Great Space Imagery

December 13, 2007

Cassini-Huygens

Four NASA spacecraft have been sent to explore Saturn. Pioneer 11 was first to fly past Saturn in 1979. Voyager 1 flew past a year later, followed by its twin, Voyager 2, in 1981.

The Cassini spacecraft is the first to explore the Saturn system of rings and moons from orbit. Cassini entered orbit on Jun. 30, 2004 and immediately began sending back intriguing images and data. The European Space Agency’s Huygens Probe dove into Titan’s thick atmosphere in January 2005. The sophisticated instruments on both spacecraft are providing scientists with vital data and the best views ever of this mysterious, vast region of our solar system. (source: http://saturn.jpl.nasa.gov/overview/index.cfm)

This image, from Cassini, shows a great overview of Saturn occulting the Sun. This unique view allows us to see the newly discovered E ring.

 

CGRO Science Support Center

The Compton Gamma Ray Observatory was the second of NASA’s Great Observatories. Compton, at 17 tons, was the heaviest astrophysical payload ever flown at the time of its launch on April 5, 1991 aboard the space shuttle Atlantis. Compton was safely deorbited and re-entered the Earth’s atmosphere on June 4, 2000.

Compton had four instruments that covered an unprecedented six decades of the electromagnetic spectrum, from 30 keV to 30 GeV. In order of increasing spectral energy coverage, these instruments were the Burst And Transient Source Experiment (BATSE), the Oriented Scintillation Spectrometer Experiment (OSSE), the Imaging Compton Telescope (COMPTEL), and the Energetic Gamma Ray Experiment Telescope (EGRET). For each of the instruments, an improvement in sensitivity of better than a factor of ten was realized over previous missions.

The Observatory was named in honor of Dr. Arthur Holly Compton, who won the Nobel prize in physics for work on scattering of high-energy photons by electrons - a process which is central to the gamma-ray detection techniques of all four instruments. (Souce: http://cossc.gsfc.nasa.gov/docs/cgro/index.html)

This image from CGRO was taken using Gamma ray imaging of the entire celestial sphere. The band across the middle is the Milky Way Galaxy.

 

XMM-Newton

Many celestial objects generate X-rays in extremely violent processes. But Earth’s atmosphere blocks out these X-rays, messengers of what occurred in the distant past when stars were born or died, and clues to our future. Only by placing X-ray detectors in space can such sources be detected, pinpointed and studied in detail. XMM-Newton, the largest science satellite ever built in Europe, has an unprecedented sensitivity.

XMM-Newton carries three very advanced X-ray telescopes. They each contain 58 high-precision concentric mirrors, delicately nested to offer the largest collecting area possible to catch the elusive X-rays. These Mirror Modules allow XMM-Newton to detect millions of sources, far more than any previous X-ray mission. (Source: http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=31249)

This image from XMM-Newton is a composite X-ray and optical image of the Eskimo Nebula (NGC 2392).

 

Spitzer Space Telescope

The Spitzer Space Telescope (formerly SIRTF, the Space Infrared Telescope Facility) was launched into space by a Delta rocket from Cape Canaveral, Florida on 25 August 2003. During its mission, Spitzer will obtain images and spectra by detecting the infrared energy, or heat, radiated by objects in space between wavelengths of 3 and 180 microns (1 micron is one-millionth of a meter). Most of this infrared radiation is blocked by the Earth’s atmosphere and cannot be observed from the ground. (Source: http://www.spitzer.caltech.edu/about/index.shtml)

This image from Spitzer shows us a great view of the Helix Nebula (NGC 7293).

 

New Horizons

Planetary exploration is a historic endeavor and a major focus of NASA. New Horizons is designed to help us understand worlds at the edge of our solar system by making the first reconnaissance of Pluto and Charon - a “double planet” and the last planet in our solar system to be visited by spacecraft. Then, as part of an extended mission, New Horizons would visit one or more objects in the Kuiper Belt region beyond Neptune. (Source: http://pluto.jhuapl.edu/overview/whyGo.php)

This photo shows Io eclipsing Jupiter as New Horizons makes its way to Pluto.

Galaxy Evolution Explorer

The Galaxy Evolution Explorer (GALEX) is an orbiting space telescope that will observe galaxies in ultraviolet light across 10 billion years of cosmic history. Such observations will tell scientists how galaxies, the basic structures of our Universe, evolve and change. Additionally, GALEX will probe the causes of star formation during a period when most of the stars and elements we see today had their origins. (Source: http://www.galex.caltech.edu/ABOUT/about.html)

Here we see the galaxy Messier 31 from Andromeda, this is actually a mosaic of 10 different images from GALEX.

