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CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
BLACK HOLE FIRES ATNEIGHBORING GALAXY BLACK HOLE FIRES ATNEIGHBORING GALAXY
Dr. Dan EvansNASA’s Chandra X-ray ObservatoryHarvard-Smithsonian Center for Astrophysics
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
CHANDRA: NOT YOUR BACKYARD TELESCOPE
Most people think of a “telescope” as
something in a backyard or the dome at
the local planetarium. But telescopes
like these that detect the kind of light
we can see with our human eyes are
just one answer. Stopping there would
be like saying, we have cars to get
around, who needs airplanes?
Light takes on many forms — from
radio to infrared to X-rays and more.
And the Universe tells its story through
all of these different types of radiation.
So, in order to really understand the
cosmos, astronomers need all different
kinds of telescopes.
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
THE BIG PICTURE
Do we really need these “other” kinds of telescopes? The truth is if we only studied
the cosmos in the light we can detect with our eyes, we would only see a small
fraction of what was going on. In other words, it would be like trying to figure out the
action and score of a baseball game while only seeing down the third base line. By
studying all types of light, we can hope to get the full picture of the Universe.
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
ASTRONOMY’S VERSION OF MOORE’S LAW
If these other kinds of telescopes are important, why haven’t
more people heard about them? First, so-called visible light is the
best place to start because humans already have a pair of such
“telescopes”: their eyes. Galileo built on this fact with his
telescope in 1609 and work in “optical” astronomy has
progressed from there.
Other wavelengths, however, had more difficult starts. For
example, X-rays from space are almost entirely absorbed by the
Earth’s atmosphere. This meant that X-ray astronomy could not
begin until humans figured out how to launch satellites and
rockets into space in the middle of the 20 th century. But X-ray
astronomy has grown up quickly and made incredible progress in
just a handful of decades.
Think of Moore’s Law — the one that says computing power will
double every 18 months. X-ray astronomy has been faster than
Moore's law, improving 100 million times in sensitivity in just 36
years.
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
DO X-RAY ASTRONOMERS WEAR LEAD APRONS?
When objects get very hot (or, by
extension, very energetic), they
give off X-rays. Some of the most
intriguing objects in the Universe-
black holes, exploded stars,
clusters of galaxies-reveal much
about themselves through X-rays.
An X-ray machine can't act like
Chandra and photograph an X-ray
source. Chandra, however, can act
like the camera in an X-ray
machine and reveal information
about what's between the source
and the camera.
Med. X-rays
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
FALSE, OR RATHER, REPRESENTATIVE, COLOR
X-rays can’t be seen with the human eye, and don’t have any "color." Images taken by telescopes
that observe at the "invisible" wavelengths are sometimes called false color images. That’s because
the colors used to make them are not real but are chosen to bring out important details. The color
choice is typically used as a type of code in which the colors can be associated with the intensity or
brightness of the radiation from different regions of the image, or with the energy of the emission.
False Color
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
MIRROR, MIRROR ON THE WALL
Another reason why a telescope like the Chandra X-ray Observatory is so remarkably successful is that X-ray
astronomy is very technically challenging. One of the biggest problems is that X-rays that strike a ‘regular’ mirror head
on will just be absorbed. In order to focus X-rays onto a detector, the mirrors have to be shaped like barrels so that the
X-rays strike them at grazing angles, just like pebbles skipping across a pond.
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
http://chandra.harvard.edu/resources/animations/mirror_comparison_lg.mpg
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
FAR OUT ORBIT
The Chandra X-ray Observatory captures X-ray images and measures spectra of many high-energy cosmic
phenomena. Unlike Hubble, its sister “Great Observatory,” Chandra has a highly elliptical orbit that takes it 1/3 of the
way to the Moon. This orbit allows Chandra to observe continuously for many hours at a time, but makes it
unreachable by the Space Shuttle, which was used to launch it back in 1999 . (High Def version available by request)
Orbit
High Res QT: http://chandra.harvard.edu/resources/animations/Dana_BShot_lg_web.mov
QuickTime™ and aYUV420 codec decompressor
are needed to see this picture.
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
8 Years
EIGHT YEARS OF CHANDRA
Highlights of discoveries made with Chandra range from the mysteries surrounding black holes, to the secret lives of galaxies, to the puzzles of dark matter and dark energy. In short, nearly all areas of astrophysics are part of the X-ray Universe.
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
3C321 -A radio galaxy 1.2 billion light years from Earth.
3C321 is a so-called radio galaxy because it belongs to a class of galaxies known to have strong radio emission. Many radio galaxies have powerful jets blasting out of their cores. When astronomers looked at this object, however, they saw something very unusual. They found that the jet from 3C321 appears to be striking another galaxy only about 21,000 light years away. At this distance, less than that between the Earth and the center of the Milky Way, the galaxy being blasted could be experiencing significant disruptions.
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
3C321: MULTIWAVELENGTH, WORKING TOGETHER
This "death star galaxy" was discovered through the combined efforts of both space and ground-based telescopes. NASA's Chandra, Hubble Space Telescope, and Spitzer Space Telescope, plus the Very Large Array (VLA) and MERLIN radio telescopes were required for this result.
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
3C321
QuickTime™ and aSorenson Video 3 decompressorare needed to see this picture.
Scale: Image is 27 arcsec across
Coordinates: RA 15h 31m 42.70s | DEC +24º 04' 25.00”
Observation Date (Chandra): April 30, 2002
Observation Time (Chandra): 13 hours
Credit: X-ray: NASA/CXC/SAO/D.Evans et al.; Optical/UV: NASA/STScI;Radio: NSF/NRAO/VLA
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
IN CONTEXT (X-ray & Radio Full Field)
Jet
Jet
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DEATH STAR ILLUSTRATION
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ANIMATION
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
REQUEST CHANDRA RESOURCES
Resources
http://chandra.harvard.edu/edu/request.html
CHANDRA X-RAY OBSERVATORYHTTP://CHANDRA.HARVARD.EDU
MORE INFORMATION AT CHANDRA
URLs
3C321 (Embargoed until 12/17): http://chandra.harvard.edu/photo/2007/3c321
Related Images: http://chandra.harvard.edu/photo/
Animations & Video:http://chandra.harvard.edu/resources/animations/
Resources:http://chandra.harvard.edu/edu/update.htmlhttp://chandra.harvard.edu/edu/anim.html