Astronomy.com blog : black holes

Send us your astronomy questions

Liz Kruesi — Wed, 15 Jul 2009 21:05:00 GMT

Perplexed by planets? Confused by cosmology? Baffled by black holes? Then send in your questions to Astronomy magazine at askastro@astronomy.com.

If you have an astronomy question about observing, the planets, stars, cosmology, or astronomy history, send it in! Five are selected each month for publication in the Ask Astro section of Astronomy magazine. If your question is selected, we will forward it to an expert for his or her response. Then, the question and answer will appear together in a future issue. We may edit or revise your question for clarity.

We aren’t always able to respond to questions individually. But please keep the questions coming — they help us to learn what our readers are interested in, and what topics we should consider for future coverage in the magazine.

Join the pulsar hunters and work from home

Daniel Pendick — Thu, 26 Mar 2009 19:13:00 GMT

“Wanted: a few hundred thousand computers with a little spare time on their hands.”

That’s the basic job qualification if you (and your personal computer) want to join Einstein@Home, a massive international project that uses donated personal computer time to crunch data for real scientists. The project has been going on for several years. This week, Einstein@Home announced it will begin to analyze data from a new source: the giant radio telescope at Arecibo Observatory in Puerto Rico. It’s not too late to get into the action.

Einstein@Home, based at the University of Wisconsin-Milwaukee (UWM) — a short drive down I-94 from Astronomy headquarters — and the Albert Einstein Institute (AEI) in Germany, is one of the world’s largest public volunteer distributed computing projects. Some 220,000 people in 209 countries have signed up for the project and donated time on their computers to analyzing data collected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and GEO 600 (in Sarstedt, Germany) for gravitational waves.

Powerful astro-events, like black-hole mergers, should generate ripples in the very fabric of space-time (gravitational waves). Einstein@Home uses the collective number-crunching power of thousands of computers to look for patterns of gravitational waves hiding in data captured by LIGO and GEO 600.

The researchers with Einstein@Home will be searching the Arecibo data for a special type of astronomical odd couple that generates gravitational waves: a spinning neutron star, or pulsar, orbiting a black hole. Both objects spring from the collapse of massive stars.

Previous methods could find such binaries in radio data if they orbited each other every 50 minutes or longer. Using the collective computing power of its volunteers, Einstein@Home will be able to find pairs with orbits as short as 11 minutes.

Many dedicated amateur astronomers contribute to various kinds of research, like the study of variable stars and discovering and tracking asteroids and supernovae. But if stargazing isn’t your thing, here’s a way to do some astronomy by essentially doing nothing.

Well, not exactly. You do have to sign up for Einstein@Home and install some software. The project team expects to spot at least a few new pulsars per year.

To find out how to participate, go to einstein.phys.uwm.edu.

AAS meeting, Wednesday recap

Liz Kruesi — Thu, 08 Jan 2009 23:01:00 GMT

Well, Wednesday was my shortened day. I was at the meeting for only the morning. In that time I went to three press conferences and wandered around some of the posters … all before 1:15 p.m. Then I had to bug off to grab my shuttle to the airport. Today was a lot of high-energy and cosmology — the really cool stuff, in my opinion.

The first press conference covered an interesting black-hole observation. For years astronomers have had their own “chicken-and-egg” problem: What came first, supermassive black holes or their host galaxies? Research by an international collaboration, led by Chris Carilli of the National Radio Astronomy Observatory (NRAO), has found evidence that suggests black holes may have come first.

Earlier studies of supermassive black holes and their galaxies’ central bulges have shown a linear relationship between their masses. This relationship is valid across a wide range of masses and galaxy ages. The black hole’s mass is roughly a thousandth the size of the galactic bulge. This is all well and good, but astronomers really aren’t sure why this relationship exists or when in the lifetime of the galaxy (and black hole) this relationship kicks in.

