Officially known as 1E 0657-56, the Bullet Cluster was formed after the violent collision of two large clusters of galaxies. Located about 3.8 billion light years from Earth, this image combines an image from NASA's Chandra X-ray Observatory with optical data from the Hubble Space Telescope and Magellan telescope in Chile. The cluster has become an extremely popular object for astrophysical research, including studies of the properties of dark matter and the dynamics of million-degree gas.
In this latest research effort, the Bullet Cluster was used to search for the presence of antimatter leftover from the very early universe. Antimatter is made up of elementary particles that have the same masses as their corresponding matter counterparts -- protons, neutrons and electrons -- but the opposite charges and magnetic properties.
Perfect 10
Just a few days after the orbiting observatory was brought back online, Hubble aimed its prime working camera, the Wide Field Planetary Camera 2 (WFPC2), at a particularly intriguing target, a pair of gravitationally interacting galaxies called Arp 147.
This image scores a "perfect 10" both for performance and beauty, demonstrating that the camera works exactly as it did before going offline.
The two galaxies are oriented so that they appear to mark the number 10. The left-most galaxy, or the "one" in this image, is relatively undisturbed apart from a smooth ring of starlight. It appears nearly on edge to our line of sight. The right-most galaxy, resembling a zero, exhibits a clumpy, blue ring of intense star formation.
The blue ring was most probably formed after the galaxy on the left passed through the galaxy on the right. Just as a pebble thrown into a pond creates an outwardly moving circular wave, a propagating density wave was generated at the point of impact and spread outward. As this density wave collided with material in the target galaxy that was moving inward due to the gravitational pull of the two galaxies, shocks and dense gas were produced, stimulating star formation.
The galaxy pair was photographed on October 27-28, 2008. Arp 147 lies in the constellation Cetus, more than 400 million light-years from Earth.
Galaxy Centaurus A
Astronomers have obtained an unprecedented look at the nearest example of galactic cannibalism — a massive black hole hidden at the center of a nearby giant galaxy that is feeding on a smaller galaxy in a spectacular collision. Such fireworks were common in the early universe, as galaxies formed and evolved, but are rare today.
The Hubble telescope offers a stunning unprecedented close-up view of a turbulent firestorm of star birth along a nearly edge-on dust disk girdling Centaurus A, the nearest active galaxy to Earth. The picture at upper left shows the entire galaxy. The blue outline represents Hubble's field of view. The larger, central picture is Hubble's close-up view of the galaxy. Brilliant clusters of young blue stars lie along the edge of the dark dust lane. Outside the rift the sky is filled with the soft hazy glow of the galaxy's much older resident population of red giant and red dwarf stars.
Saturn
As Saturn grows closer through the eyes of the Cassini spacecraft, which is hurtling toward a rendezvous with the ringed world on June 30 2004, both Cassini and the Earth-orbiting Hubble Space Telescope snapped spectacular pictures of the planet and its magnificent rings. Cassini is approaching Saturn at an oblique angle to the Sun and from below the ecliptic plane. Cassini has a very different view of Saturn than Hubble's Earth-centered view. For the first time, astronomers can compare views of equal-sharpness of Saturn from two very different perspectives.
Carina Nebula
When 19th century astronomer Sir John Herschel spied a swirling cloud of gas with a hole punched through it, he dubbed it the Keyhole Nebula. Now the Hubble telescope has taken a peek at this region, and the resulting image reveals previously unseen details of the Keyhole's mysterious, complex structure. The Keyhole is part of a larger region called the Carina Nebula (NGC 3372), about 8,000 light-years from Earth.
Note: You might recognize the logo at the top of my blog as the Carina Nebula.
That's all!
--->Susan
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