Weird “old smoker” stars are hiding in the heart of the Milky Way

Welcome to this installment of weekly space news from Ad Astra (formerly Give Me Space)! Let’s talk about what happened this week in space science and spaceflight.

Today I’m going to talk about the latest JWST images, black holes ripping up stars, a gorgeous photo from the International Space Station, moon missions, astronauts assigned to NASA’s Crew-9 mission, and more.

JWST’s PHANGS survey

The biggest news of the week is JWST’s incredible galaxy survey. These nineteen spiral galaxy images are helping scientists understand the ins and outs of galaxy formation, evolution, and structure.

The big deal here, besides how gorgeous they are, is the incredible detail within these images. JWST is able to resolve individual stars in distant galaxies — that’s amazing. NIRCam, or JWST’s near-infrared camera, is what captured the glowing stars. You can see millions of them in these images, while MIRI, the mid-infrared instrument, showcases dust.

In these images, the dust is around and in between the stars. You can peer through the gas and dust, thanks to infrared, and see the red stars, which would be blocked by dust if you were looking at them in visible or UV light. These are the young stars that haven’t yet emerged from their gas and dust shell.

If you want to know more about this survey, check out my video on PHANGS and see the comparison between Hubble’s PHANGS photos and JWST’s.

Astronomers witness 18 black holes ripping up stars

In other cosmic news, astronomers at MIT found eighteen black holes ripping up stars.

When a star is drawn into a black hole, the energy that’s released when the black hole finally rips it apart is called a Tidal Disruption Event. It’s a HUGE burst of energy across the electromagnetic spectrum.

Astronomers have traditionally looked for these events by pinpointing bursts with specific characteristics in the optical and x-ray bands of light. Up to now, scientists have found about a dozen of these, which means this new discovery more than doubles the tidal disruption events we’ve found. Results were published in The Astrophysical Journal.

The way they went about identifying these events is unconventional. Instead of just looking for optical and x-ray bursts, scientists searched for infrared radiation from these tidal disruption events. Infrared radiation is especially prone to occur in so-called “dusty” galaxies. These galaxies have an active galactic nucleus with a supermassive black hole at its center, but there’s a lot of material surrounding this nucleus. That’s in contrast to our own galaxy, where our central black hole Sagittarius A* is relatively dormant because it’s not actively consuming material.

What happens is the tidal disruption event actually heats up the surrounding dust and debris, which gives off infrared radiation. And scientists can look for that, a sharp spike in heat resulting from the tidal disruption event, and find yet more of these. What we’ve found is these events are probably relatively common across the cosmos, and this new method is a reliable way of locating them.

Red giants give off puffs of smoke

In other news this week, scientists found some hidden stars, including stars that randomly emit puffs of smoke.

Scientists call these stars “old smokers” and they’re located near the center of our galaxy. During a 10-year survey of the center of the galaxy, scientists noticed that certain red stars showed strange changes in brightness. It turns out that the team had discovered a new kind of red giant star.

Red giants are dim stars that have moved off the main sequence, meaning they’re nearing the end of their lives. Scientists think that our sun might one day become a red giant. They’re large stars, and relatively cool.

The 21 stars the team found near the heart of our galaxy sit quietly for years, but then every once in awhile, they give out puffs of smoke. The question is why are they doing this?

Scientists aren’t sure yet, but one clue is where the stars are located — they’re in an area of our galaxy called the Nuclear Disk, the innermost part of the Milky Way. The stars in this area tend to be rich in heavy elements. The team thinks that this might make it easier for dust to condense out of gas on the outer layers of a red giant star. How this becomes a puff of smoke, though, is still a mystery.

ISS captured a gorgeous photo of the Earth glowing golden

There’s a gorgeous photo of the Earth, taken from the International Space Station, but the atmosphere is glowing golden. Why is that?

This is called airglow. Around 300 miles above the Earth’s surface (which is right around where Space Station orbits) you can see red, green, purple — or in this case, gold light. This occurs when atoms and molecules high up in Earth’s atmosphere are excited by ultraviolet light from our sun and emit light (called photons) to shed that extra energy. The phenomenon is similar to the Northern Lights, but it’s because of normal radiation not solar wind.

