Oldest, Most Distant Object Ever Detected
Yousuf Khan
http://www.theaustralian.news.com.au/story/0,25197,25403253-12377,00.html
Tue Apr 28 2009 22:39:48 GMT-0400 (Eastern Daylight Time)
ASTRONOMERS have spied a gamma-ray burst from the universe's infancy,
making it the oldest event ever witnessed and shedding light on cosmic
origins.
"This is the most remote gamma-ray burst ever detected, and also the
most distant object ever discovered - by some way,'' Nial Tanvir at
Britain's University of Leicester said.
Gamma-ray bursts, the universe's most luminous explosion, happen when
massive stars run out of nuclear fuel.
Their cores collapse into a black hole or neutron star, and gas jets, in
a process still not fully understood, punch out in a spectacular surge
into space.
The so-called "GRB 090423'' explosion, which occurred when the universe
was only 640 million years old - some five per cent of its current age -
was seen by the NASA Swift satellite on April 23.
Subsequent analysis by teams of scientists, utilising the European
Southern Observatory's Very Large Telescope in Chile, showed the
satellite effectively looked back in time 13 billion years.
"Swift was designed to catch these very distant bursts,'' Swift lead
scientist Neil Gehrels at NASA's Goddard Space Flight Centre in Maryland
said.
"We've waited five years, and we finally have one.''
The event's capture has the potential of illuminating astronomy in its
quest to unravel the mysteries of the early universe.
"At its most basic level this discovery tells us that there were massive
stars at this moment in cosmic history,'' Andrew Levan at Britain's
University of Warwick said.
"But equally importantly we can use events like this to probe how the
universe evolves when it is less than five per cent of its current age.''
Sam Wormley
http://www.sciencenews.org/view/generic/id/43268/title/Most_distant_known_object_in_the_universe
Astronomers have discovered a gamma-ray burst emanating 13.035 billion light-years from
Earth, making it the universe's most distant known object.
Sam Wormley
Dave Typinski wrote:
> What happened to Abell 1835 IR1916?
> --
> Dave
Good Question!
http://en.wikipedia.org/wiki/Abell_1835_IR1916
"... further analysis by Weatherley, Warren and Babbedge (2004) of the
data that led to the first announcement has cast doubt on the claim
that it is a distant object, and follow-up observations in the H-band
using the Gemini North Telescope (Bremer et al. 2004) and observations
from the orbiting Spitzer Space Telescope (Smith et al. 2006) were not
able to detect it at all".
jesko
> GRB 090423 explosion '13 billion years old' | The Australianhttp://www.theaustralian.news.com.au/story/0,25197,25403253-12377,00....
Is it possible in a future time to make a photo to BigBang explosion?
BigBang explosion light is travelling toward us and so...
Sam Wormley
>
> Is it possible in a future time to make a photo to BigBang explosion?
> BigBang explosion light is travelling toward us and so...
>
No Center
http://www.astro.ucla.edu/~wright/nocenter.html
http://www.astro.ucla.edu/~wright/infpoint.html
Also see Ned Wright's Cosmology Tutorial
http://www.astro.ucla.edu/~wright/cosmolog.htm
http://www.astro.ucla.edu/~wright/cosmology_faq.html
http://www.astro.ucla.edu/~wright/CosmoCalc.html
WMAP: Foundations of the Big Bang theory
http://map.gsfc.nasa.gov/m_uni.html
WMAP: Tests of Big Bang Cosmology
http://map.gsfc.nasa.gov/m_uni/uni_101bbtest.html
YKhan
> Is it possible in a future time to make a photo to BigBang explosion?
> BigBang explosion light is travelling toward us and so...
There is one limit to how far back you can go. That limit is called
the Cosmic Microwave Background Radiation. That's supposed to be as
far back as you can see before which it's all blank. The CMBR is
supposed to have lasted upto 300,000 years after the Big Bang, so we
should not be able to see through the fog to the BB itself.
