Astronomers working with Fermi — a mission that is mapping the sky in gamma rays — have just released a new catalog of objects detected by the spacecraft. They’ve re-analyzed two years worth of data and have found nearly 2000 objects blasting out this super-high-energy form of light.

Here is the all-sky map they made from that data:

[Click to enhulkenate, and see a labeled version.]

The map is set up in galactic coordinates, so the Milky Way itself runs across the center. There are a lot of gamma-ray sources in our galaxy, most of which are bright simply because they’re close. Others are actually luminous sources like the Crab Nebula, various pulsars, and other violent objects. The map is very similar to one released by Fermi a while back, but this new one is more sensitive, and can see fainter objects.

About half the detected sources are active galaxies: distant galaxies with supermassive black holes at their hearts, actively gobbling down matter and spewing out vast amounts of energy in the process (black holes are sloppy eaters). The folks at Goddard Space Flight Center put out a nice, short video explaining this:

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Two stories just came out that I would love to spend time writing up in full, but I’m trying to get a million things done before I leave for Dragon*Con in the morning, so I’ll be brief:

1) Astronomers using the Chandra X-ray Observatory have discovered a binary black hole: two ginormous beasts orbiting each other about 500 light years apart in the center of the gorgeous spiral galaxy NGC 3393. Each has a mass of at least one million times that of the Sun. While binary black holes in the centers of galaxies have been spotted before, this is the closest one found: a "mere" 160 million light years away!

2) A newly-discovered planet (PDF) orbiting a star just 36 light years away appears to be at just the right distance to potentially have liquid water on its surface. The planet, HD85512b, orbits a star somewhat smaller and cooler than the Sun, but close enough to it that it actually gets more heat on average than Earth does. The planet is hefty, 3.6 times the mass of the Earth, but the size is not known (you get that from transit data, which we don’t have, and it would give us an idea of the surface gravity). So we don’t know anything about it, really, but if conditions are just so, it has the best potential we know yet for a planet with liquid water. Nat Geo has a great writeup of all this.

Now, if the Universe would kindly oblige not doing anything interesting for a few more hours, I can finish packing!

When it comes to black holes, there are some things we know a lot about them — in general. How they form, how they affect space around them, how they eat matter.

The details, though, are maddening. We know, for example, that black holes spin — as odd as that may sound — but how they get that spin and how spin changes over time is elusive knowledge.

A new study has given us an idea of that now, though. Here’s how this works: we see that as matter falls into them, some black holes generate twin beams, called jets, which shoot away from their poles. We see this from black holes that form when stars explode, and we see them in the supermassive black holes that inhabit the centers of all big galaxies, too. We know that various physical features of the jets are tied to the rate at which the black holes spin, and this new study makes this connection more clear. The astronomers used computer models to correlate spin to the jets, and observations appear to confirm these models.

Two very interesting results came out of the study. (more…)

A few years back I was working on creating educational products for the NASA orbiting observatories Fermi and Swift. These look at super-violent high-energy objects like exploding stars and black holes gobbling down matter. All big galaxies have supermassive black holes in their cores, and some are sloppy eaters, spewing out vast amounts of energy as the material makes The Final Plunge.

I remember finding images of one such galaxy, simply called the Circinus Galaxy, and being baffled as to why I had never heard of it or could find so little info on it. It’s only 14 million light years away, close for a galaxy! Turns out, it’s heavily obscured to visible light telescopes because it happens to lie in the plane of our own galaxy, and we have to look through lots of thick dust to see it. That dims the light a lot! But infrared light can pierce through that dust, making this an interesting object at wavelengths invisible to the human eye, colors that happen to be the specialty of NASA’s WISE spacecraft. So when astronomers took a look, well, behold!

What an awesome picture! [Click to blackholenate.]

There’s a lot to see here. (more…)

I have a morality tale to tell here, but first we have to do some science. The science is part of the moral, and it’s actually rather surprising and cool. And it was reading about the science that made me chuckle, because the moral to me — as a scientist myself — was pretty obvious, but I know to others it will be as opaque as black hole.