One way to test this relationship is to look at galaxies from early in the universe’s history. Carilli and colleagues did just that. They observed the emission lines of four galaxies roughly 1 billion years after the Big Bang. The width of these spectral lines corresponds to the gravitational field of the supermassive black hole at each galaxy’s center. Therefore they obtained both the black hole’s mass and the bulge mass of these galaxies. What they found is the linear correlation between the two does not hold in the early universe.

“The black holes in these young galaxies are much more massive compared to the bulges seen in the nearby universe,” said Fabian Walter, another team member, of the Max-Planck-Institute for Radioastronomy in Germany. This implies that the black holes started accumulating mass first.

The researchers do acknowledge, however, that this observation is based on just four galaxies — and four massive galaxies. Each galaxy took about 100 hours to observe, which is why they have so few data points. In the future they plan on extending the search to slightly nearer galaxies, and more “normal” galaxies, compared to the extremely massive and luminous four they studied. Telescopes now under construction — such as the Expanded Very Large Array, the Atacama Large Millimeter/submillimeter Array, and also the James Webb Space Telescope — should help fill in additional data.

Another neat press conference from today concerned a weird, and completely unexpected, extragalactic radio signal. Researchers using NASA’s ARCADE balloon (Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission) observed radio emission some six times brighter than the combined radio emission of all the galaxies in the universe. And they weren’t looking for it.

ARCADE’s initial science goal was to measure the heat signature of the first stars to form after the Big Bang. While the first stars themselves can’t be observed, they would heat up the surrounding gas. The gas then emits radiation in the infrared. This infrared signature is what ARCADE was looking for.

ARCADE uses seven radio receivers immersed in 500 gallons of liquid helium to cool the detectors to 2.7 degrees above absolute zero. From 120,000 feet above eastern Texas, ARCADE observed about 7 to 8 percent of the sky. The researchers, led by Alan Kogut of NASA’s Goddard Space Flight Center, analyzed the signal and removed the foreground galactic signal. What they got was a far-too-bright radio signal. They determined it can’t be a result of the first stars — it’s just too bright. Their analysis also ruled out all known radio sources, and they’re quite sure the signal is coming from outside the galaxy. This wasn’t the first time the signal was observed, but it was the first time it was analyzed in detail. A few previous research groups had detected this signal, but never followed up or seemed to question it.

The ARCADE team was quite surprised to find this signal, to say the least. They also said the signal is likely not associated with the cosmic microwave background, but is likely connected with infrared. Future experiments with finer resolution are needed to further analyze this signal.

AAS meeting, Tuesday

AAS meeting, Monday

The Milky Way’s center of attention

Daniel Pendick — Wed, 10 Dec 2008 17:29:00 GMT

Did a parent, boyfriend/girlfriend, spouse, supervisor, etc., ever say to you in an argument, “You’re not the center of the universe, you know!”

Well, sorry to disappoint, but you’re not the center of the galaxy either.

That honor belongs to a black hole that weighs between 4,250,000 and 4,370,000 times the Sun’s mass and lies somewhere between 26,028 and 27,169 light-years from Earth.

How do I know? Because German astrophysicist Reinhard Genzel and his team at the Max-Planck-Institute for Extraterrestrial Physics in Garching near Munich recently reported the results of a 16-year study tracking the orbits of 28 speedy stars as they zip around the galactic center. The only object with enough mass to account for the stars’ orbits is a black hole.

We knew that black hole was there, but estimates of its mass and distance varied. In an article I edited last year, I said “3 to 4 million solar masses.” Now we have a nice, solid number for each. Genzel won the prestigious Shaw Prize in Astronomy for 2008 for this research.

Nice, solid numbers make science editors sooooo happy. No longer will awkward phrases like “according to scientists’ best estimate yada yada yada” appear in my work. I can just say “about 27,000 light-years” and “about 4 million solar masses.” In fact, I just did — this morning, as I was putting the final touches on a story mentioning the Spitzer Space Telescope’s discoveries about the Milky Way.

This study appears in the December 20 issue of The Astrophysical Journal.

