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Is this the brightest object in the universe?

Also, a bus-sized satellite made an uncontrolled re-entry to Earth

Welcome to your weekly space news from Ad Astra! I’m Swapna Krishna.

This week:

This quasar is the most luminous object we’ve ever seen

Is this quasar the brightest object in the universe?

Credit: ESO/Digitized Sky Survey 2/Dark Energy Survey

Quasars are a kind of active galactic nucleus (AGN). An active galactic nucleus is a supermassive black hole at the center of a galaxy and the luminous accretion disk, made up of gas and dust, surrounding it. Sometimes jets of matter can escape the accretion disk, and we can detect those all along the electromagnetic spectrum.

Hubble looking at AGN Z 229-15, Credit: ESA/Hubble & NASA, A. Barth, R. Mushotzky

While all active galactic nuclei are bright, quasars are some of the most luminous objects in the universe. They’re that bright because of the interaction between the gas and dust in the accretion disk as matter falls into the black hole. This means that quasars emit more light than our entire galaxy combined.

This specific quasar, called J0529-4351, is about 12 billion light years away from us, and scientists studied it using the VLT (Very Large Telescope).

The VLT, Credit: J. Busqué/ESO

The supermassive black hole powering it is absolutely ravenous because that’s how it works — the faster a black hole consumes matter, the more luminous the quasar. This supermassive black hole is eating the mass equivalent of one of our suns per day, which means it’s the fastest growing black hole we’ve ever detected. It’s currently about 17 billion solar masses and growing.

Artist’s conception of quasar J059-4351, Credit: ESO/M. Kornmesser

The accretion disk for the supermassive black hole is seven light years in diameter. Scientists have posited that it might be the largest accretion disk in the universe.

This quasar was actually included in one of Gaia’s datasets. Gaia is a really cool spacecraft from the European Space Agency that is creating a three-dimensional map of our sky.

Credit: ESA/Gaia/DPAC

That’s really the best way to find quasars — looking through data from large swaths of the sky. But because there’s so much data to sort through, scientists often use machine learning to identify potential quasars.

This particular one was actually initially ruled out by the computer because it’s so bright. It classified this quasar as a star much closer to Earth. Scientists observed it last year, and only then did they discover that it was in fact a quasar. In the paper, which was published in Nature Astronomy, the science team points out that there are probably many more quasars hiding in plain sight just like this one.

Hubble spies two galaxies in a cosmic tug of war

Hubble has been doing a series of photos on colliding galaxies, and I’m really intrigued by this latest set — a galaxy that seems to be losing a cosmic game of tug of war.

Credit: NASA, ESA, STScI, Jayanne English (University of Manitoba)

This is the galaxy AM 1054-325, which used to be a spiral galaxy like our own. but it’s been distorted into this “S” shape with this galaxy tail because of the gravitational influence of another galaxy.

Spiral Galaxy NGC 1376, credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

What’s interesting about this is each of these little pearls is actually brand new star formation. It occurs when dense gas and dust is jostled by the gravitational pull of the other galaxy. It collapses and forms these star clusters with about a million new stars per pearl in this string of pearls. These clusters are pretty young in the cosmic sense, just 10 million years old.

It’s not clear what will happen to these stars — will they stay a part of this galaxy, or will they become globular clusters that orbit their host galaxies? (We have globular clusters like that here orbiting the Milky Way). Galaxy mergers and collisions don’t destroy stars or planets — there’s too much empty space. Instead, the interaction of gas and dust usually spurs star and planet formation.

If you want to see more, I have a video on two of Hubble’s other pictures in this series.

IM-1: Update on the moon landing

Credit: Intuitive Machines

I would be remiss if I didn’t mention IM-1, Intuitive Machines’ attempt to land on the moon yesterday, February 22. The landing was successful. The team received a faint signal from Odysseus’s high-gain antenna, and they’ve confirmed the lander is upright. We’re still getting information on this, but it’s good news for sure!

Let’s talk about a mission to retrieve space junk from orbit

Rocket Lab is well known for its Electron rocket, which is almost entirely 3D printed. The company launches small payloads, up to 661 pounds, to low Earth orbit.

On Monday, February 19, Rocket Lab launched an orbital debris inspection satellite. That’s right - it’s a satellite to inspect space junk.

Space junk is becoming a huge problem in orbit. There’s somewhere in the neighborhood of 50,000 objects up there floating in orbit. Around 7,000 of them are active satellites; the rest are pieces of rockets, defunct satellites, and more. It’s getting crowded up there, and I’ve discussed quite a bit about how satellite pollution is affecting ground and space-based astronomy — satellite trails are even affecting Hubble images.

Not only that, but there’s something called Kessler syndrome, which is the scary scenario that one small piece of space junk might collide with another and another, and in a chain reaction, might destroy all the active satellites in low Earth orbit. We don’t want that happening, which means figuring out a way to clean things up is important.

If you’re wondering why these objects don’t just fall back to Earth and burn up, they often do — I’m going to talk about ERS-2, the bus-sized defunct satellite that came crashing back to Earth next. But even the ISS needs regular boosts from visiting spacecraft to stay in orbit. Otherwise its orbit would decay and it would fall back to Earth.

