Gamma-ray bursts are the universe's most luminous explosions. Astronomers believe most occur when exotic massive stars run out of nuclear fuel. As a star's core collapses into a black hole, jets of material -- powered by processes not yet fully understood -- blast outward at nearly the speed of light. The jets bore all the way through the collapsing star and continue into space, where they interact with gas previously shed by the star and generate bright afterglows that fade with time.
Evidence of star birth within a cloud of primordial gas has given astronomers a glimpse of a previously unknown mode of galaxy formation. The cloud, known as the Leo Ring, appears to lack the dark matter and heavy elements normally found in galaxies today. The unexpected discovery comes thanks to instruments aboard NASA’s Galaxy Evolution Explorer (GALEX) spacecraft which are sensitive to the ultraviolet radiation emitted by newly formed stars.
I often get the query "what is a good website for astronomy?". My instant answer is "Astronomy Picture of the Day". If you're only going to check one site, choose this. One picture plus a paragraph of text each day, that's it-- simple, elegant, informative, beautiful.
If APOD piques your interest, there are good sites to go deeper. "Imagine the Universe" is a useful resource site. Don't let that Imagine lists as 'for age 14 or older' dissuade you. It's a great "facts" site, especially the "Ask an Astrophysicist" section-- full of common questions and answers delivered at a 'high layman level'. Matter of fact, years ago I contributed some of the answers.
Just a little weekend tidbit, art from the science world. Sometimes, during talks, I'll see art where others see just a data or figure. Here are two cases from a recent conference that I love.
This one could be called "Relationship between a CME-driven shock and a coronal metric type II burst", excerpted, from Y. Liu. But I prefer to call it 'sunset on the sea':
If you click on the image, you can see the full data plot, taken (without forewarning to the scientists) from their online powerpoint slides.
One of my readers (via Facebook) said he loved my blog but still had no idea what I did. Good point. While most career scientists hyperspecialize, I've moved among multiple fields of astronomy, often confusing myself in the process.
Currently, I create computer simulations of the sun to understand and enable prediction of the brief but potent solar eruptions that can kill cellphones, GPS and airline pilots. For those in the field, I say I study coronal mass ejections (CMEs) using data from the NASA STEREO satellites.
Scientists have used a computer simulation to predict what the very early Universe would have appeared like 500 million years after the Big Bang. The images, produced by scientists at Durham University's Institute for Computational Cosmology, show the "Cosmic Dawn" - the formation of the first big galaxies in the Universe.Universe 590 million years after the Big Bang. Credit:Alvaro Orsi, Institute for Computational Cosmology
The recent video "Barriers to Innovation" has some great thoughts about the culture of NASA and its barriers to innovation. Arriving from a Johnson Space Center study, the 10 minute video
is worth a look.
Ultimately, yes, I wish NASA had more of a mad scientist component. I think they're risk averse because that's part of their mandate. Google's founders gave Google "do no evil". Congress gave NASA "don't screw up".
I gave a talk on my dissertation work. Several of the more senior scientists were amazed at the bonafide science it contained. They'd had me pinned as someone who did 'service work'-- programming, project management, all the stuff that enables science for others (them). This is the kiss of death to scientific collaboration. Once you're marked with the taint of 'service', everyone assumes you're a scientific moron.
You can tell the difference in how they explain something. If you're a service person, they give you analogies ("imagine if..."). If they see you as a fellow scientist, they go right to authors and citations so you can read the original paper.
Neither approach is particularly efficient.
We had an exciting two hours back when the STEREO solar telescope satellites were first launched. The first summed image of several hours of first-light data showed a clear distortion in one of the ten SECCHI detectors. Doom! Tragedy! Can we compensate for it?
It was almost like the sky was a bathtub draining to the lower left. All the light warped and bended in that direction. Opinions varied as to the cause... was it a bad CCD, misalignment of the scope, or satellite pointing issue? Was that detector totally FUBARed? Could it be saved!?!?!
An unusual spiral galaxy in the Coma galaxy cluster has been imaged using data obtained by the Advanced Camera for Surveys on the Hubble Space Telescope. It reveals fine details of the galaxy, NGC 4921, and an extraordinary rich background of more remote galaxies stretching back to the early Universe.
The Coma galaxy cluster, in the northern constellation of Coma Berenices, the hair of Queen Berenice, is one of the closest, very rich collections of galaxies in the nearby Universe. The cluster, also known as Abell 1656, is about 320 million light-years from Earth and contains more than 1000 members. The brightest galaxies, including NGC 4921 shown here, were discovered back in the late 18th century by William Herschel.