Astronomy previews the Large Hadron Collider's big day

Matt Quandt — Tue, 09 Sep 2008 19:47:00 GMT

I sat down with Astronomy magazine Senior Editor Rich Talcott to learn more about the Large Hadron Collider (LHC) and its September 10 test.

For additional background information on the LHC, visit Astronomy.com.

UPDATE: LHC successfully passed its September 10 test.

Here is the transcript of my conversation with Rich:

What is the Large Hadron Collider?

Well the LHC, as the name implies, is something that’s big, that’s going to collide elementary particles called hadrons. And basically what these guys are are subatomic particles that consist of quarks and are held together by the strong nuclear force. The LHC is going to collide hadrons at tremendous energies.

The most well known hadrons are neutrons and protons. And what the LHC is going to do mainly is collide protons together at stupendous speeds.

The particles are going to be traveling around the 17-mile [16.57 miles] circumference at within one millionth of one percent of the speed of light. We’re talking 99.999999 percent the speed of light.

At those speeds, there’s going to be a tremendous amount of energy released whenever the protons collide. The ring actually has six different experiments that are going to be looking for different results when these particles collide.

The protons make 11,000 trips around the 17-mile loop every second. So it’s 11,000 revolutions per second.

And when it’s fully functioning, they’ll be colliding 600,000,000 protons together at a time. So we’re talking a large number of high-speed protons coming together.

To make this device work, it needs to be cooled to a very low temperature. So it’s 1.9 Kelvin above absolute zero, which means 1.9 degrees Celsius above absolute zero. So it’s extremely cold magnets that are going to keep the particles moving around the circle so that they can be collided together.

Also as you might expect the particles moving around inside this thing would naturally run into air molecules and create collisions as well. So one of the things that they’re going to do is create a vacuum that’s equal to interplanetary space, or actually about 10 percent the density of the Moon’s atmosphere. It’s going to be an extremely good vacuum inside here so that the protons don’t interact with all sorts of other things before they run into each other heading in opposite directions.

What do scientists hope to learn from the LHC experiments?

There are two different ways that scientists are looking at the LHC and what it can do for them. Both physicists and cosmologists are really interested in what’s going on here. And it’s high-energy physicists that get the big play here. One of the particles that scientists believe exists, but has never been detected before, is called the Higgs boson, and it’s also been called the “God particle” because it has such special properties.

Among them being the fact that a lot of scientists think this is the particle that confers mass on every other particle in the universe. So scientists are deeply concerned about finding this particle to learn its properties to see if there may be different versions of this particle out there. We haven’t had an experiment yet that’s been able to reach the energies necessary to create these particles, and so that’s one of the hopes here.

Some people may wonder how colliding particles like protons together actually could create anything because most of the time collisions tend to destroy. But if you remember back to Einstein’s famous equation, E=mc^2, matter and energy are just two different versions of the same property essentially. And so when you’re colliding these particles together the tremendous energy can create matter, and that’s what the scientists are hoping for.

So LHC could reveal God? [laughter]

Well, one of his particles anyway.

The other reason that the Higgs boson is so important to physicists trying to study how the universe is put together is that it’s an essential ingredient in the standard model that physicists have developed to describe how matter works.

These kind of go together into what are often called the grand unified theories that combine the electromagnetic force along with both the strong and weak nuclear forces. And these three of the four forces in the universe are combined in the standard model, and the Higgs boson is essential to making that standard model work.

If the LHC does not turn up the Higgs boson, then that means physicists have to go back to, if not to square one, at least to a low number square in order to be able to figure out how the universe works.

The other aspect that the LHC is going to look at, or what makes cosmologists perhaps most interested is that the conditions that are going to be created within the LHC are the same conditions that existed very early in the universe back when it was less than a second or so old.

