of about 1810 km (1,125 mi) – slightly larger than the Moon (1,737.4 km; 1,080 mi) – which makes it the smallest and most massive white dwarf ever observed. As Caiazzo explained in a recent press statement from the W.M Keck Observatory:

It’s tough to see inside of Saturn, because the atmosphere is opaque to all wavelengths of radiation. We have to rely on computer simulations and physics-based guesswork to try to understand the interior of that giant world. But researchers are becoming more adept at a different technique: looking for the slightest motions in the rings of Saturn.

The rings of Saturn are made of trillions of small bits of water ice, most small enough to fit in your hand. Each individual bit orbits Saturn in its own way, and each one is a tiny gravitational detector.

The planet Saturn isn’t just a simple, uniform ball of gas. It has complex layers and perhaps even a rocky core. Material moves up and down within the Saturnian atmosphere, and everything is in a constant state of motion.

Every time the interior of Saturn shifts, the particles of ice that make of the rings respond, affected by the new distribution of gravity. And different internal compositions of Saturn will make themselves known in the rings, because different arrangements of material will lead to different preferred orbits for ring material.

Sometimes entire waves can spread out inside the rings, or brief ripples appear in them. The analysis of the rings depends on having excellent observations of them, which we have thanks to NASA’s historic Cassini mission. That mission took countless high-resolution pictures of the rings, which astronomers can now use to try to reconstruct the interior of Saturn.

If it were’t for an enormous halo of dark matter enveloping our galaxy, the spin-rate of our central bar should stay pretty constant. But researchers have recently inferred that it has slowed down by almost 25% since its formation, a clear sign of the presence of dark matter.

How do you measure the spin-rate of something that takes millions of years to make a single revolution?

The answer is chemistry. Stellar chemistry.

Stars near the center of the galaxy are much richer in “metals”, which is the word astronomers use to denote any element heavier than helium. Stars in the outskirts, however, are much more lacking in metals. Therefor, if you happen to come across a group of stars that is exceptionally rich in metals, then it most likely wandered away from the center of the galaxy.

That’s the case for the Hercules stream, a large group of stars observed with the Gaia satellite. The Hercules stream is a metal-rich clump of stars, but sits relatively far from the galactic center. There’s something else intriguing about the Hercules steam: it’s locked in a gravitational dance with the central bar of the Milky Way.

Planets move in mysterious ways.  Or at least their surfaces do.  Earth famously has a system of tectonic plates that drives the movement of its crust.  Those plate tectonics are ultimately driven by the flow of material in the mantle – the layer directly below the crust.  Now, scientists have found a slightly different deformation mechanic on our nearest sister planet – Venus.

The research, carried out by Dr. Paul Byrne of North Carolina State University and his colleagues, used data from NASA’s Magellan spacecraft which visited Venus back in the 90s.  While orbiting the planet, the probe collected a radar map of its surface, which is obscured by a thick atmosphere at wavelengths visible to the human eye.

One of the most famous pictures generated from Magellan’s trip to Venus was this one of Maat Mons. This NASA Magellan image was released on April 22, 1992.
Credit – NASA

In part of that radar map, the researchers noticed something interesting – a series of blocks where the crust of the planet (known as the “lithosphere”) looked like it had moved.  This finding flew in the face of the convention wisdom of Venus, which held that Venus’ lithosphere was immobile.  

As any good scientist knows, if the data disproves an old theory, a new theory is required.  So the team set out modeling the deformation to see if they could figure out what might have caused it.  The answer appears to be that he deformation is caused by the slow movement of the planet’s interior.  

Early this morning, Sir Richard Branson and Virgin Galactic achieved a major milestone in the development of commercial space travel. Along with a team of specialists, Branson traveled to the edge of space aboard the VSS Unity and made it safely back to Earth. In so doing, Branson and his company have also fired the latest salvo in the ongoing race between the titans of the commercial space industry (aka. NewSpace).

Coverage began at 7:30 am PST (10:30 am EST) and was live-streamed on the company website, its Youtube channel, and social media accounts. As promised, the event was hosted by comedian Stephen Colbert and co-hosted by a panel that consisted of famed former astronaut and science communicator Chris Hadfield, industry professional and popular science communicator Kelly Jerardi, and Virgin Galactic structures engineer Veronika McGowan.

Kicking things off in style, Branson rode his bicycle to Spaceport America and joined the rest of the crew, who then entered the facility and signed the “astronaut log book.” This included aerospace engineer Beth Moses (Astronaut 002), Virgin Galactic’s Chief Astronaut Instructor; Colin Bennett (Astronaut 003), the company’s lead operations engineer; and Sirisha Bandla (Astronaut 004), Virgin Galactic’s vice president of government affairs and research.

