Colliding Galaxies

Hubble captures two galaxies colliding.  Image: Credit: NASA and ESA Acknowledgment: A. Gal-Yam (Weizmann Institute of Science)

Hubble captures two galaxies colliding. Image: Credit: NASA and ESA Acknowledgment: A. Gal-Yam (Weizmann Institute of Science)

This is an amazing image. Hubblesite has a “zoomable” version of this and I’ve been trying to count the smaller more distant galaxies – I’m at 22 other than the two subjects of the image.

This NASA Hubble Space Telescope photo of NGC 7714 presents an especially striking view of the galaxy’s smoke-ring-like structure. The golden loop is made of sun-like stars that have been pulled deep into space, far from the galaxy’s center. The galaxy is located approximately 100 million light-years from Earth in the direction of the constellation Pisces.
The universe is full of such galaxies that are gravitationally stretched and pulled and otherwise distorted in gravitational tug-o’-wars with bypassing galaxies.

The companion galaxy doing the “taffy pulling” in this case, NGC 7715, lies just out of the field of view in this image. A very faint bridge of stars extends to the unseen companion. The close encounter has compressed interstellar gas to trigger bursts of star formation seen in bright blue arcs extending around NGC 7714’s center.

The gravitational disruption of NGC 7714 began between 100 million and 200 million years ago, at the epoch when dinosaurs ruled the Earth.

The image was taken with the Wide Field Camera 3 and the Advanced Camera for Surveys in October 2011.
The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington, D.C.

Comet Dust

Dust particles from Comet 67P/Churyumov-Gerasimenko collected by ESA's Rosetta spacecraft. Copyright ESA/Rosetta/MPS for COSIMA Team MPS/CSNSM/UNIBW/TUORLA/IWF/IAS/ESA/ BUW/MPE/LPC2E/LCM/FMI/UTU/LISA/UOFC/vH&S

Dust particles from Comet 67P/Churyumov-Gerasimenko collected by ESA’s Rosetta spacecraft. Copyright ESA/Rosetta/MPS for COSIMA Team MPS/CSNSM/UNIBW/TUORLA/IWF/IAS/ESA/ BUW/MPE/LPC2E/LCM/FMI/UTU/LISA/UOFC/vH&S

One of the instruments on board ESA’s Rosetta called COSIMA, short for the COmetary Secondary Ion Mass Analyser one of three dust analysis experiments.

Essentially this instrument has a plate for catching dust grains from the comet at fairly low speeds. The dust grains shown above is two of the grains collected and they have yielded some interesting results.

I’ll let ESA explain:

Two examples of dust grains collected by Rosetta’s COmetary Secondary Ion Mass Analyser (COSIMA) instrument in the period 25–31 October 2014. Both grains were collected at a distance of 10–20 km from the comet nucleus. Image (a) shows a dust particle (named by the COSIMA team as Eloi) that crumbled into a rubble pile when collected; (b) shows a dust particle that shattered (named Arvid).

For both grains, the image is shown twice under two different grazing illumination conditions: the top image is illuminated from the right, the bottom image from the left. The brightness is adjusted to emphasise the shadows, in order to determine the height of the dust grain. Eloi therefore reaches about 0.1 mm above the target plate; Arvid about 0.06 mm. The two small grains at the far right of image (b) are not part of the shattered cluster.

The fact that the grains broke apart so easily means their individual parts are not well glued together. If they contained ice they would not shatter; instead, the icy component would evaporate off the grain shortly after touching the collecting plate, leaving voids in what remained. By comparison, if a pure water-ice grain had struck the detector, then only a dark patch would have been seen.

These ‘fluffy’ grains are thought to originate from the dusty layer built up on the comet’s surface since its last close approach to the Sun, and will soon be lost into the coma.

Be sure to check the Rosetta Blog. The have this and results from six other Rosetta’s science instruments since arriving at Comet 67P/Churyumov-Gerasimenko – great stuff!!

Latest Ceres Approach Image

The latest Dawn image of Ceres.  Image: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The latest Dawn image of Ceres. Image: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

The dwarf planet Ceres is coming into focus little by little as the Dawn spacecraft approaches. The image above is around 30 percent increase in resolution over Hubble images and we are just beginning to make out details. The light colored spot on the upper part of the planet is looking like a mountain to my untrained eye or it could as easily be a deep and newly formed crater.

Dawn will arrive at Ceres in just a couple of weeks and enter orbit on 06 March.

If some of you are wondering why Ceres being called a dwarf planet instead of an asteroid as a lot of us were taught. The new classification came with the new definition of a planet in 2006.

