Mystery Roar from Faraway Space Detected

[JPetrillo]

Weird!!

http://www.space.com/scienceastronom...mic-noise.html

LONG BEACH, Calif. -- 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."

[RockStar]

The universe is a strange place indeed...

[JayMac743]

If a tree fell in the woods, and no one was there to hear it, did it make noise??


Thats a good read, makes me wonder whats REALLY out there.....

[LostSoul]

Originally Posted by iiijay743iii

If a tree fell in the woods, and no one was there to hear it, did it make noise??

If nobody heard it, it never did.

According to Definition of Sound, No.

According to Merriam-Webster, sound is the sensation perceived by the sense of hearing. So that means that vibrating air is just that, mechanical vibrations of air molecules. When those vibrations are perceived by the sense of hearing, then they become a sensation; the sensation of sound. That is why we have an auditory cortex in the neocortex of the brain that interprets those vibrations as a tree falling, a bird singing, or the wind whistling through the leaves.

Here is an example: If you never heard a tree fall as it crashed to the ground and you were standing in the woods blindfolded as one fell, you would hear noise. The noise would be the vibrations in the air of the tree hitting the ground. Most likely you would hear something, but you would not know what it was. But, if you had heard enough similar noises before, your brain would then be able to identify the vibrations as being produced by a tree falling. Then it would be a sound. So, going by the Merriam-Webster definition, the tree would make air molecules vibrate, but would not make a 'sound' if it fell in the woods and nobody was there to hear it.

[JPetrillo]

Check out this video:



...interesting stuff.

[hotaruharu]

Originally Posted by iiijay743iii

If a tree fell in the woods, and no one was there to hear it, did it make noise??


Thats a good read, makes me wonder whats REALLY out there.....

why, there be dragons, of course.

[JPetrillo]

Just FYI: It doesnt actually make a "noise"...

When the tree falls and it finally makes impact with the ground a vibration forms (in the same way ripples form when a rock is thrown into still water). This vibration sets out from all directions of the point of impact. If there is a living being within the range that the vibration can travel, it will then be interpreted as a noise. If there is no living being within the distance the vibration can travel, it will not be interpreted as a "noise". To be a noise it must first be experienced/perceived. So the new question is, "If a vibration is caused by something in the woods and no one can hear or feel it, is it real?" Okay, the only real answer to any metaphysical questions such as these is that consciousness makes the sound into how it will be perceived. Without consciousness the vibration could not be interpreted as a sound. Your conscious thought (the voice in your head asking this question) was the answer to the question all along.

[LostSoul]

NASA is gonna go up there and figure it out now. They just launched the Discovery yesterday... perfect launch