Scientists Find a Black Hole the Size of 21 Billion Suns

Scientists Find a Black Hole the Size of 21 Billion Suns

"They're huge. They're voracious. They're blacker than a panther on a moonless night. They're black holes, the mind-bending, space-warping cosmic objects with gravity so insanely powerful that even a beam of light that wanders too close will be sucked in, never to emerge. Einstein's theory of general relativity predicted they might exist, but the great physicist himself doubted it would really happen.

Einstein was wrong. Over the past decade or two, black holes have been discovered all over the place — small ones peppered around the Milky Way and huge ones, impressively called "supermassive" black holes, lurking the centers of galaxies. The one at the core of Milky Way weighs as much as a couple of million stars, and it could swallow the sun without even noticing, the way you'd swallow a pistachio.

But that's positively puny compared with the two new black holes, each about 330 million light-years away or so, just announced in the journal Nature. The smaller one, located inside a galaxy known as NGC 3842, is as massive as 9.7 billion suns, and the other, in a galaxy called NGC 4889, is more than twice as large: if you put it on a very large balance, it would take at least 21 billion stars to even things out. Another way to think about things: even the smaller of the two is nearly 30% bigger than the previous record holder, announced last winter, and it would make for a great storyline if astronomers were surprised, amazed, flabbergasted, blown away by the awesome giganticness of these monsters. Truthfully, though, they kind of expected it. "If we infer the existence of quasar black holes of ten billion solar masses at early cosmic times," Harvard theorist Avi Loeb told Nature's Ron Cowen for the journal's online news blog, "we'd better find their counterparts in the present-day Universe."

Loeb is referring to quasars — beacons of light so intensely bright they can be seen halfway across the universe. When astronomers first spotted them in the late 1950s, nobody knew what they were. Nowadays, everyone pretty much agrees that quasars are supermassive black holes at the cores of young galaxies. The holes themselves aren't visible, of course, but when they suck in surrounding matter, the stuff heats up to millions of degrees, sending bursts of energy shooting across the cosmos.

Back when the universe was young, there was plenty of gas floating around to feed these monsters. Nowadays, much of it the gas is gone, and so are the quasars — but the black holes that powered them should, as Loeb says, still be around (where would they go, after all?). Now, thanks to some of the world's most powerful telescopes, astronomers know that indeed they are. While scientists can't see the black holes directly, they can see stars whipping around at high speeds in the two galaxies' cores — and by clocking those speeds carefully, the astronomers can calculate how big and how dense the object they're orbiting must be. In each of these cases, nothing but a supermassive black hole fits the bill.

Such observations are technically difficult, so in one sense the latest black-hole discoveries are extraordinary. Still, astronomers expected to find such things all along, so it might not seem like such a big deal to space experts. Indeed, Martin Rees, the British astronomer royal, dubbed the new results "an incremental step" in the New York Times, with nary a word about shock or awe. If you've got a professional interest in how black holes were born and how they evolved, this is more grist for the mill.

For the rest of us — well, they're just kind of awesome."

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How Much for a Room at Earth's First Space Hotel?

How Much for a Room at Earth's First Space Hotel?

"Imagine waking up as your alarm's going off, reaching over and opening a window...and gazing out at terra firma in repose. No, not a poster of planet earth affixed to your window, but the real deal, viewed from your very own hotel suite, hundreds of miles above the planet's surface.

If a bunch of Russian engineers and Russia-based company Orbital Technologies have their druthers, it could happen to you (granted a very wealthy you). It'll be called the Hotel in the Heavens, according to The Guardian, a four-room zero-gravity orbital inn located at the crossroads of Yes and No Joke.

"The hotel will be aimed at wealthy individuals and people working for private companies who want to do research in space," says Orbital Technologies' CEO Sergei Kostenko. "A hotel should be comfortable, and this one will be." Comfortable enough for space, anyway—those four rooms will accommodate up to seven people.

What'll it cost? About $984,000, or nearly a million bucks per visitor for five days aboard—that's $164,000 for the ride to and from, and $820,000 for lodging. If you're sitting on that kind of spare coin, don't look for this celestial abode to grace a travel-booking website anytime soon, because it sounds like we're in for a five year wait before the space dock's doors open.