Hubble Space Telescope

Named after the trailblazing astronomer Edwin P. Hubble (1889-1953), the Hubble Space Telescope (HST) is a large, space-based observatory which has revolutionized astronomy by providing unprecedented deep and clear views of the Universe, ranging from our own solar system to extremely remote fledgling galaxies forming not long after the Big Bang 13.7 billion years ago.

Launched in 1990 and greatly extended in its scientific powers through new instrumentation installed during four servicing missions with the Space Shuttle, the Hubble, in its sixteen years of operations, has validated Lyman Spitzer Jr.’s (1914-1997) original concept of a diversely instrumented observatory orbiting far above the distorting effects of the Earth’s atmosphere and returning data of unique scientific value.

Hubble’s coverage of light of different colors (its “spectral range”) extends from the ultraviolet, through the visible (to which our eyes are sensitive), and into the near-infrared. Hubble’s primary mirror is 2.4 meters (94.5 inches) in diameter. Hubble is not large by ground-based standards but it achieves heroically in space. Hubble orbits Earth every 97 minutes, 575 kilometers (360 miles) above the Earth’s surface. (source: http://hubble.nasa.gov/)

This historic new view is actually two separate images taken by Hubble’s Advanced Camera for Surveys (ACS) and the Near Infrared Camera and Multi-object Spectrometer (NICMOS). Both images reveal galaxies that are too faint to be seen by ground-based telescopes, or even in Hubble’s previous faraway looks, called the Hubble Deep Fields (HDFs), taken in 1995 and 1998. (source: http://hubblesite.org/newscenter/archive/releases/2004/07/text/)

Swift Gamma-Ray Burst Mission

Gamma-ray bursts (GRBs) are the most powerful explosions the Universe has seen since the Big Bang. They occur approximately once per day and are brief, but intense, flashes of gamma radiation. They come from all different directions of the sky and last from a few milliseconds to a few hundred seconds. So far scientists do not know what causes them. Do they signal the birth of a black hole in a massive stellar explosion? Are they the product of the collision of two neutron stars? Or is it some other exotic phenomenon that causes these bursts?

With Swift, a NASA mission with international participation, scientists will now have a tool dedicated to answering these questions and solving the gamma-ray burst mystery. Its three instruments will give scientists the ability to scrutinize gamma-ray bursts like never before. Within seconds of detecting a burst, Swift will relay a burst’s location to ground stations, allowing both ground-based and space-based telescopes around the world the opportunity to observe the burst’s afterglow. Swift is part of NASA’s medium explorer (MIDEX) program and was launched into a low-Earth orbit on a Delta 7320 rocket on November 20, 2004. (source: http://swift.gsfc.nasa.gov/docs/swift/swiftsc.html)

This image shows a before and after of Supernova 2006X.

STEREO (Solar TErrestrial RElations Observatory)

STEREO (Solar TErrestrial RElations Observatory) is the third mission in NASA’s Solar Terrestrial Probes program (STP). This two-year mission will employ two nearly identical space-based observatories - one ahead of Earth in its orbit, the other trailing behind - to provide the first-ever stereoscopic measurements to study the Sun and the nature of its coronal mass ejections, or CMEs.

STEREO’s scientific objectives are to:

• Understand the causes and mechanisms of coronal mass ejection (CME) initiation.
• Characterize the propagation of CMEs through the heliosphere.
• Discover the mechanisms and sites of energetic particle acceleration in the low corona and the interplanetary medium.
• Improve the determination of the structure of the ambient solar wind.

(source: http://stereo.gsfc.nasa.gov/mission/mission.shtml)

This is an image of Sol (our Sun) from STEREO.

Chandra X-Ray Observatory

NASA’s Chandra X-ray Observatory, which was launched and deployed by Space Shuttle Columbia on July 23, 1999, is the most sophisticated X-ray observatory built to date.

Chandra is designed to observe X-rays from high-energy regions of the universe, such as the remnants of exploded stars. The two images of the Crab Nebula supernova remnant and its pulsar shown below illustrate how higher resolution can reveal important new features. (source: http://chandra.harvard.edu/about/axaf_mission.html)

This image shows the remenants of the Tycho Supernova.

Bonus: Hubble/Spitzer

This image is a composite of an image from the HST and the Spitzer Space Telescope (see above), it shows the Orion Nebula

Posted in Astronomy