Astronomy and Planetary News: Weekend Update Style

by | Feb 24, 2021 | Active Galaxies, Astrobiology, Daily Space, Earth, Mars, Physics, Supermassive Black Holes | 0 comments

IMAGE: An artist’s impression of the Cygnus X-1 system. A stellar-mass black hole orbits with a companion star located 7,200 light years from Earth. CREDIT: International Centre for Radio Astronomy Research.

We’re going to do a rapid-fire rundown of news.

And we’re going to start with the nearby black hole Cygnus X-1. Detected as a powerful source of X-rays in 1964, this compact object, which is located in a binary star system, was the first object assumed to be a black hole. And, until a new paper in Science, we thought it was pretty average, with a twenty-ish solar-mass black hole orbiting next to a large blue giant. The problem is, we may have mis-measured just how far away this system is. 

Research led by James Miller-Jones now shows that Cygnus X-1 is roughly twice as far away as we thought and therefore needs to be a whole lot bigger. Basically, we found out the nearby big monster is actually a farther away, much bigger monster, and we’re no longer sure how it formed. Black holes formed from a single star aren’t supposed to get this big. That said, according to my doctor, I’m also not supposed to get this big. Let’s face it, sometimes mass finds a way and neither I nor the universe like to stay within the limits placed by science.

Black holes come in all sizes and form in a lot of different ways: a single star collapses, one object eats another, smaller black holes merge into bigger black holes, turbulence collapses a lot of stuff in the early universe into a supermassive black hole. There are lots of ways to make black holes. However you make them, once you have that black hole, you have massive gravitational potential, that, just like a bike cruising down a mountain, can accelerate particles to massive energies. 

IMAGE: This image of Centaurus A, an active galactic nucleus ejecting material from its center, combines X-ray, microwave, and visible light images. CREDIT: ESO/WFI (visible); MPIfR/ESO/APEX/A.Weiss et al. (microwave); NASA/CXC/CfA/R.Kraft et al. (X-ray)

Occasionally we find small particles called neutrinos with massive energies, and according to a new paper in The Astrophysical Journal with lead author AV Plavin, these neutrinos probably get generated in the environment of supermassive black holes. These results come from looking at the source of a bunch of high-energy neutrinos — 200 TeV and higher — and saying that they consistently appear to come from a special kind of active galaxy called a blazar.

But again, the universe doesn’t like to stay within limits. Plavin and Company promoted their results on February 22. The exact same day, a different paper came out in Nature Astronomy documenting the story of a 200 TeV neutrino that did not come from a blazar. Nope. It appears to have come from the destruction of a star by a black hole in the outskirts of a distant galaxy. 

In this case, the neutrino was detected as well as the bright flash of light of the star being consumed. Second author Sjoert van Velzen admits: The origin of cosmic high-energy neutrinos is unknown, primarily because they are notoriously hard to pin down. This result would be only the second time high-energy neutrinos have been traced back to their source. 

So yes, in theory, high-energy neutrinos should come from active galaxies, but occasionally, Reality is going to throw us a neutrino from a shredded star as well, because it can.

IMAGE: Ellsworth Mountains, in transit to Subglacial Lake Ellsworth, December 2012. CREDIT: Peter Bucktrout, British Antarctic Survey

Theorists live a hard life. They try and figure out what should be happening, while observational folks are out there actually looking at what is happening. When the theorists get it right, they can get a Nobel Prize, but when they get it wrong, it’s a bad day. 

Enter theorists Louis-Alexandre Couston and Martin Siegert who on February 17 published an article in Science Advances describing how subglacial lakes in the Antarctic could support life. They were cautious, stressing microbial life could exist and explained that: As they have no access to sunlight, microbes in these environments do not gain energy through photosynthesis, but by processing chemicals.

That February 17 paper, well, it was in the works for months, and just two days before it came out, a group of scientists announced how they had quite accidentally discovered not only microbial life, but sea sponges and other weird critters happily proclaiming, “Why yes, we can exist!” beneath the Antarctic Ice Shelf. This isolated water, between the seafloor and the glacier, isn’t exactly a subglacial lake, but this wasn’t someplace anyone expected to find life. 

IMAGE: “There’s all sorts of reasons they shouldn’t be there,” says British Antarctic Survey biologist Huw Griffiths. CREDIT: Dr Huw Griffiths/BAS

These critters were found living on a boulder 260 kilometers from the ice front while the researchers were digging boreholes for other geological and glaciological studies. This was a normally completely dark place, and the nearest sunlight was somewhere between 625 km and 1500 km away. Clearly, theorists need to dare to dream their lifeforms bigger, because life will find a way.

With so many missions going to Mars, the question on many minds has become “Can life find a way on Mars?” New experiments performed by NASA and the German Aerospace Center find that Earth life will unhappily survive, at least temporarily, in Martian conditions. Joint first author Marta Filipa Cortesão explains: We successfully tested a new way of exposing bacteria and fungi to Mars-like conditions by using a scientific balloon to fly our experimental equipment up to Earth’s stratosphere. Some microbes, in particular spores from the black mold fungus, were able to survive the trip, even when exposed to very high UV radiation. 

This is further evidence that black mold refuses to die, and this research gives us further reason to keep sterilizing all the spacecraft we send to Mars. If Mars has native microbes, we really don’t want to kill them with our microbes or accidentally generate a super microbe by letting things crossbreed. Mars does not need a black mold problem.

In parallel with that high altitude work, a team at the University of Vienna was looking at the chemistry of Mars to see if it could support life. Specifically, astrobiologist Tetyana Milojevic ground up a tiny piece of a Mars meteor and built a tiny Martian environment to see if a kind of microorganism that eats rocks — a chemolithotroph — would eat Mars rocks. The microbe, scientifically named Metallosphaera sedula, did indeed live. 

According to Milojevic: Grown on Martian crustal material, the microbe formed a robust mineral capsule comprised of complexed iron, manganese, and aluminum phosphates. Apart from the massive encrustation of the cell surface, we have observed intracellular formation of crystalline deposits of a very complex nature … which we did not observe previously when cultivating this microbe on terrestrial mineral sources.”

Yet again life found a way because it always does.

More Information

Black Hole Cygnus X-1 Farther, More Massive Than Thought

Scientists Claim High-Energy Neutrinos Born in Blazars

Neutrino Traced Back to Black Hole Tidal Eruption Event

Lakes Beneath Antarctic Ice Could Host Life

  • Imperial College London press release
  • “Dynamic flows create potentially habitable conditions in Antarctic subglacial lakes,” Louis-Alexandre Couston and Martin Siegert, 2021 February 17, Science Advances

Boulder Under Antarctic Ice Hosts Mysterious Sponges

Certain Microbes Could Survive Temporarily on Mars

Experiment Finds Life Can Survive on Martian Meteor Grains


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