Space is typically thought of as a very quiet place. But one team of astronomers has found a strange cosmic noise that booms six times louder than expected.
The roar is from the distant cosmos. Nobody knows what causes it.
Of course, sound waves can't travel in a vacuum (which is what most of space is), or at least they can't very efficiently. But radio waves can.
Radio waves are not sound waves, but they are still electromagnetic waves, situated on the low-frequency end of the light spectrum.
Many objects in the universe, including stars and quasars, emit radio waves. Even our home galaxy, the Milky Way, emits a static hiss (first detected in 1931 by physicist Karl Jansky). Other galaxies also send out a background radio hiss.
But the newly detected signal, described here today at the 213th meeting of the American Astronomical Society, is far louder than astronomers expected.
There is "something new and interesting going on in the universe," said Alan Kogut of NASA's Goddard Space Flight Center in Greenbelt, Md.
A team led by Kogut detected the signal with a balloon-borne instrument named ARCADE (Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission).
In July 2006, the instrument was launched from NASA's Columbia Scientific Balloon Facility in Palestine, Texas, and reached an altitude of about 120,000 feet (36,500 meters), where the atmosphere thins into the vacuum of space.
ARCADE's mission was to search the sky for faint signs of heat from the first generation of stars, but instead they heard a roar from the distant reaches of the universe.
"The universe really threw us a curve," Kogut said. "Instead of the faint signal we hoped to find, here was this booming noise six times louder than anyone had predicted."
Detailed analysis of the signal ruled out primordial stars or any known radio sources, including gas in the outermost halo of our own galaxy.
Other radio galaxies also can't account for the noise – there just aren't enough of them.
"You'd have to pack them into the universe like sardines," said study team member Dale Fixsen of the University of Maryland. "There wouldn't be any space left between one galaxy and the next."
The signal is measured to be six times brighter than the combined emission of all known radio sources in the universe.
For now, the origin of the signal remains a mystery.
"We really don't know what it is,"said team member Michael Seiffert of NASA's Jet Propulsion Laboratory in Pasadena, Calif.
And not only has it presented astronomers with a new puzzle, it is obscuring the sought-for signal from the earliest stars. But the cosmic static may itself provide important clues to the development of galaxies when the universe was much younger, less than half its present age. Because the radio waves come from far away, traveling at the speed of light, they therefore represent an earlier time in the universe.
"This is what makes science so exciting," Seiffert said. "You start out on a path to measure something – in this case, the heat from the very first stars – but run into something else entirely, some unexplained."
Posted 1/15/2009 5:23 am
The cosmological constant was a fudge factor in Einstein's calculations, but there's still a good chance that dark matter/energy will fit in where Einstein left a question mark.
The current scientific consensus about the universe: It is very big, but not infinite. It's estimated to be 880,000,000,000,000,000,000,000,000 (880 x 10 to the 24) meters in diameter. It's expanding and will never stop expanding or contract again because the expansion is accelerating (nobody is sure why, but it's been measured).
Posted 1/23/2009 8:01 pm
It is practically certain that there is intelligent life elsewhere in the universe, through sheer probability.
Likewise, it is practically certain, although through sheer probability (understood best once one has a real idea of how vast the universe is, and how much of it is that said intelligent life has never, and will never, visit 'us' before we go extinct (a time period that is absurdly brief on the grand scale of time).
Posted 1/23/2009 9:59 pm
That moniker should be Admiral Oblivious. First off, nobody knows how big or small the universe is. So any probability reasoning is baseless. Furthermore, you make some contradictions. Even if hypothetically the universe was huge and nearly infinite, then the probability of them existing and having already visited us is the same as them not having existed and not having visited. Basically, there is nothing that makes it more or less probable other than maybe the size of the universe, which then makes it even less probable that they are in close proximity, or have figured out a way to travel such long distances. In other words, they likely either don't exist or already are living among us.
It's always more fun to show someone's stupidity when they're a jerk. So, off I go. :)
[quote]First off, nobody knows how big or small the universe is.
Which actually makes my point even more, because it's obvious the entire universe isn't SMALLER than the 'known universe', so if we're wrong, we're underestimating. I made my statement based on the size of the known universe; if anything, the certainty level is even higher than implied.
[quote]So any probability reasoning is baseless.
No, a definite figure is baseless. An estimate is obviously not. We have a good idea of how many stars are in just our galaxy (about 200 billion), and our little sun itself has got over half a dozen planets. Even assuming that stars have an average of one planet apiece (obvious lowballing), that means that there are about 200 billion planets in the Milky Way. Now, let's assume (in your favor, once again) that Earth is the only planet in the Milky Way with life. Even with this pair of very pessimistic assumptions, that would put the odds of a planet having life at equal to or less than 1 in 200 billion. Now let's assume there are a measly one million (our best estimate is closer to 100 BILLION) galaxies in the universe; another VERY pessimistic assumption. Even that would mean that there are at least 200 QUADRILLION planets in the universe. Even with the chance of a planet having life being 1 in 200 billion, this set dictates that a MILLION planets have life on them. Now, use realistic estimates instead of my series of lowballs and you come up with a ratio beyond human comprehension.