Speaking of which…

We know that at the heart of every big galaxy lies a supermassive black hole. There’s one at the center of our galaxy — tipping the cosmic scale at 4 million times the mass of the Sun! — and one in Andromeda. In fact, looking for these monsters^* was one of the key missions for building and launching the Hubble Space Telescope, a mission it had great success with.

There be monsters here. Click to supermassivate.

Why those black holes are there, and so huge, is a matter of some discussion. We’re pretty sure they formed at the same time as their host galaxies themselves, and in fact helped the galaxies grow at the same time the galaxies fed the black holes material. We also know that big galaxies like our Milky Way grew to their current enormous size by literally colliding with and eating other galaxies. This would inevitably lead to the doomed smaller galaxy’s black hole falling to the center of our galaxy, where the insatiable black hole already there would merge with it, growing bigger.

When this happens, so it’s thought, matter in the form of gas, dust, and stars would also fall into the center, feeding the black hole. The matter can pile up outside the hole and get incredibly hot — observations indicate it can reach many millions of degrees, blasting out light in the form of X-rays. Galaxies like these are called active, and we see them everywhere. And many of these active galaxies are weirdly shaped, distorted, indicating they may have recently undergone a big collision. Aha! That fits the idea that colliding galaxies feed black holes and make them active.

There have been so many observations of this that it has matured to become the standard assumption: most active galaxies have recently collided with another galaxy, dumping material into the core and triggering an outburst. I can’t tell you how many papers I’ve read about this, especially when I was working on the public outreach for the Fermi satellite, which was designed to look at active galaxies.

It’s a good story. The problem is, it looks like it’s wrong.

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Some 60 million light years from Earth is the monster galaxy M87. It’s a massive elliptical galaxy, one of the largest such in the nearby Universe… if you count 600 quintillion kilometers away as "nearby".

And when it comes to the Universe, I do.

It sits in the center of the Virgo cluster, a collection of roughly 1500 galaxies all bound to each other by gravity. At the heart of M87 is one of the biggest black holes ever seen: something like 6 billion times the mass of the Sun (the Milky Way has one as well, but it’s a paltry 4 million solar masses). It’s called a supermassive black hole, and it’s active. That means it’s a sloppy eater: as matter falls in to the hole, it piles up outside and forms a giant disk, which gets hot… millions of degrees hot. The tremendous heat and other titanic forces join up to blast away a huge amount of the otherwise incoming material. It’s not a nice, neat process, and when a black hole on that scale lets out a belch, it’s felt for hundreds of trillions of kilometers… as you can see in this image:

[Click to supermassivize.]

This is a composite of two images, one taken in radio wavelengths by the Very Large Array (in red) and the other in X-rays by the orbiting Chandra Observatory (in blue). The X-rays are being emitted by gas blasting away from the black hole, heated up by the disk and the magnetic fields affiliated with the hole itself. The radio waves are from gas that previously existed outside and farther away from the black hole, which is being slammed into, stirred up, and swept away by the outflowing gas.

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Leon Jenkins is the President of the LA chapter of the NAACP, the organization that advocates for equal rights for black people. The work they do is fine by me, and I support their efforts. But organizations are made up of individuals, and individuals can make mistakes.

This is really one of those times. Here’s the story: Hallmark came out with a card for recent graduates, and it’s one of those deals that has a speaker in it that activates when you open it. Like all such cards it’s twee and sugary and over the top. It involves two cartoon characters with squeaky and high-pitched voices talking about how the graduate can now take over the world. It has an outer space theme to it, and what they say, well… watch/listen for yourself:

Um, yeah. It’s pretty clear to just about anyone who hears it — and doesn’t have any particular stake in the claim — that the card is saying “black holes”. The space theme is obvious enough, and black holes are a common topic. So why on Earth would someone think the card is saying “black whores”, as Mr. Jenkins and other LA NAACP members do?

In fact, there’s a good reason. What we have here is a very well-understood topic to skeptics: audio pareidolia. (more…)