And this is going to be the first controlled experiment that we’ve ever had that is going to be able to look back and see what conditions in the early universe are like. So among the things cosmologists are interested in learning is how come there’s a lot more matter than antimatter in the universe. Theory says there should be equal amounts of both. But because whenever matter interacts with antimatter it turns into energy, there shouldn’t be any matter here in the universe; it should’ve all been exploded into energy. Obviously we do have a lot more matter than antimatter, and so there’s some fundamental difference between matter and antimatter, and one of the things that the LHC may be able to get at is what that difference is.

Another thing that they’re going to be looking for is information about dark matter and dark energy, which together make up about 96 percent or so of the mass and energy in the universe. The LHC is going to be looking for something called supersymmetric particles, which may well have a role to play in dark matter and what that is, and so this is going to try to give astronomers and cosmologists an idea of what a good fraction of the universe is made out of.

One other thing that may help cosmologists out is that some of the particles and conditions created may be enough to see whether space has more than the three dimensions that we’re familiar with.

This is one of the things that string theory, a favorite of science-fiction writers and scientists who like to really think out there. String theory may be a way of combining gravity with the three forces that the grand unified theories attempt to unite. One of the predictions of string theory is that there should be many more dimensions than just the three or four of space-time that we tend to think of here in our universe. If it can get at looking at some of these potential extra dimensions, that may give the first experimental evidence of string theory.

What’s happening September 10?

The next big step in the commissioning of the LHC comes on September 10. They’re going to circulate a beam throughout the 17-mile-long tunnel.

The actual first high-energy collisions aren’t going to happen until it’s officially commissioned, and that’s on October 21. Or at least, that’s the current date. So we still have more than a month left before they start colliding these protons at super-high energies to see what comes out.

So September 10 is a test of their being able to circulate the beams and getting them up to the speeds that they want to.

Which is probably, just throwing out a number, 9/10 of what they want to do to make sure everything’s working. If they can circulate a beam, they can presumably circulate them in both directions and collide them. So it’s kind of a minor step beyond being able to circulate the beam at high speeds.

How do they produce the particles?

There’s a linear accelerator that injects the particles into the circular ring, and so it starts the particles at very high energies. The magnets then speed up the protons and keep them moving around the circular path.

They start with high-speed protons that get sped up inside the ring.

Have these experiments ever been done before?

This is easily the highest energy experiment that’s been done, and there have been other experiments that have gone on that have reached lower energies and that have found out much of what’s going on in the universe. So we have a lot of good evidence that the standard model is true based on what earlier experiments have shown. But we haven’t been able to get to the energies needed to see the Higgs boson and to see some of these other effects, so we’re trying to get up to the energy needed to be able to see the next stage of the evolution of the models and the experiments.

So it could confirm what we’ve learned, or it could provide evidence that forces physicists to go back to square one?

It’s always interesting. If scientists knew what an experiment would show, there wouldn’t be any need to run the experiment. This experiment is like all others — basically, we don’t know for sure what it’s going to show, so one of the things is if it finds the Higgs boson and it has the properties physicists expect, then that goes a long ways toward confirming the standard model of particles.

But if the Higgs boson doesn’t exist at what scientists expect, then they’re going to have to go back and try to figure out where the Higgs boson may fit in, if it has different properties, or if they don’t find the Higgs boson, how matter is actually put together and what causes mass in the universe because that’s what the Higgs boson is supposed to be able to do.

Where did the funding come for LHC?

There are actually more than 8,000 scientists and more than 80 countries involved in the LHC and something like 400 universities, so the money came from all of these participants in the project.

Is it the largest collaborative science experiment in the history of science?

Yeah, I think that would be fair to say.

Along the outside of the ring, there are six different experiments set up so it’s not a single experiment; there are going to be six different experiments looking for different things from the proton collisions. And so, you wouldn’t say all 8,000 people are working on the entire thing. There are lots of sub-disciplines that people are working on or experiments that may not have anything to do with the other experiments.

One of the fun things is looking at the author lists on high-energy particle physics papers and these are going to be ... there have been some high-energy particle physics papers that have more than 100 authors on them, and these won’t be any smaller.

