| Piú viste - Asteroids and Comets |
Dart-4.jpgGreat Balls of Fire! - 463 visitenessun commentoMareKromium
|
|
EROS-PIA03129.jpgEros from above (2)62 visiteNEAR Shoemaker photographed this area of Eros on December 18, 2000, from an orbital altitude of 33 Km. This part of the asteroid's surface, like many others, appears vaguely "sculptured" due to its low, elongated ridges and depressions with seemingly consistent orientations. Some of the low spots also contain accumulations of smooth, pond-like materials. Neither the surface sculpturing nor the pond-like materials are well understood, and both will be investigated in detail using even higher-resolution images from NEAR Shoemaker's low passes over Eros in early 2001. The whole scene is about 1 Km across.
|
|
Asteroids-Annefrank_Asteroid-PIA02885_modest.jpgAsteroid Annefrank from Stardust62 visiteAsteroid Annefrank is seen as irregularly shaped, cratered body in an image taken by NASA's Stardust spacecraft during a Nov. 2 flyby of the asteroid.
Stardust flew within about 3.300 Km (about 2.050 miles) of the asteroid as a rehearsal for the spacecraft's encounter with its primary target, comet Wild 2, in January 2004. The camera's resolution was sufficient to show that Annefrank is about 8 Km (5 miles) in length, twice the predicted size from Earth-based observations. The surface reflects about 0,1 to 0,2% of sunlight, slightly less than anticipated. A few craters that are hundreds of meters across can be seen. The straight edge in the right side of the image may be an artifact of processing.
|
|
Asteroids_from_HST-00.jpgAsteroids, from HST (1)61 visiteCaption NASA originale da "NASA - Picture of the Day" del 18 Aprile 2005:"Rocks from space hit Earth every day. The larger the rock, though, the less often Earth is struck. Many kilograms of space dust pitter to Earth daily. Larger bits appear initially as a bright meteor. Baseball-sized rocks and ice-balls streak through our atmosphere daily, most evaporating quickly to nothing. Significant threats do exist for rocks near 100 meters in diameter, which strike the Earth roughly every 1000 years. An object this size could cause significant tsunamis were it to strike an ocean, potentially devastating even distant shores. A collision with a Massive asteroid, over 1 Km across, is more rare, occurring typically millions of years apart, but could have truly global consequences".
|
|
Comets-Comet_Holmes-UZ.jpgComet 17-P-Holmes, from Italy61 visiteRecent development from 17-P-Holmes: this picture is a deep image from L'Aquila, Italy on November 8, 2007.
It shows the ion tail disconnecting from the comet (just like it happened to the Encke Comet).
MareKromium
|
|
Lutetia-02.jpgAsteroid "Lutetia"61 visiteThough the first look of the giant asteroid, through nearly 400 images, has revealed a lot about the primitive survivor's cratered surface, a lot more needs to be unlocked.
The data collected by Rosetta Spacecraft, with the help of multi-wavelength cameras, spectrometers etc., will unravel the mysteries surrounding the composition of Lutetia. Some asteroids are a broken part of iron-rich cores of proto-planets or they may just be composed of Carbon.MareKromium
|
|
Eros from 250 mt - PIA03147_modest.jpgFalling down: Eros from 250 mt60 visiteCaption NASA:"...The image is 12 meters across. The cluster of rocks at the upper right measures 1.4 meters across...". Vale quanto gi detto in precedenza: riuscite a vedere dei dettagli gi presenti nel frame precedente?!?
NEAR, scendendo, fotografa "random"?
|
|
Comets-Hale-Bopp-00.jpgHale-Bopp - HST (1)60 visiteDue immagini della famosissima Cometa Hale Bopp che, qualche anno fa, ci tenne tutti con il naso "all'ins" per qualche tempo.
Queste immagini (HST) nascondono un'Anomalia che hanno evidenziato (a quanto ne sappiamo) solo pochi Ricercatori: alla Sn del nucleo di Hale-Bopp - per di chi guarda il secondo dei due frames - si vede qualcosa (una sorta di "nuvoletta") che gli Scienziati si sono ben guardati dal tentare di interpretare (forse per paura di fare figuracce e/o di dire sciocchezze...). Di che cosa si tratta? Un frammento della Cometa? Un difetto dell'immagine? O forse, come dicono i Ricercatori pi smaliziati, una "Nave Spaziale" che seguiva la cometa - ed ora perdonateci il gioco di parole - "accodandosi" ad essa?!?...
|
|
Itokawa-05.jpgOrbiting around Itokawa (2)60 visiteHayabusa is a technology demonstration spacecraft focusing on key technologies that are required for future large-scale sample and return missions, yet is also making new scientific observations and discoveries. The technology demonstration component of the mission consists of 5 goals:
1) ion engine propulsion in interplanetary cruise;
2) ion engine propulsion in combination with an Earth gravity assist;
3) autonomous guidance and navigation using optical measurements;
4) collection of surface samples in an ultra-low gravity environment and
5) the direct recovery of these samples on the ground after its return from interplanetary flight.
To date the Hayabusa project has accomplished these demonstrations up through
the third goal.
|
|
Comets-Schwassmann_Wachmann_1-05.jpgComet Schwassmann-Wachmann 3, M 57 and IC 129660 visiteAs dawn approached on May 8, 2006, astronomer Stefan Seip carefully watched Fragment "C" of broken Comet 73P/Schwassmann-Wachmann 3 approach M 57 - the Ring Nebula, and faint spiral galaxy IC 1296.
Of course, even though the trio seemed to come close together in a truly cosmic photo opportunity, the comet is in the inner part of our Solar System, a mere 0,5 Light-Minutes (LM) or so from Seip's telescope located near Stuttgart, Germany, planet Earth.
The Ring Nebula (upper right) is more like 2000 LY distant, well within our own Milky Way Galaxy. At a distance of 200 MLY, IC 1296 (between the Comet and the Ring Nebula) is beyond even the Milky Way's boundaries. Because the Comet is so close, it appears to move relatively rapidly against the distant stars. This dramatic telescopic view was composited from two sets of images; one compensating for the Comet's apparent motion and one recording the background stars and nebulae.
|
|
McNaught-09.jpgThe "Tail" of McNaught, at Sunset...60 visiteCaption NASA originale:"What's happening over the horizon? Many a sky enthusiast who thought they had seen it all had never seen anything like this. To the surprise of many Northern Hemisphere observers, the tail of Comet McNaught remained visible even after the comet's head set ahead of the Sun. What's more, visible were bright but extremely rare filamentary striae from the comet's expansive dust tail. The cause of dust tail striae are not known for sure, but are possibly related to fragmentation of comet's nucleus. The last comet to show prominent striae was Comet Hale-Bopp in 1997.
Pictured above, the tail of Comet McNaught was caught just after Sunset last Friday above the Carnic Alps of Northern Italy".
|
|
LLO-ST_2539423137_v.jpgThe unbelievable surface of 25143-Itokawa (HR4 - possible natural colors; elab. Lunexit)60 visitenessun commentoMareKromium
|
|
| 271 immagini su 23 pagina(e) |
 |
|
|
|
|
8 | |
|
|
|
|