At 08:21 AM PDT (11:21 AM EDT), the mission took off with its carrier – the VMS Eve (named after Branson’s late mother) – and was flown to its launch altitude of over 13,715 m (45,000 ft). At 09:15 AM PDT (12:15 PM EDT), the VSS Unity detached from VMS Eve and engaged its rocket motor for a full burn of 60 seconds. At this point, Branson and his fellow crewmembers were given the green light to undo their safety harnesses and float around the cabin.

The spacecraft achieved a top velocity of Mach 3 (3,700 km/h; 2,300 mph) and reach an altitude of 86 km (53.5 mi) – just slightly below the Kármán Line (the official boundary of space). The entire flight was captured by flight cameras mounted on the mothership, the spacecraft, and the chase plane. Branson and crew also live-tweeted the event and shared photos of their ascent and the four minutes of weightlessness they experienced.

Magnetic fields are great for lots of things – directing explorers, levitating trains, and containing nuclear fusion reactions are just an example of what these invisible forces can do.  Now we can ascribe another feature to magnetic fields – they can give planets a rocky core.

That is the result from research done by Dr. William McDonough at the University of Maryland and Dr. Takashi Yoshizaki from Tohoku University.  The pair developed a model that was published in Progress in Earth and Planetary Sciences that show how the sun’s magnetic field controlled the gradient of raw materials that the planets were formed out of. 

One of the outcomes of their research was a correlation between a newly formed planet’s “density and proportion of iron” and the strength of the star’s magnetic field during that planet’s formation.  Though without experimental controls the research is unable to show causation, it makes logical sense that iron, which is magnetic, would be affected by the massive magnetic fields emitted by a young star.  

Our own solar system is a reasonable example of this – Mercury, despite being the smallest planet, has an iron core that makes up ¾ of its mass.  As planets get farther and farther away, their metallic cores make up less and less of their overall weight, with Venus and Earth coming in at about ? of their weight in their cores while Mars clocks in at ¼.

The cores themselves aren’t created by magnetic fields though.  Magnetism’s impact is more subtle, drawing chunks of iron together into newly formed protoplanetary balls.  Gravitational forces then take over in driving the dense iron into the core of the planet, where it either melted or cooled, depending on a variety of other planetary formation factors. U

It’s no secret that the commercial space industry (aka. NewSpace) has become immensely lucrative in recent years, nor the fact that it has become intensely competitive as a result. To illustrate, one needs to look no further than the top three NewSpace companies in the world right now: SpaceX, Blue Origin, and Virgin Galactic. Between these three companies, all founded by billionaires with similar visions, a new space race has begun.

In recent months, the race has intensified as Jeff Bezos announced that he would be going to space on the inaugural flight of the New Shepard rocket. In response, Virgin Galactic founder and CEO Richard Branson announced earlier this week that he would fly aboard the VSS Unity as it makes its latest test flight. If successful, this mission – scheduled for Sunday, July 11th (weather permitting) – will see Branson become the first billionaire to go to space.

In the past, Branson has said that he would fly aboard his spacecraft once the company began conducting crewed flights. Until recently, company spokespersons stated Branson’s flight would take place later this year after another crewed test flight took place. But when Bezos announced his plans early last month, there were rumblings that Branson was thinking about expediting the timetable.

According to their latest updates, Virgin Galactic plans to launch the “Unity 22” mission on Sunday, July 11th, in the early morning hours. The spacecraft will take off with its carrier aircraft (WhiteKnightTwo) from Spaceport America in the Jornada del Muerto desert basin of New Mexico. This event will also be shared via a global livestream, which can be watched on Virgin Galactic.com and the company’s Twitter, YouTube, and Facebook channels.

Famed comedian Stephen Colbert, who has interviewed Branson several times on his late-night shows, has been confirmed as the host. The event will also feature the Grammy-nominated singer Khalid, who will be debuting a new song of hers at the landing site after the test flight is complete. According to Virgin Galactic’s official press release, the purpose of flight will be threefold:

Predicting volcanic eruptions is notoriously tricky. In large part this is because volcanos are unique, each with their own quirks and personalities: the lessons learned from studying one volcano may not apply directly to another. Luckily, researchers are getting better at finding warning signs that they can apply broadly. Some of the most well-known are heightened seismic activity, rising temperatures, expanding magma pools, and the release of gases. New research using satellite imagery now offers a new warning sign for underwater volcanos: a change in the color of the ocean.

