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Brian Grefenstette
Works at California Institute of Technology
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Brian Grefenstette

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A new image of M7 shows stars shining like diamonds in the tail of Scorpius. The star cluster is about 200 million years old and a part of its population are expected to explode as supernovas.
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Brian Grefenstette

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(Full disclosure, this is my work!!)
 
One of the biggest mysteries in astronomy, how stars blow up in supernova explosions, is unraveling thanks to new data from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR. In this image of Cassiopeia A, NuSTAR data, which show high-energy X-rays from radioactive material, are colored blue. Lower-energy X-rays from non-radioactive material are shown in red, yellow and green. Cassiopeia A is the remains of a star that blew up in a supernova event whose light reached Earth about 350 years ago, when it could have appeared to observers as a star that suddenly brightened. The remnant is located 11,000 light-years away from Earth.

When massive star explode, they create many elements: non-radioactive ones like iron and calcium found in your blood and bones; and radioactive elements like titanium-44, the decay of which sends out high-energy X-ray light that NuSTAR can see. By mapping titanium-44 in Cassiopeia A, astronomers get a direct look at what happened in the core of the star when it was blasted to smithereens. The fact that the titanium -- which is a direct tracer of the supernova blast -- is concentrated in clumps at the core supports a theory referred to as "mild asymmetries." In this scenario, material sloshes about at the heart of the supernova, reinvigorating a shock wave and allowing it to blow out the star's outer layers.

Image credit: NASA/JPL-Caltech/CXC/SAO

#nasa #star #supernova #nustar #space #science #titanium #cassiopeia

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See, I've been absent from G+ for a good reason…check out the uStream tomorrow morning!
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Atoms, the building blocks of matter, are constantly in motion, moving around at speeds that are thousands of miles per hour at room temperatures, and millions of miles per hour behind a supernova shock wave.

In a collision of an atom with another atom, or with a free-roaming electron, energy can be transferred to the atom. This extra energy can then be released in the form a light wave.

Download and print your own version here: http://hte.si.edu/multimedia.html

#HTEscience
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that's GREAT ! lol
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Have him in circles
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Brian Grefenstette

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Untangling the Remains of Cassiopeia A | NASA Chandra
The mystery of how Cassiopeia A exploded is unraveling thanks to new data from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR. In this image, NuSTAR data, which show high-energy X-rays from radioactive material, are colored blue. Lower-energy X-rays from non-radioactive material, imaged previously with NASA's Chandra X-ray Observatory, are shown in red, yellow and green.

The new view shows a more complete picture of Cassiopeia A, the remains of a star that blew up in a supernova event whose light reached Earth about 350 years ago, when it could have appeared to observers as a star that suddenly brightened. The remnant is located 11,000 light-years away from Earth.

NuSTAR is the first telescope capable of taking detailed pictures of the radioactive material in the Cassiopeia A supernova remnant. While other telescopes have detected radioactivity in these objects before, NuSTAR is the first capable of pinpointing the location of the radioactivity, creating maps. When massive star explode, they create many elements: non-radioactive ones like iron and calcium found in your blood and bones; and radioactive elements like titanium-44, the decay of which sends out high-energy X-ray light that NuSTAR can see.

By mapping titanium-44 in Cassiopeia A, astronomers get a direct look at what happened in the core of the star when it was blasted to smithereens. These NuSTAR data complement previous observations made by Chandra, which show elements, such as iron, that were heated by shock waves farther out from the remnant's center.

In this image, the red, yellow and green data were collected by Chandra at energies ranging from 1 to 7 kiloelectron volts (keV). The red color shows heated iron, and green represents heated silicon and magnesium. The yellow is what astronomers call continuum emission, and represents a range of X-ray energies.

The titanium-44, shown in blue, was detected by NuSTAR at energies ranging between 68 and 78 keV.

The NuSTAR observations point to a possible solution to the puzzle of how stars detonate. The fact that the titanium -- which is a direct tracer of the supernova blast -- is concentrated in clumps at the core supports a theory referred to as "mild asymmetries." In this scenario, material sloshes about at the heart of the supernova, reinvigorating a shock wave and allowing it to blow out the star's outer layers.

NuSTAR is a Small Explorer mission led by the California Institute of Technology in Pasadena and managed by NASA's Jet Propulsion Laboratory, also in Pasadena, for NASA's Science Mission Directorate in Washington. The spacecraft was built by Orbital Sciences Corporation, Dulles, Va. Its instrument was built by a consortium including Caltech; JPL; the University of California, Berkeley; Columbia University, N.Y.; NASA's Goddard Space Flight Center, Greenbelt, Md.; the Danish Technical University in Denmark; Lawrence Livermore National Laboratory, Livermore, Calif.; ATK Aerospace Systems, Goleta, Calif., and with support from the Italian Space Agency (ASI) Science Data Center, Rome, Italy.

NuSTAR's mission operations center is at UC Berkeley, with ASI providing its equatorial ground station located at Malindi, Kenya. The mission's outreach program is based at Sonoma State University, Rohnert Park, Calif. NASA's Explorer Program is managed by Goddard. JPL is managed by Caltech for NASA.

Credit: NASA/JPL-Caltech/CXC/SAO 

+NASA Jet Propulsion Laboratory +NASA Goddard 

#NASA   #Astronomy  #Star #Supernova #Remnant #Chandra #Cassiopei #NuSTAR #Xray #Universe #Cosmos
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Brian Grefenstette

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Check it out this morning!
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Chandra Flashback of the Day – Abell 1758: Cluster Collisions Switch on Radio Halos 
http://chandra.harvard.edu/photo/2010/a1758/
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Stellar Shrapnel Seen in Aftermath of Explosion
http://chandra.si.edu/photo/2010/n49/

This composite image of data from Chandra (blue) and Hubble (yellow and purple) depicts the scene of a supernova explosion's aftermath. The X-ray data reveal a bullet-like structure to the lower right that appears to have been blown out of the remnant. The detection of the bullet, which is traveling at some 5 million miles per hour, is evidence that the explosion that created the remnant was not symmetrical.
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Have him in circles
12,910 people
Education
  • Stanford University
    Physics, 2000 - 2004
  • University of California, Santa Cruz
    Physics, 2004 - 2008
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Scientist
Employment
  • California Institute of Technology
    Staff Scientist, 2012 - present
    I'm a principle mission scientist on a NASA Small Explorer mission, the Nuclear Spectroscopic Telescope ARray (NuSTAR), the world's first focusing hard X-ray telescope. I "do science" (I mostly study supernova remnants like Cassiopeia A) now that NuSTAR is up in space, but I also help to develop and maintain the software down here on the ground that turns the bits and bytes coming down from NuSTAR into pictures and spectra.
  • California Institute of Technology
    Postdoc, 2008 - 2012
  • University of California, Santa Cruz
    Research Assistant, 2004 - 2008
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