Here’s the caption from NASA:

This image, taken 147,000 miles (237,000 kilometers) from Ceres on January 25, 2015 by NASA’s Dawn spacecraft, is part of a series of views representing the best look so far at the dwarf planet. The image is 43 pixels across, representing a higher resolution than images of Ceres taken by the Hubble Space Telescope in 2003 and 2004.
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Asteroid With a Moon

Asteroid 2004 BL86 made a relatively close pass yesterday. The asteroid passed about 3.1 lunar distances from Earth or 1.2 million km / 745,000 miles. In cosmic scales that is indeed close. The asteroid is 325 meters / 1,100 feet in diameter, not something we would want to hit us!

Scientists used the Deep Space Network antenna at Goldstone California took took radar images of the asteroid and assembled 20 of them into this video and look at what they found – the asteroid has a moon! Actually about 16 percent of the near-Earth population of asteroids of 200 meters in diameter (655 feet) have moons and a few have two. This particular moon is 70 meters (230 feet) across.

The observations of the asteroid enabled scientists to get data on the orbit to predict future close passes and this asteroid will not make another pass this close for 200 years. We do have others though, the next known asteroid to make a close pass is called 1999 AN10 in 2027.

The asteroid was found on Jan. 30, 2004, by the Lincoln Near-Earth Asteroid Research (LINEAR) survey in White Sands, New Mexico, one of a handful of observing groups around the world looking for these very difficult to find objects.

Video source

Miranda

The inner most large moon of Uranus.  Credit: NASA/JPL

The inner most large moon of Uranus. Credit: NASA/JPL

Miranda is probably one of the more bizarre moons in our solar system as we can see in this Voyager image. This inner moon of Uranus is about half rock and water ice. Accounting for the tortured terrain has been a challenge originally it was thought Miranda was shattered and reassembled, however more recently that scenario has been replaced by upwelling of partially melted ices from the interior.

Check out our Miranda page for more about the moon including vital statistics.

Here is the original NASA/JPL caption for the image:

Miranda, innermost of Uranus’ large satellites, is seen at close range in this Voyager 2 image, taken Jan. 24, 1986, as part of a high-resolution mosaicing sequence. Voyager was some 36,000 kilometers (22,000 miles) away from Miranda. This clear-filter, narrow-angle image shows an area about 250 km (150 mi) across, at a resolution of about 800 meters (2,600 feet). Two distinct terrain types are visible: a rugged, higher-elevation terrain (right) and a lower, striated terrain. Numerous craters on the rugged, higher terrain indicate that it is older than the lower terrain. Several scarps, probably faults, cut the different terrains. The impact crater in the lower part of this image is about 25 km (15 mi) across. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.

Huge SDO Milestone

100 millionth image from SDO. Credit: SDO

100 millionth image from SDO. Credit: SDO

Almost hard to imagine, one hundred million images from the Solar Dynamics Laboratory!

Congraduations to the AIA team!

Yesterday, January 19, 2015, at 1749 UTC (12:49 pm ET) the AIA instrument recorded its 100,000,000th image. Here it is, an AIA 193 Å image showing coronal holes in both the northern and southern hemispheres. More information, including some favorite images from team members, is available at the NASA SDO webpage.
The AIA team at LMSAL worked hard to design and build the AIA telescopes, even overcoming a delayed start way back at the beginning of the SDO project. The team continues to operate the instrument, keeping it calibrated and listing the features seen on the Sun. The HMI JSOC team at Stanford University maintains the archive that serves the images to our large and growing number of users.

Cometary Wisps

Rosetta images the dust coming off Comet 67P/Churyumov-Gerasimenko  Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

Rosetta images the dust coming off Comet 67P/Churyumov-Gerasimenko Credits: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA

ESA’s Rosetta spacecraft took this image of Comet 67P/Churyumov-Gerasimenko last November with the OSIRIS camera. By overexposing the comet the wisps of cometary dust is highlighted.

Rosetta has an instrument called MIDAS and its job is to capture 67P/C-G particles. About the time this image was taken MIDAS captured a particle measuring 10 micrometres, which is way larger than was expected.

From the Rosetta blog (be sure to check it out)

“This is still the beginning of the activity compared to what we expect to see in summer this year,” says OSIRIS principal investigator Holger Sierks from the Max Planck Institute for Solar System Research (MPS) in Germany. “From the last perihelion passage we know that the comet will evolve by a factor of 100 in activity at that time compared to now.”