The idea is simple: it has long been known that as underwater volcanos prepare to erupt, the gases and compounds they release affect the composition of the surrounding seawater. Iron-rich water looks yellowish or brown, for example, while aluminum and silicon turn the water white. The challenge has always been in systematically applying this information to make useful predictions. Measuring these color changes accurately isn’t easy.

Yuji Sakuno, associate professor at Hiroshima University, has been working on this problem. As an expert in remote sensing, his key tool in this endeavor is the Japanese Space Agency (JAXA)’s Global Change Observation Mission – Climate (GCOM-C) satellite. GCOM-C observes the ocean every 2-3 days at 250-meter resolution, giving Sakuno reliable data about changes in water color over time.

By combining GCOM-C imagery with eruption information from Himawari-8 (a geostationary weather satellite) Sakuno was able to note changes in sea water colour about a month prior to volcanic activity on Nishinoshima Island.

One of the breakthroughs that made this possible involved finding a way to measure color accurately, despite the way that sunlight can distort and play tricks with apparent water color. Sakuno looked to other areas of research to find a solution: previous work done on hot spring water provided the tools needed to counteract the Sun’s distortions.

These days it seems you can’t walk through a bookstore without bumping into a book or magazine pointing out the negative consequences of climate change.  Everything from the hottest years on record to ruining astronomy can be tied to climate change.  Now some new science lays another potential problem at climate change’s feet – the Earth is retaining more than twice as much heat annually as it was 15 years ago.

A team from NASA and NOAA found that the Earth’s “energy imbalance” doubled between 2005 and 2019.  The energy imbalance is simple to understand but complex in its causes and impacts.  It is the difference between the amount of energy absorbed by the Earth and the amount of energy emitted by it.  Any increase in the energy imbalance means the overall Earth system is gaining energy, causing it to heat up.

To quantify this change, the team used data from two separate sources – NASA’s Clouds and the Earth’s Radiant Energy System (CERES) and a system run by NOAA called Argo.  CERES specializes in how much energy is entering and leaving the Earth.  Most of the energy entering s in the form of solar radiation, while energy leaving the system could take a variety of forms, including some of that solar radiation bouncing off of white clouds.

Argo, on the other hand, estimates the rate of temperature increase for the oceans. 90% of the energy that is absorbed by the Earth system is absorbed into the oceans, so any significant energy imbalance would be seen as a heating up of the oceans.  

Data from both sensing platforms pointed to the same conclusions – that the Earth was absorbing more energy than it was emitting, that energy is then stored by the ocean, and the annual amount of energy stored has increased dramatically in the recent past.  All of these findings have important implications for the future of understanding and coping with climate change.

Every day, there are more indications that show how anthropogenic factors are causing uncomfortable changes in our climate. Here in beautiful British Columbia, this means that wildfires are once again threatening countless acres of forests, communities, and wildlife. By the end of June 2021, more than 40 wildfires were raging across the province, including a rather substantial cluster around the town of Lytton.

Located just 150 km (about 93 mi) northeast of the city of Vancouver, Lytton, had to be evacuated on June 30th after an extreme heatwave led to wildfire sweeping through the area. These wildfires and the impact they were having at the time was being monitored by some of NASA’s Earth Observatory satellites. In a series of images recently shared on their website, they show the fires that were raging near Lytton just hours before the evacuation.

The satellites included the NOAA-20 satellite, which was launched as part of the Joint Polar Satellite System (JPSS) program mounted by NASA and the National Oceanic and Atmospheric Administration (NOAA). Using its Visible Infrared Imaging Radiometer Suite (VIIRS), the NOAA-20 acquired an image (shown below) of three fires that were burning around Lytoon at the time – 02:00 PM PDT (05:00 PM EDT) on June 30th.

These include the McKay Creek fire (left) and the Sparks Lake fire (right) that burned an estimated 150 – 200 km (60 – 75 mi) about 25 km (15.5 mi) north of Lillooett and 45 km (28 mi) northeast of Kamloops. The image also shows a smaller fire burning just 5 km (3 mi) south of Lytton, located in the vicinity of George Road. The images also show the different types of clouds that accompany these sorts of wildfires that occur in wooded areas.

The second image (shown below) was acquired by the Operational Land Imager (OLI) on the Landsat 8 satellite, which was developed jointly by NASA and the U.S. Geological Survey (USGS). This image was taken at 12:00 PM PDT (03:00 PM EDT) and provides a more detailed look at the McKay Creek Fire and the contrast between pyroCbs clouds and dry smoke, as well as the fires driving them.

