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The most distant object you could see with the naked eye...
sataicallista
High Priestess of Squeee!
in Zocalo v2.0
...was visible a few days ago to those who were looking in the right place at the right time. [URL="http://science.nasa.gov/headlines/y2008/21mar_nakedeye.htm"]A massive and incredibly old gamma ray burst.[/URL] The link actually has a movie of it, but here's the text for the lazy people:
March 21, 2008: A powerful gamma ray burst detected March 19th by NASA's Swift satellite has shattered the record for the most distant object that could be seen with the naked eye.
"It was a whopper," says Swift principal investigator Neil Gehrels of NASA's Goddard Space Flight Center. "This blows away every gamma ray burst we've seen so far."
Swift's Burst Alert Telescope picked up the burst at 2:12 a.m. EDT on March 19, 2008, and pinpointed the coordinates in the constellation Bootes. Telescopes in space and on the ground quickly moved to observe the afterglow. The burst was named GRB 080319B and registered between 5 and 6 on the visual magnitude scale used by astronomers. (A magnitude 6 star is the dimmest visible to the human eye; magnitude 5 is almost three times brighter.)
Later that evening, the Very Large Telescope in Chile and the Hobby-Eberly Telescope in Texas measured the burst's redshift at 0.94. A redshift is a measure of the distance to an object. A redshift of 0.94 translates into a distance of 7.5 billion light years, meaning the explosion took place 7.5 billion years ago, a time when the universe was less than half its current age and Earth had yet to form. This is more than halfway across the visible universe.
"No other known object or type of explosion could be seen by the naked eye at such an immense distance," says Swift science team member Stephen Holland of Goddard. "If someone just happened to be looking at the right place at the right time, they saw the most distant object ever seen by human eyes without optical aid."
Most gamma ray bursts occur when massive stars run out of nuclear fuel. Their cores collapse to form black holes or neutron stars, releasing an intense burst of high-energy gamma rays and ejecting particle jets that rip through space at nearly the speed of light. When the jets plow into surrounding interstellar clouds, they heat the gas to incandescent visibility. It is this gaseous "afterglow" which was visible to the human eye on March 19th.
GRB 080319B's afterglow was 2.5 million times more luminous than the most luminous supernova ever recorded, making it the most intrinsically bright object ever observed by humans in the universe. The most distant previous object that could have been seen by the naked eye is the nearby galaxy M33, a relatively short 2.9 million light-years from Earth.
Analysis of GRB 080319B is just getting underway, so astronomers don't know why this burst and its afterglow were so bright. One possibility is the burst was more energetic than others, perhaps because of the mass, spin, or magnetic field of the progenitor star or its jet. Or perhaps it concentrated its energy in a narrow jet that was aimed directly at Earth.
GRB 080319B was one of four bursts that Swift detected on March 19th, a Swift record for one day. Swift science team member Judith Racusin of Penn State University comments, "coincidentally, the passing of Arthur C. Clarke seems to have set the universe ablaze with gamma ray bursts." A fitting farewell, indeed.
March 21, 2008: A powerful gamma ray burst detected March 19th by NASA's Swift satellite has shattered the record for the most distant object that could be seen with the naked eye.
"It was a whopper," says Swift principal investigator Neil Gehrels of NASA's Goddard Space Flight Center. "This blows away every gamma ray burst we've seen so far."
Swift's Burst Alert Telescope picked up the burst at 2:12 a.m. EDT on March 19, 2008, and pinpointed the coordinates in the constellation Bootes. Telescopes in space and on the ground quickly moved to observe the afterglow. The burst was named GRB 080319B and registered between 5 and 6 on the visual magnitude scale used by astronomers. (A magnitude 6 star is the dimmest visible to the human eye; magnitude 5 is almost three times brighter.)
Later that evening, the Very Large Telescope in Chile and the Hobby-Eberly Telescope in Texas measured the burst's redshift at 0.94. A redshift is a measure of the distance to an object. A redshift of 0.94 translates into a distance of 7.5 billion light years, meaning the explosion took place 7.5 billion years ago, a time when the universe was less than half its current age and Earth had yet to form. This is more than halfway across the visible universe.
"No other known object or type of explosion could be seen by the naked eye at such an immense distance," says Swift science team member Stephen Holland of Goddard. "If someone just happened to be looking at the right place at the right time, they saw the most distant object ever seen by human eyes without optical aid."
Most gamma ray bursts occur when massive stars run out of nuclear fuel. Their cores collapse to form black holes or neutron stars, releasing an intense burst of high-energy gamma rays and ejecting particle jets that rip through space at nearly the speed of light. When the jets plow into surrounding interstellar clouds, they heat the gas to incandescent visibility. It is this gaseous "afterglow" which was visible to the human eye on March 19th.