The hotel itself will cost $60 million, serve as a kind of fallback spot for the International Space Station should things ever go awry there, and it'll take two days to get to, courtesy one of Russia's not-so-posh Soyuz spacecraft. Guests will have access to showers and air-flush toilets, sleep in bags attached to walls (you pick your orientation) and enjoy some of the best food this side of, well, whichever side you're facing as you whip around the planet once every 90 minutes, enjoying 16 sunsets and sunrises daily."

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Hot Jupiter

Hot Jupiter

 

“The Blackest Planet in the Universe: How Astronomers Discovered a Dark, Glowing 'Hot Jupiter'" ”

“From the moment astronomers first began finding planets around other stars in the mid-1990's, they realized that their scientific imaginations had been far too tame. Everyone assumed that alien solar systems would resemble ours, with small, rocky planets like Mars and Earth closer to the center and big, gaseous blobs like Jupiter and Saturn further out. But with the discovery of new exoplanets, as they're now known, astronomers began to toss their assumptions out the window: Everywhere they looked, they saw big and gaseous planets, like Jupiter, that orbited closer to their stars than anyone had thought possible —closer even than our own scorched Mercury.

By now, the existence of these so-called "hot Jupiters" is no longer big news. Instead, it's the color of one new discovery that has startled scientists. If you imagine the blackest thing you've ever heard of — a lump of coal, say — and then try to imagine something a whole lot blacker, you're beginning to get a sense of the planet known by the strange name of TrES-2b. Where the original Jupiter reflects about 50% of the sunlight that hits it, TrES-2b reflects an infinitesimal 1%. "Actually," says David Spiegel, a Princeton astronomer who co-authored the new study on TrES-2b's remarkable blackness that appears in Monthly Notices of the Royal Astronomical Society, "our best models suggests it's more like a tenth of a percent."(See photos of Hubble's greatest hits.)

Still, the craziest thing about this discovery is that it may not be all that crazy. Astronomers have long suspected that hot Jupiters should be relatively dark. The real Jupiter has an atmosphere made mostly of hydrogen gas, with light-reflecting clouds of frozen ammonia and various other substances. TrES-2b is mostly hydrogen as well, but since it's only 3 million miles from it's star — more than 160 times closer than Jupiter is to the Sun — TrES-2b simmers at a toasty 1,800 degrees. At those temperatures, things like sodium and potassium, which would otherwise be solid, evaporate to form gases — gases that are then spread very thin. For every molecule of potassium or sodium, the atmosphere has a million atoms of hydrogen. But these molecules are so efficient at absorbing light that even under the intense glare of the nearby star, the planet reflects much less light than you'd expect.

It does, however, glow, which is how the astronomers made their new discovery in the first place. From the vantage point of Earth, TrES-2b's orbit takes it right in front of its star, then behind, then in front again, over and over. When the planet is about to duck behind the star, its day side faces us, so whatever light we're seeing is a combination of planetary light and starlight. When it's about to pass in front, we're seeing the planet's night side, so all we're seeing is the star. By comparing the two, Spiegel and his co-author, Harvard astronomer David Kipping, could determine how much light the planet alone was contributing (it was six one-millionths of the overall light, if you're keeping count). And virtually all of that light could be accounted for by the 1,800-degree atmosphere, glowing like a hot coal.

The greatest mystery of TrES-2b is that, given what astronomers think they understand about hot Jupiters, there shouldn't be enough potassium or sodium to make this particular planet as black as it appears to be. "There could be an overabundance of them," says Spiegel, "or there could be some other molecules involved, such as titanium oxide, but it would be hard to get that into the upper atmosphere. It really is a mystery."

Solving that broader mystery will have to wait for a more detailed study of TrES-2b's glow — and that, says Kipping, will probably require the James Webb Space Telescope, the Hubble's successor, which is now under construction. Unfortunately, it's way over budget and behind schedule, and just last month a Congressional subcommittee threatened to kill the project altogether.

If that threat holds up, the blackest thing this side of a black hole may go unexplained for a very long time. “

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