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000-Ceres~0.jpgBig Asteroid or Small Planet?67 visiteLa decisione non è stata ancora presa, ma il problema rimane: 1-Cerere è un "grande" Asteroide o un "piccolo" Pianeta?
A parte tutto, Cerere sembra proprio essere un mondo a sè: le sue dimensioni (circa 930 Km di iametro) sono modeste ma, per un asteroide, alquanto consistenti (Cerere è comunque l'oggetto conosciuto più grande fra le (decine di) migliaia che si trovano in quella regione di spazio compresa fra le orbite di Marte e Giove e che è comunemente conosciuta come "Cintura degli Asteroidi" (o Asteroids' Belt).
Di 1-Cerere si parla molto in questi giorni perchè la IAU (International Astronomical Union) sta valutando se conferire a questo Corpo Celeste lo "status" di Pianeta vero e proprio oppure no, ma la NASA - a quanto si sa - era già da tempo interessata a questo piccolo mondo ed infatti, proprio in questi giorni, è in fase di completamento la preparazione della Sonda "Dawn" (alba) la quale verrà lanciata nel 2007 (forse a Giugno) e che dovrebbe raggiungere e studiare MOLTO da vicino l'asteroide Vesta (nel 2011) e - guarda caso... - proprio 1-Cerere, nel 2015 (l'Anno del possibile - ed auspicabile - "contatto" fra l'altra Sonda New Horizons ed il Doppio Pianeta - o Sistema Binario formato da - Plutone e Caronte.
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001-Ceres-alone.jpg1-Ceres from Hubble Space Telescope61 visiteNASA's Hubble Space Telescope took these images of the asteroid 1 Ceres over a 2-hour and 20-minute span, the time it takes the Texas-sized object to complete one quarter of a rotation. One day on Ceres lasts 9 hours.
Hubble snapped 267 images of Ceres as it watched the asteroid make more than one rotation. By observing the asteroid during a full rotation, astronomers confirmed that Ceres has a nearly round body like Earth's. Ceres' shape suggests that its interior is layered like those of terrestrial planets such as Earth. Ceres may have a rocky inner core, an icy mantle, and a thim, dusty, outer crust.
The "Bright Spot" that we see is a mistery: it is (obviously) brighter than its surroundings, but it is still very dark (very low albedo) reflecting only a small portion of Sunlight.
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004-Ceres.jpgMoments of 1-Ceres (1)54 visiteDa "NASA - Picture of the Day", del 21 Agosto 2006:"Is 1-Ceres an Asteroid or a Planet?
Although a trivial designation to some, the recent suggestion by the Planet Definition Committee of the International Astronomical Union would have 1-Ceres reclassified from Asteroid to Planet.
A change in taxonomy might lead to more notoriety for the frequently overlooked world. Ceres, at about 1000 Km across, is the largest object in the main Asteroid Belt between Mars and Jupiter. Under the newly proposed criteria, Ceres would qualify as a planet because it is nearly spherical and sufficiently distant from other planets. Pictured above is the best picture yet of Ceres, taken by the Hubble Space Telescope as part of a series of exposures ending in 2004 January. Currently, NASA's Dawn mission is scheduled to launch in 2007 June to explore Ceres and Vesta, regardless of their future designations".
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005-Ceres.jpgMoments of 1-Ceres (2)55 visiteFor 2 centuries it was the largest known rock in the Solar System. The Texas-sized asteroid Ceres, about 930 Km (about 580 miles) across, was the first asteroid ever detected. The space rock was identified in 1801 by astronomer Giuseppe Piazzi, a monk in Sicily and the founding director of the Palermo Astronomical Observatory. He noted over a few nights a shifting point in the sky that wasn't one of the planets, their moons or a star. Thus, he discovered the rock.
After discovering the asteroid, Piazzi was invited to join the Celestial Police, a group of 24 international astronomers looking for what they called "guest planets" between Mars and Jupiter. The Celestial Police noted that the spacing between planets was fairly regular, but that there was a large gap between Mars and Jupiter.
Soon other small bodies were discovered in that region (Pallas in 1802, Juno in 1804 and Vesta in 1807), so the Celestial Police concluded that not just one, but many minor planets had to exist in a Main Asteroid Belt.