GRB 080319B's afterglow was 2.5 million times more luminous than the most luminous supernova ever recorded, making it the most intrinsically bright object ever observed by humans in the universe. The most distant previous object that could have been seen by the naked eye is the nearby galaxy M33, a relatively short 2.9 million light-years from Earth.
Analysis of GRB 080319B is just getting underway, so astronomers don't know why this burst and its afterglow were so bright. One possibility is the burst was more energetic than others, perhaps because of the mass, spin, or magnetic field of the progenitor star or its jet. Or perhaps it concentrated its energy in a narrow jet that was aimed directly at Earth.
GRB 080319B was one of four bursts that Swift detected on March 19th, a Swift record for one day. Swift science team member Judith Racusin of Penn State University comments, "coincidentally, the passing of Arthur C. Clarke seems to have set the universe ablaze with gamma ray bursts." A fitting farewell, indeed.
Comments
You obviously don't understand lazy people. :D
They don't want to read. They'll click the link and watch the movie... if they feel like it. :D
As for the gamma ray burst, it's like a tree falling in the woods.
These appear to be very old events, do they still happen in astronomicaly recent times?
I've seen shooting stars in the night sky and they go by so fast, you barely have time to focus on them.
It's good to know someone's watching the sky though. :D
[QUOTE=JackN;171191]Just out of curiosity, what is the youngest Gamma Ray burst ever detected?
These appear to be very old events, do they still happen in astronomicaly recent times?[/QUOTE]
Swift has apparently detected one about 440 million light years away, which is pretty recent.
What I do find comforting is the thought that the universe is so huge and probably full of life. Since we are made of star dust, there's plenty more from where that came from. :D
What I do find comforting is the thought that the universe is so huge and probably full of life. Since we are made of star dust, there's plenty more from where that came from. :D[/QUOTE]
5.865 [B]trillion[/B] miles. It's fairly easy, too. Light travels at 186,000 miles per second/299,792,458 meters per second. There are 86,400 seconds in a day (60 seconds in a minute, 60 minutes in an hour, 24 hours in a day) and 365 (ish) days in a year. If we so want to call it a leap year, then your results will vary. :p 31,536,000 seconds in a year multiplied by 186,000 miles/second leaves you with 5,865,696,000,000 miles/year. Assuming a direct path was taken and that the light wasn't bowed around some gravitational lens and you can pretty much figure out the rest.
Duh.
(Psst, it's 2,580,906,240,000,000,000,000 miles...)
I also have to laugh at the term, big bang. It was anything but a big bang. There is no word to describe what really happened. I mean the scale of it... but it must have been very quiet, violent, but very quiet... and I wonder if anybody was there to see it.
I also can't put my head around what happened before the big bang, the big badaboom. There is always a BOOM! :D
I'm going to sleep now and get my head around a pillow now. :D
[QUOTE=Sanfam;171202]5.865 [B]trillion[/B] miles.[/QUOTE]
Or, for those of us who don't live in one of [url=http://en.wikipedia.org/wiki/Image:Metric_system.png]only three countries on the planet[/url] still using imperial units, 9,460,730,472,580.8km. :p
Or, for those of us who don't live in one of [url=http://en.wikipedia.org/wiki/Image:Metric_system.png]only three countries on the planet[/url] still using imperial units, 9,460,730,472,580.8km. :p[/QUOTE]
It's called the "Coalition of the Willing...and a couple other guys!"
Big Expansion?
The part that always warps my mind is the fact that the further the event/object is from us the older the event object is/was. Some things that we are seeing now don't even exist anymore.
I agree, and that rogue galaxy that is currently "frying" another galaxy with its own black hole that is spewing IIRC gamma radiation is also quite dramatic. Who knows how many civilizations are being eliminated as this is happening? You can't make this stuff up, looking at the stars sure beats scifi any day.
Of course, that's not recent though, right? It happened a long time ago since we're just seeing this.
Well, given the size of galaxies, and the nature of the event, this collision between those two galaxies must have taken a very long time.
It is true that the way we see galaxies now, is not the way they are right now.
So you are right in that this is an old event, yet, depending on the motions of both galaxies, they may have both moved on separately or merged to become one, with the first having sterilized the second.
On the scale of galaxies, space is sparkling with activity. To us all seems to be in a perpetual frozen state. :D
Or someone pulled of God's finger
I think there is a grand designer. time will tell.
[url]http://en.wikipedia.org/wiki/Omega_Point[/url]
I lost the original source, but it was in the news like 2 months ago. The blue plume is what is causing the damage.
I kept this image because I thought it was quite fascinating.
Must be my pension .. :D
Close or recent ones, only if they're pointed elsewhere.
[QUOTE=Stingray;171311]Here's the image of the [URL="http://i3.photobucket.com/albums/y79/stingray_b5/rogue_galaxy_800x600.jpg"]rogue galaxy[/URL].
I lost the original source, but it was in the news like 2 months ago. The blue plume is what is causing the damage.
I kept this image because I thought it was quite fascinating.[/QUOTE]