Where does LHC rank in terms of scientific instruments throughout history? Bigger than Hubble?

The amount of data that we’re going to get from the LHC, to put it in perspective, it’s enough that if you put it all on CDs, every year there will be enough CDs to go to the Moon and back twice.

So there’s a huge amount of data that is going to come out of this, and it’s teasing out the small effects from that data that’s going to give us all the knowledge that we hope. It’s fair to say that in terms of the basic scientific knowledge that we can and should get out of the LHC, it’s going to be certainly at least as much as Hubble does, but it’s not going to be in the same sense of pretty pictures of what the universe looks like. The universe of the very small is far different from the universe of the very large, and you may have to be a scientist to appreciate the beauty of the very small.

It’s the first controlled experiment that’s going to be able to look back at what conditions were like very shortly after the Big Bang. So we are going to get a look at the universe’s origins in a way that we haven’t had the chance to do before.

What are the potential dangers of flipping the switch September 10?

You may still run across on the Internet examples of people talking about how Mars at this opposition is going to look as big as the Full Moon. Most of the purported problems that are associated with the LHC kind of fall into that same realm of people taking a little bit of knowledge and using it to advance far beyond what might possibly happen.

One of the things that people have talked about is the production of the mini black holes by the particle collisions, and that’s not totally out of the realm of possibility. The thing about black holes it that they tend to evaporate over time, and the smallest black holes evaporate the most quickly. Any black hole created by these particle interactions would disappear within a small fraction of a second, something along the order of a billionth of a billionth of a billionth of a second. So any of these black holes would evaporate before they would have a chance to start devouring anything around them.

People have talked about [LHC creating] conditions that have never been created before in the universe, or not since the Big Bang, which is not necessarily true. We have things called ultra high-energy cosmic rays that rain down on Earth’s atmosphere and these things, believe it or not, have energies far greater than the energies that we’re going to have in these collisions.

Something on the order of a million times stronger; we’ve seen cosmic rays with those energies. Those cosmic rays run into molecules in Earth’s atmosphere and so far haven’t created any black holes that have swallowed Earth or created any strange particles that have developed into anything that could threaten Earth. The fact that the universe is creating experiments similar to what the LHC is going to do, just not in a controlled way, is the best proof that we don’t have anything to worry about here.

Back when they exploded the first atomic bombs in the 1940s, there were a few scientists that predicted that it could launch a chain reaction that would essentially ignite the atmosphere of Earth and burn out all the oxygen in Earth’s atmosphere. That probably had a bigger chance of coming true than this does.

Michio Kaku, a theoretical physicist and someone who has written for Astronomy before, said “These things may be possible, but, technically, so is the fact that the LHC could create a fire-breathing dragon, and they’re about equally probable.”

NASA creates an astro-buzz

Daniel Pendick — Fri, 09 May 2008 16:50:00 GMT

Have NASA astronomers discovered the black hole in the Milky Way’s center where lost socks turn into X rays? Tune in next week to find out. Ute Kraus (Max-Planck-Institut für Gravitationsphysik)

NASA has found something amazing in our galaxy. Unfortunately, it’s not saying just what it has found — until next week, when it collects enough reporters for a press conference.

Or, if you want it from the horse’s mouth, here is the exciting, taunting first paragraph of a pithy press release from our friends in the national space business:

WASHINGTON — NASA has scheduled a media teleconference Wednesday, May 14, at 1 P.M. EDT, to announce the discovery of an object in our galaxy astronomers have been hunting for more than 50 years. This finding was made by combining data from NASA's Chandra X-ray Observatory with ground-based observations.”

That means I have to wait 5 days before NASA reveals yet another Secret of the Universe. And it better be good. It better be the astronomical equivalent of an X-Box release or a taped conversation between a ranking U.S. Senator and his mistress.

What, oh what, could it be?