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006-Ceres.jpg1-Ceres (natural colors, from HST - credits: NASA/ESA et al.)55 visiteThe Hubble image of Ceres on the reveals bright and dark regions on the asteroid's surface that could be topographic features, such as craters, and/or areas containing different surface material. Large impacts may have caused some of these features and potentially added new material to the landscape. The Texas-sized asteroid holds about 30 to 40% of the mass in the Asteroid Belt.
Ceres' round shape suggests that its interior is layered like those of terrestrial planets such as Earth. The asteroid may have a rocky inner core, an icy mantle, and a thin, dusty outer crust. The asteroid may even have water locked beneath its surface. It is approx. 590 miles (950 Km) across and was the first asteroid discovered in 1801.
The observation was made in visible and ultraviolet light between December 2003 and January 2004 with the HST Advanced Camera for Surveys. The color variations in the image show either a difference in texture or composition on Ceres' surface.
Astronomers need the close-up views of the Dawn spacecraft to determine the characteristics of these regional differences.
MareKromium
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007-Ceres-PIA10235.jpg1-Ceres (natural colors, from HST - credits: NASA/ESA et al.)57 visiteCaption NASA:"This is a NASA Hubble Space Telescope color image of 1-Ceres, the largest object in the Asteroid Belt.
Astronomers enhanced the sharpness in these Advanced Camera for Surveys images to bring out features on Ceres' surface, including brighter and darker regions that could be asteroid impact features.
The observations were made in Visible and UV Light between December 2003 and January 2004.
The colors represent the differences between relatively red and blue regions. These differences may simply be due to variation on the surface among different types of material.
Ceres' round shape suggests that its interior is layered like those of terrestrial planets such as Earth. Ceres may have a rocky inner core, an icy mantle, and a thin, dusty outer crust inferred from its density and rotation rate of 9 hours. Ceres is approximately 590 miles (about 950 Km) across and was first discovered in 1801".MareKromium
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008-Ceres-Dumas_300-PCF-LXTT.jpg1-Ceres from Keck Observatory105 visitenessun commentoMareKromium
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009-1-Ceres-PIA19884-PCF-LXTT-IPF-1.jpgWhite Unnamed Crater on 1-Ceres (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)61 visiteToday's APOD is an Extra Detail Magnification (or "EDM", for short) of yesterday's Contextual (or "CTX", for short) Frame, taken by the NASA - Dawn Spacecraft that shows us a small White Crater (---> also informally known as "White Spot") that is located in the Northern Hemisphere of the Dwarf Planet named 1-Ceres.
Now, we ask you one (extremely complicated, in fact) question that you, however, should try to answer: why, on 1-Ceres, the huge and deep Impact Craters do not show "White Material" inside them, while, on the other hand, the small and shallow ones (Impact Craters) do? Probably because, but we, as IPF, cannot be sure of this (just like everyone else), the White Material, in the end, does not belong to/comes from the Sub-Surface of 1-Ceres (as we thought, at the beginning), but it belongs to/comes from the Impactors. And you, what do you think?...If you want to share your opinion, please, write us at alphacentauri@intercom.it
The picture was taken from an altitude of approx. 915 miles (such as about 1472,5461 Km) from the Surface, with a resolution of roughly 450 feet (such as about 137,16 meters) per pixel, was taken on August 21, 2015.
This image (which is a crop taken from an Original NASA - Dawn Spacecraft's b/w and NON Map-Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 19884 - Dawn HAMO Image 8) has been additionally processed, extra-magnified to aid the visibility of the details, contrast enhanced and sharpened, Gamma corrected and then colorized (according to an educated guess carried out by Dr Paolo C. Fienga-LXTT-IPF) in Absolute Natural Colors (such as the colors that a normal human eye would actually perceive if someone were onboard the NASA - Dawn Spacecraft and then looked ahead, towards the Surface of 1-Ceres), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.MareKromium
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010-1-Ceres-PIA19898-PCF-LXTT-IPF.jpgUnnamed Crater on the Terminator of 1-Ceres (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)61 visiteThis simply beautiful Contextual (or "CTX", for short) Frame, taken by the NASA - Dawn Spacecraft on August, 26, 2015, shows us, among other interesting things, an Ancient and extremely Complex Unnamed Impact Crater (which seems to be characterized by the presence of an unusually-looking - we would say, as IPF, "columnarly-shaped", maybe? - Central Peak) that is located near the Terminator Line of the Dwarf Planet named 1-Ceres.