But the ISS is in a very low orbit. In higher orbits, where satellites are traveling relatively fast, the orbital decay is pretty negligible. We can’t really wait for these satellites to come down, and this kind of uncontrolled re-entry can be dangerous.

Illustration of the ADRAS-J satellite in orbit, Credit: Astroscale Japan

That’s where this satellite, which is from the company Astroscale Japan, comes in. This is a partnership with JAXA, the Japanese space agency — much like NASA partnered with the company Intuitive Machines on their lunar lander. The larger aim here is to figure out a way for robotic satellites to approach and retrieve large pieces of space junk from orbit.

This satellite, called ADRAS-J, is the first step. It’s designed to test technology to approach and rendezvous with large pieces of space junk. We have a lot of experience with rendezvous in orbit—the ISS does it all the time.

But that’s with two spacecraft that are designed for this purpose. Orbital space junk isn’t, which is why this mission will only fly around the second stage of a Japanese H2-A rocket that launched in 2009. It will take pictures and study the debris for three to six months.

Astroscale reported that on February 22, the ADRAS-J satellite successfully began rendezvous operations as it moves to the orbit of the HII-A rocket stage.

Japan’s H2-A rocket, credit: JAXA

It’s a big challenge - they don’t know the condition of the stage, it can’t be communicated with, it doesn’t transmit GPS data so we don’t know where exactly it is, and there’s no way to control the rocket stage. I’m really looking forward to seeing what happens here and I’ll continue with updates as I have them.

A bus-sized satellite made an uncontrolled re-entry to Earth

Speaking of space junk, you may have seen headlines about ERS-2, the bus-sized satellite that came careening back to Earth this week.

ERS-2, Credit: ESA

The 5,000-lb satellite was launched by the European Space Agency in 1995, and at the time it was a sophisticated Earth-observation satellite. But after its mission ended, it became just another piece of space junk.

The ESA has been slowly de-orbiting this satellite since 2011. After 66 maneuvers to gently guide the spacecraft back into Earth’s atmosphere, the defunct satellite finally hit 80 km above the Earth’s surface. This is where the pull of the Earth is strong enough that a piece of space junk will start breaking apart.

The actual re-entry was uncontrolled, or you can use the nicer term, a “natural reentry”. (To be clear, I don’t prefer this term.) The European Space Agency used up all of the remaining propellant on the spacecraft to get it to a point where it would break apart in the atmosphere. Once it started on its fiery journey towards Earth, there was nothing to do but watch it burn as it re-entered over the Pacific Ocean.

The satellite imaging company HEO actually caught pictures of the satellite on the way down….and it looks awfully familiar, like something from a galaxy far far away.

Credit: HEO

NASA is hiring Martians; are you up for the job?

NASA put out an interesting job ad this week — they’re looking for Martians.

The job is for a year-long simulation of a Mars mission starting in the spring of 2025; it’s the second of three missions that’s part of CHAPEA, or Crew Health and Performance Exploration Analog.

Growing crops on “Mars,” credit: NASA/CHAPEA team

You’d be a part of a four-person crew living and working inside a 1,700 square foot space called Mars Dune Alpha, located at NASA’s Johnson Space Center in Houston, TX. You’d basically be simulating all aspects of a Mars mission — according to NASA, that includes “resource limitations, equipment failures, communication delays, and other environmental stressors.”

A “Marswalk” performed by the first CHAPEA mission, Credit: NASA/Chapea crew

The first mission is underway right now. The crew has grown crops, made simulated space walks (the 1,700 square feet includes an outdoor area that simulates Mars’s environment), and performed other activities to help NASA understand what astronauts might go through when living and working on another planet, far from the help and resources of Earth.

The habitat under construction, credit: NASA

It’s certainly an interesting job. If you’re interested, and between the ages of 30-55, a U.S. citizen or permanent resident, and an English speaker, you can apply at NASA’s website.

Japan successfully launched its H3 rocket

In rocket news, there are a few interesting things going on.

Credit: JAXA

Japan successfully launched the H3 rocket this past Saturday. This is their new flagship rocket, and this second attempt successfully reached orbit. Their first attempt, which was almost a year ago, lifted off the ground but the second stage of the rocket failed to ignite.

It’s great news for Japan, which has been trying to become more of a presence in spaceflight over the past few years. The question is whether this rocket will be able to complete with SpaceX’s Falcon 9, as well as other rockets like ULA’s new Vulcan and the upcoming Ariane 6 from the ESA.

Blue Origin’s New Glenn is vertical on the launch pad!

Blue Origin also had rocket news this week. The New Glenn rocket is vertical on the launch pad.

Credit: Blue Origin

The rocket was rolled out to Launch Complex 36 at Cape Canaveral, FL. There’s no launch on the schedule, this is just for testing — the integrated tanking test specifically, in which they’ll fill the first stage with propellant (liquid nitrogen specifically, for this test, though the rocket will use liquid oxygen and natural gas). The rocket doesn’t currently have engines installed; they’ll be installed after the test. A hotfire test — when they’ll finally fire the engines — could happen this summer, and then the vehicle will FINALLY be ready for launch.

It’s worth noting that New Glenn is a heavy lift rocket, like SpaceX’s Falcon Heavy, so it will be able to deliver larger payloads to orbit.

And I believe that is all the space news I have for you this week!