Zooming in on Universe's First Starlight: "Everything Else Came After This"

Scientists have seen the first starlight ever recorded, and we don't mean the first incidence of a monkey marking something down - we mean the first star to send light which reached Earth.  This light is the earliest, the furthest away, the most red-shifted, and every other factor that could possibly say "Everything else ever came after this."

The bright light is also poignant as it results from a Gamma Ray Burst, GRB 090423, meaning that this first light comes from the death of a star imploding into a neutron star or even an early black hole.  The light exhibited a record breaking redshift of 8.2, the electromagnetic equivalent of an ambulance's siren sounding lower pitched because it's moving away from you.  Now ramp up that ambulance close to the speed of light, turn it into an exploding sun, put it on the opposite end of the observable universe and - while you're at it - stick it at the beginning of time.

The event occurred when the universe was only half a billion years old and the light has literally spent all of time to get here.  The signal was detected by the Swift Gamma-Ray Burst Mission, and a good thing too - can you imagine coming all that way and not being seen?  The starburst was so early it was used to confirm that this kind of thing even happened back then.  The signal outshone galaxies, and is now our earliest evidence of anything that happened back then.

Think about that while you surf Twitter.

http://news.yahoo.com/s/nm/20091029/sc_nm/us_star

Comments

[Narendra Nath]

If that is true then it is the first ever cosmological study of the oldest star in the universe. Nothing has yet beeen reported from a time as far back as 13.2 billion years ago. Any special report on the findings from this study, i am keen to know.

[Barrie O'Leary]

Well, Mr. Nath, consider yourself as being informed. I would consider it to have been a supermassive star to have formed and
detonated all within only 500 million years. It must have formed a black hole which,who knows, has gone on to amalgamate into a galaxy. Could there have been galaxies then? The article intimates such by mentioning that the supernova outshone all galaxies. But I find it intriguing that this event could probably have occurred before life could have emerged anywhere in the entire cosmos.

But please, for amateurs like me, what does a redshift of 8.2 equate to in lightyear speed? I have a sneaking suspicion that it is even greater than c. That would create some interesting discussion.

[xhiwas]

How come it reached us after 13 billion years if we didn't exist yet? If a photon of that light traveled 13 billions years to reach our eyes, how do we were here to get it if that light was the first thing to get to this point of the space? Only if the star has kept shining for 13 billions years that could be possible, but I don't think a star can shine for that long. Even more, that would mean that the Universe is way more old that the 13-15 billions years the scientists say it is, because matter has to have been traveling at a very lower speed that light to get to this point of the space. Also, if the star is 13 billion years apart of Earth, why the Universe has to be 13-15 billons year old? That would be only if we were at one extreme of the Universe and the star at the other, but cosmology tells us that the our solar system and our galaxy are surrounded by multiple galaxies at every direction. Moreover, it's impossible that the Universe can have a length measured by the light and shining of stars if matter travels at very low speed.

[kyle]

xhiwas: first ever recorded, not necessarily first ever. the wording is a bit confusing, but there would be no way to know it was actually the first - only that it is the first we have recorded.

[Prometheus]

o'Leary: Red-shift isn't a speed, it's the shifting of frequencies of light based on how the source is moving relative to the observer. Since the universe is expanding, everything is moving away from everything. Any light that reaches us undergoes a certain amount of red-shifting, or the shifting of the frequencies of light to the lower frequencies. The longer the time the light travels, the more shifting it experiences. The farther away a light source is, the longer it has to travel to get to Earth. So, the farther away the light is, the more red-shifting occurs. By measuring the amount the light has red-shifted, we can pin point with reasonable accuracy how far, and thus, how old, the source is.

xhiwas: You misunderstand the wording. All light travels through space at the same speed: The speed of light in a vacuum, c. Thus, if a source of light is 13.2 billion light years away, it will take light 13.2 billion years to travel the distance between the source and Earth (a light year is the distance light travels in a year). This means that when the universe was 500 million years old, this star exploded and sent high energy photons shooting toward the Earth. Because the Earth is 13.2 billion light years away, it took this light 13.2 billion years to get here, the farthest distance any light has traveled according to records, and thus the oldest light recorded, and thus the first light emitted by a star as per our records.