If you will pay attention to the frame, you might agree on the fact that the long shadows - which are very well visible all over the picture - make the whole scene - with its deeply complex Surface Details - even more suggestive.
The picture was taken from an altitude of approx. 915 miles (such as about 1472,5461 Km) from the Surface, with a resolution of roughly 450 feet (such as about 137,16 meters) per pixel, was taken on August 21, 2015.
This image (which is an Original NASA - Dawn Spacecraft's b/w and NON Map-Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 19898 - Dawn HAMO Image 20) has been additionally processed, extra-magnified to aid the visibility of the details, contrast enhanced and sharpened, Gamma corrected and then colorized (according to an educated guess carried out by Dr Paolo C. Fienga-LXTT-IPF) in Absolute Natural Colors (such as the colors that a normal human eye would actually perceive if someone were onboard the NASA - Dawn Spacecraft and then looked ahead, towards the Surface of 1-Ceres), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.MareKromium
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011-1-Ceres-Full_Rotation.gif1-Ceres: Full Rotation (GIF-Movie - Credits: NASA/JPL)103 visitenessun commentoMareKromium
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012-1-Ceres-PIA19620-PCF-LXTT-IPF.jpgHuge Mountain on 1-Ceres (Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga/Lunar Explorer Italia/Italian Planetary Foundation)66 visiteLocated just on the Limb (obviously, only from our point of view) of the so-called "Dwarf Planet" 1-Ceres, at about 7 o'clock of 1-Ceres' (highly uneven) disk, we can see - once again - the large Flat-Topped Mountain - about 3 miles (such as approx. 4,82802 Km) high, surrounded by (relatively) smooth Terrain - that we have already shown you in yesterday's APOD. Probably it is useless to say - but it is a good thing, in our opinion, as IPF, to underline this specific circumstance - the so-called Emission Angle here is very high. The "new" White Spot, as well as the white Material that we have noticed still in yesterday's APOD, are also clearly visible here, in this picture.
As we have already said in the past, also this specific frame is just one among the first snapshots coming from Dawn's second Mapping Orbit of 1-Ceres, which is carried out from an altitude of approx. 2700 miles (such as about 4345,218 Km). Even in this case, the Resolution is roughly 1400 feet (such as approx. 426,72 meters) per pixel.
The image (which is an Original NASA - Dawn Spacecraft's b/w and NON Map-Projected frame published on the NASA - Planetary Photojournal with the ID n. PIA 19587 - Dawn Survey Orbit Image 19) has been additionally processed, magnified to aid the visibility of the details, contrast enhanced and sharpened, Gamma corrected and then colorized (according to an educated guess carried out by Dr Paolo C. Fienga-LXTT-IPF) in Absolute Natural Colors (such as the colors that a normal human eye would actually perceive if someone were onboard the NASA - Dawn Spacecraft and then looked ahead, towards the Limb and Surface of 1-Ceres), by using an original technique created - and, in time, dramatically improved - by the Lunar Explorer Italia Team.MareKromium
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015-Ceres_and_Vesta.jpg4-Vesta and 1-Ceres from HST (natural colors)57 visiteThese Hubble Space Telescope images of Vesta and 1-Ceres show two of the most massive asteroids in the Asteroid Belt, a Region between Mars and Jupiter.
The images are helping astronomers plan for the Dawn spacecraft’s tour of these hefty asteroids. On July 7, 2007, NASA is scheduled to launch the spacecraft on a 4-year journey to the Asteroid Belt. Once there, Dawn will do some asteroid-hopping, going into orbit around Vesta in 2011 and Ceres in 2015. Dawn will be the first spacecraft to orbit two targets. At least 100.000 asteroids inhabit the Asteroid Belt, a reservoir of leftover material from the formation of our Solar-System planets some 4,6 Billion Years (BY) ago.MareKromium
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