Surprising findings sometimes come in small packages.  And sometimes those small packages have to be delivered by very big systems.  Physicists at MIT made some surprising findings from a very small radioactive molecule that was created in an accelerator at CERN.  They believe that, if studied closely enough, these new types of radioactive molecules could shine some light on why there is more matter than anti-matter in the universe.

Radioactive molecules might seem a strange place to start looking for the answer to one of the fundamental questions that has stumped modern day physics.  But these aren’t your everyday radioactive molecules – they usually only exist in neutron star mergers or supernovae.  In fact, this is the first time they have been created synthetically.

What makes them interesting is their number of neutrons.  Neutrons usually don’t have much of an effect on a molecule, being one millionth the size of the molecule it is a part of.  But the physicists were able to measure the impact of the neutron on its molecule’s energy.  That in itself is a breakthrough, but it was by no means an easy road to get there.

First, the researchers, led by assistant professor Ronald Fernando Garcia Ruiz of MIT, had to create the novel molecule.  They were particularly interested in radium monoflouride (RaF), an unstable radioactive molecule that only exists for a few seconds after it’s created.   After successfully creating some for the first time last year, they turned their attention to different isotopes of this unstable molecule.  

The isotopes in question contained different numbers of neutrons.  To create these different isotopes, the researchers developed a disc made up of uranium-carbide and injected carbon fluoride gas.  After zapping it with a low-energy proton beam at CERN, the researchers released a veritable zoo of new molecules, including 5 different isotopes of RaF.  

This month, two billionaires will be flying to space aboard their very own commercial launch vehicles. The first to go will be Amazon founder Jeff Bezos, who will be a passenger aboard the inaugural crewed flight of the New Shepard on July 20th. Mark Bezos, Jeff’s brother, will be accompanying him on this flight, as will the person who won the auction that wrapped up on June 12th (they bid $28 million for the seat).

On July 1st, Blue Origin announced that the fourth passenger on this historic flight would be Wally Funk, a pioneer in aerospace who trained to become an astronaut back in the 1960s. As part of the “Mercury 13” Woman in Space Program, Funk was one of several qualified test pilots and graduated at the top of her class. And now, sixty years later, she is once again a pioneer since she is the oldest person that has ever flown to space.

The announcement was made in a video shared via Blue Origin’s website and Jeff Bezos’ Instagram account. In it, Funk relates how she has been flying all of her life, and how the opportunity to go to space after all this time will be “the best thing that ever happened” to her. We also see Bezos describing what the flight will entail, particularly the four minutes of weightlessness they’ll experience after the crew capsule separates from the first stage launcher.

“In 1961, Wally Funk was at the top of her class as part of the “Mercury 13” Woman in Space Program,” said Bezos in a written statement accompanying the video. “Despite completing their training, the program was canceled, and none of the thirteen flew. It’s time. Welcome to the crew, Wally. We’re excited to have you fly with us on July 20th as our honored guest.”

The Mercury 13 program (1960-1961) saw 13 female pilots go through the same medical tests and training as the male astronauts selected for NASA’s Mercury program. These women were all experienced pilots who did better than their male counterparts in some aspects of training and (in some cases) even had more flying time. Funk was at the top of her class and outperformed the male astronauts in every category, but never got to go to space. As she related in the video:

Spacewalks are a relatively rare occurrence, and they normally draw at least a moderate amount of media coverage.  So when a team of Chinese astronauts performed a spacewalk outside of their newly launched space station for the first time, it was bound to attract some notice.  The successful walk installed equipment, including cameras, outside of the new Tiangong (“Heavenly Palace”) station.

Having reached the space station on June 17th, a crew of three astronauts have set about making their new home fully functional, as they will be staying there for three months.  Two astronauts participated in the walk – Liu Bomin and Tang Hongbo, while a third, Nie Haisheng, remained inside the space station while his colleagues braved the vacuum of space.

The action was captured by a camera that was installed on the station, and was released by the state-owned Xinhua news agency.  Videos show Liu attached to a 15 meter (70 ft) robotic arm that held him in place while he performed installation work with a drill and other hand tools.  

This activity was the first EVA for Liu and Tang, though Liu was present in 2008 when Zhai Zhigang made China’s first ever spacewalk.  All three men on the mission are military pilots, as were NASA’s original astronauts.  

Though this first one was a step in the right direction, many more EVAs will be necessary to fully complete the station.  In fact, the astronauts already on board have even more EVAs planned before they leave. By the end of the year, two more modules will join the Tianhe (“Heavenly Harmony”) module already in place.  Once everything is ready to go, the station can start contributing to the science of microgravity and prolonged space exposure.  It will also provide plenty more firsts for the media to cover.

