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Most Distant Object Yet Detected, Bagged By Galileo Scope
An anonymous reader writes "It's fitting, in this 400th anniversary of the astronomical telescope, that the Telescopio Nationale Galileo (TNG) in the Canary Islands would be used to uncover the most distant object ever seen by mankind. The gamma-ray burst from April 23, a powerful explosion from a dying star, was detected by the Swift satellite using on-board gamma-ray and X-ray instruments. A flurry of activity led to the remarkable discovery that the event occurred roughly 630 million years after the Big Bang. This makes GRB 090423 the most distant known event!"
After the Big Bang... comes the Big Cigarette.
correct Italian spelling: "Telescopio Nazionale Galileo" (not 'Telescopio Nationale Galileo' as written in the story blurb)
Also, it probably was very weak in heavier elements, so it would have been a very pure collection of hydrogen. So, we're looking at a pretty "pure case" of massive star formation, fuel burning and some kind of hypernova.
This is really interesting stuff.
RS
Shoes for Industry. Shoes for the Dead.
Everyone knows the Earth and therefore the Universe is only 6,000 years old.
This happened billions of years ago, and Slashdot is just reporting it now?
"It's fitting, in this 400th anniversary of the astronomical telescope, that the Telescopio Nationale Galileo (TNG) in the Canary Islands would be used to uncover the most distant object ever seen by mankind.
It's fitting in a numerological sort of way... I'm sure that any day you'd care to pick out in the year could be linked to some date in the past that is also connected with some event in the field of astronomy, whether it be the birthday of a famous astronomer, the discovery of a moon, an extra-solar planet, the day Voyager started photographing or stopped photographing a planet...
Sorry to be an old grump.... Perhaps it's simply because I found out a very cute girl I know thinks numerology is anything more than utter nonsense and I want better genes for my children...
You can see as far back (in light) as the time when the universe was last opaque. This (approximately the same distance from us in all directions, thus forming a sphere) is called the surface of last scattering.
At the time of and before last scattering (approx. 400,000 years after the Big Bang, if our cosmological theories are reasonably close to correct), light was constantly being absorbed and reemitted, as in the interior of a star today. If you suddenly removed all the matter from a star (obviously impossible, but bear with me here), then the photons that had last been emitted would travel off in all directions.
The universal last scattering was a vaguely similar event, in that matter became sufficiently dispersed (due to the expansion of the universe) that light could now travel long distances without interacting with matter. Obviously this was not instantaneous, but on cosmological scales, it was pretty quick.
Now, an object that is at a certain temperature will in general radiate a certain amount of light, distributed in a very particular way over a range of frequencies. For instance, the temperature of the Sun's photosphere (which is about as far into the Sun as you can get and still have the gases be reasonably transparent, thus, it is the Sun's surface of outermost scattering, one might say) almost determines the spectrum of light that the Sun emits, and therefore the color that we see (yellow). This is called blackbody radiation.
So, the universe at the time of last scattering contained a gas of photons with a certain spectrum determined by the overall temperature of the universe then. When the universe became transparent, this photon gas remained, and remained at the same spectrum. It still permeates the entire universe. However, due to the expansion of the universe, the wavelength of each and every photon has increased since then, and the density of photons has decreased, leading to a photon gas that looks as if it comes from a much cooler object. In fact, now the largest number of the photons in the universe lie in the region of the spectrum designated "micro-waves", thus we refer to this leftover photon gas as the cosmic microwave background.
The CMB was a direct prediction of Big Bang cosmological models, and not a prediction of any other cosmological models, and so its observation dealt a death blow to other models such as the steady state universe.
SIGSEGV caught, terminating
wait... not that kind of sig.
The decoupling of matter and radiation is an extremely interesting event that happened 400,000 years after the big bang. Its nature makes it the oldest possible observable event, and interestingly enough, thanks to experiments as COBE and WMAP we have very pretty pictures of that event.
Congrats to the scientists!
The most distant object I've ever observed was on an astronomy trip to Costa Rica in February. I had set myself the challenge of sighting the nearest star in the night sky (Alpha Centauri C, aka Proxima Centauri), and the most distant object visible in all but the largest amateur-size telescopes, the quasar 3C273.
I nailed them both in a single night with patience, finder charts and an 8" Schmidt-Cassegrain. 4.2 light years and 2.5 to 3 billion, depending on which reference you use. Proxima is in a cluttered Milky Way field, while 3C273 appears to form a double star with a star in the Milky Way, not far from Gamma Virginis.
...laura
Too bad not one article said how distant it was. Still working on that one, but at least we know it's the "most" distant.