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- We found a black hole in our galactic neighborhood
We found a black hole in our galactic neighborhood
Also, NASA confirms that space junk was from the ISS
This week's space news:
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What’s going on with Mars Sample Return?
If you’re curious about NASA’s wild announcement this week about returning samples from the red planet, a mission called Mars Sample Return, I had so much to say about that I have an entire separate post on it — so check that out if you’re so inclined. It’s certainly a strange story, and there’s a lot to dive into there.
Yes, that space junk was from the ISS
In other weird news, remember that space junk story I talked about a couple of weeks ago, where part of a battery pallet jettisoned from the ISS may have hit a Florida home? Well, NASA confirmed this week that the debris was basically from support equipment that was used to secure the battery to the pallet (not the battery itself, as some of us thought.)
NASA’s photo of the ISS debris, credit: NASA
NASA did release the first part of its new space sustainability strategy last week, which has nothing to do with this particular situation, but is a good acknowledgement that space junk is a huge problem. It basically lays out the goals in order to develop a framework for confronting this increasingly important issue,
They also put out a cost-benefit analysis in March about remediation of debris on orbit — that is, reducing or removing space junk that is cluttering up low-Earth orbit. The conclusions it comes to are that it’s financially worth cleaning up small debris in orbit.
It’s good that they’re really paying attention to the issue, but the report definitely has some issues. As Dr. Sam Lawler, who is an expert on satellite pollution and space junk, told me:
“This is a good step in the right direction . . . but it doesn’t go nearly far enough.”
She points out that their satellite collision model, which looks at the potential of satellites to collide with debris, only uses U.S. satellites.
Additionally, the information is at times out of date and others wrong (the numbers being used generally are from a couple of years ago, and they only have SpaceX’s Starlink at 1,815 satellites — she points out they currently have 5,809 satellites in orbit with permission to launch and operate 42,000).
Starlink satellites photobombing my Iceland photos
While the report models collisions of debris with satellites, they don’t address satellites colliding with other satellites, which is becoming a bigger and bigger problem.
Additionally, she points out the report doesn’t talk about what happens after these collisions — the creation of additional debris. Remember the Russian ASAT test in 2021? Russia conducted an anti-satellite missile test against a satellite in space. It created more than 1,500 large pieces of trackable debris and possibly hundreds of thousands of smaller pieces. The debris from this test even threatened the ISS, which had to undertake an avoidance maneuver because of a possible collision. Secondary debris from a collision is a huge problem that this report doesn't really address.
The bottom line is that it’s a good start, but it’s not a forward looking analysis, and there are other considerations when it comes to space debris and junk other than just the financial analysis.
Gaia found its third stellar mass black hole
But let’s talk about this black hole. Scientists using the ESA’s Gaia spacecraft data found a new stellar-mass black hole less than 2,000 light years away. This is quite the feat because it’s a dormant black hole which are exceptionally hard to find — we can’t directly observe black holes, and when one isn’t actively consuming matter, they’re just dark and silent.
Credit: ESA
Scientists generally divide black holes into a few categories, but we’re going to focus on one specifically. We all know about supermassive black holes, like the one at the center of our galaxy, are the ones that we talk about the most. These have masses in the hundreds of thousands to billions that of our sun.
But here we’re talking about stellar-mass black holes. When a star the size of our sun collapses, it becomes a white dwarf.
A white dwarf is at the center of the Ring Nebula, credit: NASA/ESA/STScI
When a star eight times the mass of our sun collapses, it goes supernova.
Cassiopeia A supernova remnant, credit: NASA/ESA/STScI
If it’s between 8 and 19 times the mass of our sun, what’s left becomes a neutron star. If it’s 20 times or more times the mass of our sun, what’s left becomes a stellar-mass sized black hole.
Stellar mass sized black holes can grow by consuming matter and colliding with other stars and black holes, but they are generally a few times the mass of our sun to a few hundred times the mass of our sun. The thing is, though, they’re hard to find because unless they’re interacting with something else, they’re just quiet out there in space.
The black hole at the center of our galaxy, credit: Event Horizon Telescope team
Black holes kind of have a bad reputation — people think of them as all consuming monsters, but just talking as an example, I’m not saying this could actually happen — but if a black hole that was the mass of our sun replaced our sun — I mean sure, we’d die because we didn’t have the light of our sun anymore, but the orientation of our solar system wouldn’t change. A black hole affects the matter around it based on its mass, just like a star or anything else. If matter it outside that area, then it’s not going to start sucking it all of a sudden.
We’ve only detected about 50 stellar-mass black holes in our galaxy, but scientists think there could be as many as 100 million. And now, scientists using ESA’s Gaia telescope (which is making a 3D map of the Milky Way) have found a stellar-mass black hole that’s 33 times the mass of our sun.
Gaia’s map of the Milky Way, credit: ESA
In the constellation Aquila, scientists noticed a wobble in a star’s path. They analyzed the wobble to try and figure out what was going on — and the readings matched a stellar mass black hole. This is the third stellar mass black hole we’ve found with Gaia, and it gives us the clearest direct evidence that these black holes aren’t theoretical and do exist.
NASA is sending a dual quadcopter to Saturn’s moon
In other good news, NASA has confirmed the Dragonfly mission, which is a robotic mission to study Saturn’s moon Titan. The mission was on hold pending budget, but now the confirmation has come through with a cost of $3.35 billion and a launch date of July 2028.
Saturn’s moon Titan Credit: NASA/JPL-Caltech/Univ. Arizona/Univ. Idaho
This is a cool mission for a bunch of reasons — we think Titan has a water-ice crust with a salty ocean underneath. It has rivers, lakes, and seas of liquid ethane and methane, and even sand dunes. It’s a very cool and interesting world that deserves a closer look, and now it’s going to get one.
Dragonfly is a dual-quadcopter that will travel across the planet’s surface in hops, traveling much further than a rover could from its landing site to explore the planet on its two-year mission.
Artist’s impression of Dragonfly, credit: NASA
Launch news: Boeing Starliner and Rocket Lab
I also have a few pieces of launch news. First, Boeing Starliner has been rolled out to the launch pad. This will be the first crewed test flight for Starliner, taking two astronauts to the ISS for a week, and it’s currently scheduled for May 6.
Additionally, Rocket Lab, the small rocket launch company with a mostly 3D printed rocket, will launch a demonstration of NASA’s solar sail technology, currently scheduled for Wednesday, April 24 in New Zealand (which would be Tuesday April 23 in the U.S.) The rocket will deploy a CubeSat, which is a small satellite about the size of a microwave, in Earth orbit. After a two-month period of checking out its systems, the satellite will deploy its solar sail to test propulsion based on just the pressure of sunlight acting on the sail in space.