TL;DR --> There is more of a chance of every major lottery jackpot on earth (let's pretend they all generate six numbers) coming out with the same exact numbers on the same day than there is of Earth being the only source of life in our universe (let alone any number of other possible universes there may be that we'd probably never be able to observe at all).
[quote]Furthermore, you make some contradictions. Even if hypothetically the universe was huge
You consider it hypothetical that the universe is huge?
[quote]and nearly infinite,
Pff, I said no such thing; as I clarified already, my statement is true even based on the size of the KNOWN universe. Besides, "infinity" is mostly a philosophical concept to our brains. The universe, even just the known universe, is already massive beyond any understanding other than our abstract number system (IOW, no human can truly comprehend what a "quadrillion" is, but we can work with numbers like that in the sciences without having to). "Nearly infinite" is not even close to what would be necessary for my original statement to be true.
[quote]then the probability of them existing and having already visited us is the same as them not having existed and not having visited.
Uh, no.
[quote]Basically, there is nothing that makes it more or less probable other than maybe the size of the universe,
Wrong again. The massive amounts of energy needed for the trip are prohibitive as well. Advanced tech or not, the laws of physics set the upper bounds of speed and fuel efficiency.
[quote]In other words, they likely either don't exist or already are living among us.
What utter nonsense. I can't comprehend the level of confusion that would lead to the conclusion that THOSE are the two most likely scenarios.
I don't know what happened, but the forum ate all my closing quote tags. Do you seriously think I'd forget to close every single quote tag but the first one?
No, the best part is where dipshits like you focus on the trivial in order to escape admitting that I'm right.
The Universe does not expand, the Universe is Infinite, the planets and stars are expanding from the center of the universe outwards. The Universe does not move because it is infinite. Basic stuff here.
The Universe can't expand because it existed before there was a big bang, it's the black veil that shrouds everything.
Posted 1/25/2009 3:12 am NOTE: I know what happened now with my other post and the quote tags. If you don't include a "name" with a quote tag and just write "[quote]" instead, the forum software acts retarded and doesn't know how to deal with it. It decides to eat the closing /quote tags and just display the "[quote]" tags as-is.
The space between EVERYTHING is growing. Do you think the universe knows what a "planet" or "star" is, and makes sure the expansion happens only outside the 'jurisdiction' of a planet/star? What mechanism magically stops expansion from occurring within a planet or star's surface? FFS, you remind me of the dipshits who think it's fine and dandy that evolution can produce small changes in things, but then claim some magical barrier prevents the changes from happening on a larger scale.
Okay, let me try your logic. Claim: You're an idiot. Proof: Since you're an idiot, the stuff you do is idiotic.
Non-sequitur city. What the hell does anything in that quoted section have to do with anything else?
And "the black veil that shrouds everything?" Read less science fiction.
Once again, slowly: if the universe is 'gaining ground', it can't be infinite, or else there would be no 'ground' to 'gain' in the first fucking place.
Posted 1/25/2009 4:21 am
Nobody knows for sure. People sure like to pretend they know because idiots think that makes them smarter. Even Einstein doesn't know how big the universe is, or what it's doing. Shit, we just recently discovered that our solar system is one planet short! Fucking idiots.
In the scientific community, we are as sure the universe is expanding as we are that HIV causes AIDS. In fact, we know that the universe isn't just expanding, but that the expansion is ACCELERATING. The reason WHY that is is a big mystery currently, right past the edge of our sphere of knowledge. But THAT it's expanding? We know that as well as we can know anything.
It's through simple logic that it seems obvious that something that does (or even just something that CAN) expand, is not infinitely large. If it was infinitely large, what could it expand into?
Yes, death can have that effect on someone.
Speaking of death, Einstein died in 1955. Our technology and ability to observe 'the heavens' has progressed DRASTICALLY since then. FFS, the first computer hard drive wasn't used until 1956! Genius can only take you so far without the proper observational tools.
WTF? No, we didn't. What, do you think Pluto just ceased to exist? What we did was revise our vague definition of "planet" and split it into two categories, "planet" and "dwarf planet". Under these new categories, there are eight planets and three dwarf planets (Ceres, Eris, and Pluto) in our solar system. Which, incidentally, ties back into what I said before, which is that we're always finding MORE, not less.
Posted 1/25/2009 6:42 am
Bullshit again. The latest theory is that the universe is pulsating in size, not expanding. God you're fucking dense. You're just another tool pretending to be smarter than everyone. This is why you don't get laid.