However, if we do see something that has a red-shift that goes back
before the CMBR, then all hell will break loose. It could mean one of
several things: (1) red shifts don't represent time and distance, (2)
the CMBR wasn't at 300,000 years after BB but possibly earlier, (3)
the CMBR might not be as opaque as they thought, or (4) there were
stars, galaxies and stuff before the CMBR, etc.
Yousuf Khan
Sam Wormley
> On Apr 29, 4:08 am, jesko <frans...@gmail.com> wrote:
>> Is it possible in a future time to make a photo to BigBang explosion?
>> BigBang explosion light is travelling toward us and so...
>
> There is one limit to how far back you can go. That limit is called
> the Cosmic Microwave Background Radiation. That's supposed to be as
> far back as you can see before which it's all blank. The CMBR is
> supposed to have lasted upto 300,000 years after the Big Bang, so we
> should not be able to see through the fog to the BB itself.
Background on the CMB
http://en.wikipedia.org/wiki/Cosmic_microwave_background_radiation
We might be able to see further back than 380,000 after the BB via
neutrinos and/or or gravity waves.
There is a tremendous amount of information encoded in the CMB.
No Center
http://www.astro.ucla.edu/~wright/nocenter.html
http://www.astro.ucla.edu/~wright/infpoint.html
Also see Ned Wright's Cosmology Tutorial
http://www.astro.ucla.edu/~wright/cosmolog.htm
http://www.astro.ucla.edu/~wright/cosmology_faq.html
http://www.astro.ucla.edu/~wright/CosmoCalc.html
WMAP: Foundations of the Big Bang theory
http://map.gsfc.nasa.gov/m_uni.html
WMAP: Tests of Big Bang Cosmology
>
Sam Wormley
>
> However, if we do see something that has a red-shift that goes back
> before the CMBR, then all hell will break loose. It could mean one of
> several things: (1) red shifts don't represent time and distance, (2)
> the CMBR wasn't at 300,000 years after BB but possibly earlier, (3)
> the CMBR might not be as opaque as they thought, or (4) there were
> stars, galaxies and stuff before the CMBR, etc.
>
> Yousuf Khan
The CMB starts about 380,000 year after the BB when the universe
cooled enought for matter and energy (electromagnetic) to decouple.
The fist stars turn on about a thousand times further down the
road at about 400,000,000 years after the BB.
http://antwrp.gsfc.nasa.gov/apod/ap060323.html
Yousuf Khan
Well, that would mean we shouldn't see the earliest stars before 13.2 or
13.3 billion years ago. The GRB just witnessed was a Type Ic supernova
in the region of 13.0 to 13.1 billion years ago. Type Ic supernovas go
supernova by themselves without requiring aid from a nearby companion.
But since we do cosmological speed and distance calibrations based on
Type Ia supernovas, what's the earliest time we should be able to see a
Type Ia supernova? We'd have to assume the most optimal star that can go
from main sequence to white dwarf in the fastest possible time, and then
have a companion to siphon gas off in the fastest possible time, so that
it can go supernova.
Yousuf Khan
Sam Wormley
Since Type Ia supernovae involve white dwarfs and the main sequence
lifetime of the most massive stars that end up as white dwarfs can
be as short as 2 x 10^7 years, one would think that Type Ia supernovae
light goes back pretty close to early star formation.
Yousuf Khan
> Since Type Ia supernovae involve white dwarfs and the main sequence
> lifetime of the most massive stars that end up as white dwarfs can
> be as short as 2 x 10^7 years, one would think that Type Ia supernovae
> light goes back pretty close to early star formation.
So 20 million years is fastest you can go to white dwarf. What's the
quickest it can ingest material from a companion to go supernova? Is
there any rules about that?
I suppose a white dwarf could somehow spiral right into a companion and
it'll go supernova in an instant then, taking both stars with it. Or
would that even be considered a Type Ia? The nuclear furnace of the
companion would add more power to that explosion.
Yousuf Khan
Sam Wormley
Once that degenerate white dwarf exceeds the Chandrasekhar limit... Kablooie!