Unlike auroras, it’s really too dim to see from the ground, but the astronauts aboard the International Space Station get a great view of airglow in the ionosphere, which is the Earth’s upper atmosphere.

Elsewhere in the photo, you can see the ISS about 258 miles above the Earth, over the Pacific Ocean. You can see part of the Russian side of Space Station from this photo — a lab module and docking module as well.

NASA named Crew-9 astronauts

NASA named the astronauts for a next crewed mission to the International Space Station! Crew-9 launch of a SpaceX Crew Dragon capsule is scheduled for no earlier than August, and NASA astronauts Commander Zena Cardman, Pilot Nick Hague, and Mission Specialist Stephanie Wilson, and Roscosmos cosmonaut Mission Specialist Aleksandr Gorbunov will be on the flight.

The next NASA mission to the ISS, Crew-8, is currently scheduled for NET February 22 aboard the SpaceX Crew Dragon spacecraft called Endeavour, which will be flying for the fifth time.

Boeing’s long-delayed Starliner is also still on track for an April launch. That will be the first crewed launch of the spacecraft, and will take astronauts Sunita Williams and Butch Wilmore to the ISS for a 10-day stay. We’ll see if that stays on track.

It’s getting crowded up there. The four astronauts from the private Axiom-3 mission are still on the ISS. They launched from Cape Canaveral, FL, on January 18. Undocking for that mission is scheduled for February 3.

This means that there are currently 11 astronauts aboard the ISS (with an additional three Chinese taikonauts aboard Tiangong, making a total of 14 people currently living in space).

Cygnus docked with the ISS

Speaking of the ISS, the private cargo ship Cygnus arrived at Space Station early on February 1. It launched from Cape Canaveral on Tuesday, January 30, so it had about 30 hours in flight before it docked.

The spacecraft was carrying 8,000 pounds of equipment and supplies to the ISS. One of the interesting things on this mission is a metal 3D printer that will test 3D printing small metal parts in space. This is a project from the European Space Agency.

The moon is shrinking

There’s also been some discussion about the moon this week. Headlines that the moon is shrinking were a bit exaggerated — it IS shrinking, but only by about 150 feet over hundreds of millions of years. The real news, though, is that the moon’s changing surface might lead to seismic instability in regions where NASA is looking to land astronauts for Artemis III and beyond.

Basically, as the moon shrinks, it causes moonquakes, landslides, and more. Now, scientists have linked fault lines in the lunar south pole region to the most powerful moonquake seismometers have ever recorded. This could be an issue for NASA’s plans for Artemis III, currently scheduled for no earlier than September 2026, and beyond.

For more on this, check out my video on our shrinking moon.

SLIM update

It’s been an exciting couple of weeks for Japan’s moon lander. SLIM, or Smart Lander for Investigating the Moon successfully made a precision soft landing on the lunar surface on January 20, but in a suboptimal position — its solar cells weren’t receiving power.

See my video on the landing for more information.

However, the rovers were able to deploy (this is a photo of the SLIM lander faceplanted on the moon from its rover LEV-2) and JAXA did get the chance to download landing data from the spacecraft. They did confirm that SLIM made a pinpoint landing, within 55 meters of its landing site.

The reason that the spacecraft didn’t land in an optimal orientation for its solar panels is because about 50 m above the lunar surface, one of the two engines was lost. SLIM was able to compensate for the loss of this engine in real time, but that’s why the actual landing took place a little east of the original target site, because the spacecraft was a little off kilter because it was only using one engine.

The velocity when SLIM landed was 1.4 m/s, which is well within design specifications, and confirms that the spacecraft did soft land successfully. However, because the lateral velocity (how fast it was moving horizontally across the moon’s surface) and attitude were different than expected, the spacecraft settled with the solar cells facing west.

JAXA shut the lander down with 12 percent battery in hopes it would wake up when the solar cells began to charge. Well, that happened this week, and we got some images and more data from SLIM!

That’s the good news. The bad news is now it’s night on the moon, so the cells can’t charge anymore. SLIM is once again shut down, and we’re not sure if it will survive the two-week-long harsh lunar night. It was only designed to operate for one lunar day cycle (also two weeks) so we just have to hope it makes it through the night.

Those are the highlights in what happened in space news this week.

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