My first thought was, “They finally took a picture of the supermassive black hole at the center of the galaxy.” That made sense, especially since Chandra is involved. We commonly see lots of X rays beaming from black holes as gas and other junk spirals in and approaches the speed of light.

But how to know for sure? I did what any professional busy-body in the media would do: I e-mailed unnamed, shadowy sources in the astronomical community to see if they knew what NASA is up to and — more important — if they would be willing to rat out NASA (off the record, of course). I received this response:

Chandra does suggest something energetic, but we already know there is a supermassive black hole at the Galactic Center. I just polled a couple of my X-ray colleagues about what it could be given the clues at hand, but no one had any great idea about what we might have been searching for over the last 50 years. Hard to disentangle the usual press-release hype.

Well, no easy answers, it seems. All I can do is use my imagination. If NASA were to find something hidden somewhere in the galaxy, what would it have to be to justify a week of media build-up hype?

The exoplanet where all of my lost socks go? Perhaps there is a wormhole connecting the lint trap in my dryer to the planet. That would be pretty cool.

Or maybe Jimmy Hoffa? Oh, in case you were born in the 1970s or later, and have no idea what I’m talking about, click THIS LINK.

Oh, I know: They found the black hole that the Mafia threw Jimmy Hoffa into.

All I can say, NASA, is this better be good.

John Archibald Wheeler (1911–2008)

Francis Reddy — Mon, 14 Apr 2008 21:27:00 GMT

Best known to astronomical trivia buffs as the man who coined the term “black hole,” University of Texas physicist John A. Wheeler died this morning at the age of 96.

Wheeler “was legendary for his way with words, coining such terms as wormholes, quantum foam, black holes, and the wave function of the universe,” writes Wheeler’s former student and current University of Chicago physicist Daniel Holz over at Cosmic Variance. Wheeler’s scientific resume extended from quantum mechanics — he collaborated with Niels Bohr on early nuclear fission research — to cosmology, but he’s best known for his contributions to general relativity.

“For the first half-century of its life, general relativity was a theorist’s paradise, but an experimentalist’s hell. No theory was thought more beautiful, and none was more difficult to test.” That summary comes from the 1973 edition of Gravitation, the bible of relativity, written by Charles W. Misner and Kip S. Thorne — two former students of Wheeler’s — and, of course, the man himself.

The chapter concludes that relativity “has emerged from each of its tests unscathed — a remarkable 1973 tribute to the 1915 genius of Albert Einstein.” It’s a remarkable 2008 tribute as well, for relativity still reigns supreme.

Following the implications of relativity’s equations led physicists to ponder black holes. In 1939, J. Robert Oppenheimer and Hartland Snyder at the University of California, Berkeley, used them to show that when a big enough star runs out of fuel, it must collapse to densities so great even light cannot escape it. Moreover, the collapse continues forever.

At first, Wheeler fought the notion that a collapsing mass could cut itself off from communication with the rest of the universe. But, by the mid-1960s, intense theoretical work showed there was no way of avoiding these so-called “frozen stars.” In 1967, Wheeler hit on a more dramatic — yet scientifically justified — term: black hole.

By then, astronomers had already identified a candidate — now considered a confirmed — black hole. The object, named Cygnus X-1, is one of the brightest X-ray sources in the sky. The radiation arises as gas stolen from a blue supergiant streams onto a disk of matter gathered around a stellar-mass black hole. A few dozen such systems are known.

These are small-fry compared to their supermassive brethren at the cores of galaxies. The black hole at the Milky Way’s center weighs in at 3 to 4 million Suns.

But back to Wheeler. Those interested in hearing these developments in the physicist's own voice should consult his science autobigraphy, Geons, Black Holes, and Quantum Foam: A Life in Physics, written with Kenneth W. Ford (W. W. Norton & Co., 2000).

Light, mirrors, gravity!