In the past decade, the discovery of extrasolar planets has accelerated immensely. To date, 4,424 exoplanets have been confirmed in 3,280 star systems, with another 7,453 awaiting confirmation. So far, most of these planets have been gas giants, with about 66% being similar to Jupiter or Neptune, while another 30% have been giant rocky planets (aka. “Super-Earths). Only a small fraction of confirmed exoplanets (less than 4%) have been similar in size to Earth.

However, according to new research by astronomers working at NASA Ames Research Center, it is possible that Earth-sized exoplanets are more common than previously thought. As they indicated in a recent study, there could be twice as many rocky exoplanets in binary systems that are obscured by the glare of their parent stars. These findings could have drastic implications in the search for potentially habitable worlds since roughly half of all stars are binary systems.

For the sake of their study, the research team examined 517 exoplanet-hosting stars that were identified by NASA’s Transiting Exoplanet Survey Satellite (TESS) during its three years in operation. When compared to data from the twin telescopes of the international Gemini Observatory and the WIYN 3.5-meter Telescope at Kitt Peak National Observatory, they found that over 100 of these stars likely had a binary companion.

The paper that describes their findings has been accepted for publication in the Astronomical Journal. Dr. Kathryn Lester, a postdoctoral researcher at NASA Ames Research Center, led the research effort with the assistance of colleagues from NASA Ames, the U.S. Naval Observatory, the NASA Exoplanet Science Institute, the NSF’s National Optical-Infrared Astronomy Research Laboratory (NOIRLab), the Lowell Observatory, as well as Georgia State and Standford University.

The Trouble with Transits

To date, the vast majority of confirmed exoplanets (roughly 75%) have been discovered using the Transit Method (aka. Transit Photometry). This consists of observing stars for periodic dips in their brightness, which can be the result of a planet passing in front of their face (transiting) relative to the observer. Like its predecessor, Kepler, TESS relies on the Transit Method to determine the presence of exoplanet systems around thousands of stars at any given time.

“The best laid plans of mice and men often go awry” – this famous paraphrase of Scottish poet Robert Burns sometimes sums up human ingenuity.  That is exactly what happened when a county in Washington State decided to replace all of its county-owned streetlights with LEDs at least partially in an effort to combat light pollution.  New research shows that they actually made the light pollution worse.

Dr. Li-Wei Hung and her colleagues at the National Park Service recently released a paper currently available on arXiv that details work that they did to monitor the night sky both before and after Chelan County replaced their streetlights with LEDs.

Map of Chelan County and where its street lights are located.
Credit – Hung et al.

Chelan County is located in the north-central part of the state and serves as a gateway to several outdoor recreational areas nearby, including North Cascades National Park.  Given this interest in the outdoors, less light pollution would seem like a benefit to stargazing hoping to catch a glimpse of the Milky Way.

So the county decided to replace all 3,693 of the county-owned streetlights (60% of the total outdoor streetlights in Chelan County) with “full cutoff” light emitting diodes for bulbs.  About 80% of these new LEDs were “3000K” or “warm white light”, while the other 20% were slightly brighter “4000K” bulbs that were installed to meet lighting requirements set by the Washington State Department of Transportation.

Last year we reported on how the Roman Space Telescope’s backers hoped it would be able to detect rogue planets using a technique called “microlensing”.  Now, a team led by Iain McDonald, then at the University of Manchester, beat them to the punch by finding a few examples of Earth-sized rogue planets using data from an already aging space telescope – Kepler.

Both collecting and analyzing the data used in the study wasn’t easy though.  Kepler embarked on a two-month campaign in 2016 that had it looking at millions of stars located near the center of the Milky Way every 30 minutes.  Even with that much data, picking the signal from the noise was difficult.  

They are difficult because microlensing is exhibited by tiny fluctuations in the light of stars when an object passes in front of them.  According to Dr. McDonald, about every one in a million stars in the galaxy is subject to microlensing at any point in time.  So of the million of stars towards the center of the Milky Way, several could be undergoing microlensing right now.

Those events can last anywhere from minutes to days, as it depends on the difference between the foreground object and background stars, as well as the weight of the foreground object.  Of the many microlensing events that take place facing the galactic core, only approximately 1% of them are caused by rogue planets, and the signals from those events are much smaller when compared to microlenses caused by foreground stars.

Despite all the difficulties in collecting data with an old telescope, siphoning through all the additional data and background noise, and trying to differentiate between events caused by stars and those caused by planets, Dr. McDonald and his co-author, Eamonn Kerins were able to find 27 candidates for microlensing events. Of those, four could have potentially been caused by Earth-sized rogue planets.