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OPP-SOL1512-3.jpgVictoria's Paving - Sol 1512 (True Colors; credits: Dr G. Barca)60 visitenessun commentoMareKromium
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NGC-0253-HST.jpgCosmic Alignment! (2MASX J00482185-2507365)60 visiteNASA's Hubble Space Telescope has captured a rare alignment between two spiral galaxies. The outer rim of a small, foreground galaxy is silhouetted in front of a larger background galaxy. Skeletal tentacles of dust can be seen extending beyond the small galaxy's disk of starlight.
Such outer dark dusty structures, which appear to be devoid of stars, like barren branches, are rarely so visible in a galaxy because there is usually nothing behind them to illuminate them. Astronomers have never seen dust this far beyond the visible edge of a galaxy. They do not know if these dusty structures are common features in galaxies.
Understanding a galaxy's color and how dust affects and dims that color are crucial to measuring a galaxy's true brightness. By knowing the true brightness, astronomers can calculate the galaxy's distance from Earth.
Astronomers calculated that the background galaxy is 780 MLY away. They have not as yet calculated the distance between the two galaxies, although they think the two are relatively close, but not close enough to interact. The background galaxy is about the size of the Milky Way Galaxy and is about 10 times larger than the foreground galaxy.
Most of the stars speckled across this image belong to the nearby spiral galaxy NGC 253, which is out of view to the right. Astronomers used Hubble's Advanced Camera for Surveys to snap images of NGC 253 when they spied the two galaxies in the background. From ground-based telescopes, the two galaxies look like a single blob. But the Advanced Camera's sharp "eye" distinguished the blob as two galaxies, cataloged as 2MASX J00482185-2507365. The images were taken on Sept. 19, 2006.
The results have been submitted for publication in The Astronomical Journal.
For additional information, contact:
Donna Weaver/Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4493 / 410-338-4514
dweaver@stsci.edu / villard@stsci.edu
Benne Holwerda
Space Telescope Science Institute, Baltimore, Md.
/University of Cape Town, South Africa
holwerda@stsci.edu
Object Name: 2MASX J00482185-2507365
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Panoramic-AS17-137-20997-21004.jpgFrom AS 17-137-20997 until 21004 (EVA-2; Shorty Crater)60 visitenessun commentoMareKromium
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OPP-SOL1521-1.jpgVictoria's Paving - Sol 1521 (True Colors; credits: Dr G. Barca)60 visitenessun commentoMareKromium
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Panoramic-AS12-47-6946-6949.jpgFrom AS 12-47-6946 until 6949 (EVA-1; Surveyor Crater)60 visitenessun commentoMareKromium
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Panoramic-AS11-40-5888-5891.jpgFrom AS 11-40-5888 until 5891 (Processed in natural colors - Unnamed double-crater)60 visitenessun commentoMareKromium
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SOU-SOL018-PresidentialPanorama-01.jpgPresidential Panorama - Full Daylight -, Part II - Sol 18 (possible True Colors; credits: Dr G. Barca & Lunexit)60 visitenessun commentoMareKromium
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SOU-SOL026-Mini_Matsuperres-2.jpgDeflated Air-Bags and Disturbed Terrain - Sol 26 (natural colors; credits: Dr G. Barca)60 visitenessun commentoMareKromium
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SOU-SOL080-LXT.jpgAres' Horizon and a "tired" Soujourner ... - Sol 80 (natural colors; credits: Lunexit)60 visitenessun commentoMareKromium
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Psp_009548_1420_red.jpgEnigmatic Terrain in Hellas Planitia (Saturated Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)60 visiteHellas Planitia is the low-lying plain on the floor of the Hellas Basin, an ancient impact crater over 2000 Km wide. This Basin includes the lowest point on the surface of Mars.
A variety of unusual landforms occur on the floor of the basin due to the low elevation. One hypothesis is that Hellas may once have held lakes or seas, possibly with thick ice that might account for some of these features.
This image shows a small portion of Western Hellas, in a Region of "Enigmatic Ridges".
These ridges form an intricate pattern, enclosing kilometer-wide depressions. These strange features are still not well-understood; one possibility is that they formed in lake-bottom sediments when ice covering the lake touched bottom and shoved wet, loose material to the side.
This HiRISE image reveals that the ridges contain many boulders; sediments deposited on the bottom of a lake might be fine-grained, although they may have hardened to rock later. The image also shows lineations, probably outcropping layers, running between the large ridges.
Because the resolution of HiRISE images is sufficient to see details such as the abundance of boulders and the presence of thin sedimentary layers, images of this and other poorly-understood terrains will be important in interpreting the geological and climatological history of Mars.
This observation is part of a stereo pair along with PSP_007834_1420.MareKromium
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NGC-3324-HST.jpgNGC 3324 - Star-forming Region60 visiteThe landmark 10th anniversary of the Hubble Space Telescope's Hubble Heritage Project is being celebrated with a 'landscape' image from the cosmos. Cutting across a nearby star-forming region are the "hills and valleys" of gas and dust displayed in intricate detail. Set amid a backdrop of soft, glowing blue light are wispy tendrils of gas as well as dark trunks of dust that are light-years in height.
The Hubble Heritage Project, which began in October 1998, has released nearly 130 images mined from the Hubble data archive as well as a number of observations taken specifically for the project. By releasing a new, previously unseen Hubble image every month, the team's intent was to showcase some of the most attractive images ever taken by the Hubble telescope, and share them with a wide audience. The Heritage team continues to create aesthetic images that present the universe from an artistic perspective.
This month's three-dimensional-looking Hubble image shows the edge of the giant gaseous cavity within the star-forming region called NGC 3324. The glowing nebula has been carved out by intense ultraviolet radiation and stellar winds from several hot, young stars. A cluster of extremely massive stars, located well outside this image in the center of the nebula, is responsible for the ionization of the nebula and excavation of the cavity.
The image also reveals dramatic dark towers of cool gas and dust that rise above the glowing wall of gas. The dense gas at the top resists the blistering ultraviolet radiation from the central stars, and creates a tower that points in the direction of the energy flow. The high-energy radiation blazing out from the hot, young stars in NGC 3324 is sculpting the wall of the nebula by slowly eroding it away.
Located in the Southern Hemisphere, NGC 3324 is at the northwest corner of the Carina Nebula (NGC 3372), home of the Keyhole Nebula and the active, outbursting star Eta Carinae. The entire Carina Nebula complex is located at a distance of roughly 7,200 light-years, and lies in the constellation Carina.
This image is a composite of data taken with two of Hubble's science instruments. Data taken with the Advanced Camera for Surveys (ACS) in 2006 isolated light emitted by hydrogen. More recent data, taken in 2008 with the Wide Field Planetary Camera 2 (WFPC2), isolated light emitted by sulfur and oxygen gas. To create a color composite, the data from the sulfur filter are represented by red, from the oxygen filter by blue, and from the hydrogen filter by green.
The Heritage project has released images using several of Hubble's optical cameras: the Wide Field Planetary Camera (WF/PC), which was installed when the telescope was first deployed in 1990; WFPC2, which replaced WFPC in 1993 and is still in service today; and ACS, which was added in 2002. After the Hubble Servicing Mission in early 2009, the Hubble Heritage team hopes to continue using ACS as well as the newest of the optical cameras, Wide Field Camera 3.
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Crux.jpgThe Southern Cross (and the Carina Region)60 visite"...Teach me the way I should go, for to you I lift up my soul..."
- Psalm 143:8MareKromium
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