Francis Reddy — Mon, 10 Mar 2008 21:40:00 GMT

Yesterday’s Milwaukee Journal Sentinel ran a nice summary of efforts by the University of Wisconsin - Milwaukee to detect gravitational waves. The article focuses on NEMO, the $1.8 million, 1,560 CPU, Beowulf-class computing cluster built and operated by the school’s gravitational-wave group. (Ah, I love that kind of talk.)

NEMO was commissioned in 2006. Since then, it’s been chugging through data produced by the Laser Interferometer Gravitational Wave Observatories (LIGO) in Hanford, Washington, and Livingston, Louisiana. Here’s an informative cartoon of the setup.

These facilities bounce lasers back and forth to track length changes smaller than the diameter of a hydrogen atom. Such changes would occur when gravitational waves pass by and ripple through our local space-time. Relativity predicts such things, but so far, no one has detected them.

Scientists continually are improving the reach and sensitivity of these observatories. Sooner or later, they’ll detect signals from things like inspiraling pairs of neutron stars or black holes, core-collapse supernovae, and possibly even gravitational waves from the Big Bang.

You can participate, too. Since early 2005, LIGO data has been distributed to personal computers and processed using the Einstein@Home project’s nifty screensaver. This gives users eye candy in return for background use of their computers (more about it here).

Einstein@Home lets users “compete” as teams. I formed Team Astronomy as soon as the project went public. We now boast 69 members with computing credits, which are points awarded based on the amount and speed of data processing by each computer.

Team Astronomy now ranks in the top 45 in terms of recent average credits, but I think we can do better. Feel free to join us in search of gravitational waves. It may be the closest you’ll get to a Nobel prize.

A black hole named Edd

Francis Reddy — Fri, 11 Jan 2008 14:52:00 GMT

One of the pleasures of attending American Astronomical Society meetings is strolling through a sea of poster papers. A poster paper is exactly what it sounds like — it’s an oversized page that summarizes the results of a single study.

Now and then, you spot displays where the science comes mixed with whimsy. Such is the case with “Discovery and Interpretation of an X-ray Period in the Galactic Center Source CXOGC J174536–2856,” a study led by Valerie Mikles at the University of Florida. The poster features art of a massive star blowing a dense stellar wind toward a putative black hole represented by … Godzilla. (PDF here; be warned, it’s large.)

Mikles and her colleagues nicknamed the object Edd-1, which is hardly your typical astronomical moniker. “It actually has no scientific significance whatsoever,” she says.

The story: She first presented this source in an earlier poster that included a picture of Edvard Munch's "The Scream." “I used ‘The Scream’ because the iron line and the hydrogen lines are screamingly bright — the iron line is one of the largest ever seen,” Mikles explains. The line comes from iron atoms that have lost 24 electrons (FeXXV). “It’s stripped pretty bare,” she says.

So, the “Ed” in Edd-1 comes from Edvard. The second “d” is a pop-culture reference to “Ed, Edd n Eddy” on Cartoon Network. “That's why Edd-1 is a nickname and not an alternative name, like Cyg X-1,” Mikles notes.

It’s also lots easier to type than CXOGC J174536–2856.

After dealing with the nickname, the science is pretty straightforward. Observations using NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton reveal that Edd-1’s X-ray flux waxes and wanes over 189 days. That’s possibly an orbital period, and, if it is, the changes in brightness could occur because the X-ray source regularly becomes eclipsed. Alternatively, the changes might be due to variations in the fuel supply fed to an accreting object, like a neutron star or a black hole.

Combined with infrared observations taken with NASA’s Infrared Telescope in Hawaii, the emerging picture of Edd-1 is consistent with a binary where at least one object is a massive star throwing off a thick stellar wind. If the other object is also a massive star, the X rays could arise where these winds collide.

But Edd-1’s infrared spectra don’t seem very similar to those of known massive-star binaries, with O-type or Wolf-Rayet stars. So, Mikles thinks the companion is a neutron star or a black hole. It’s difficult to distinguish between them, she explains, but, if she were betting on it: “I’d say it’s a black hole.”