ZZ-ZZ-ZZ-Pluto-lorri_pluto_im01_1x1_oct2007_ppt.pngPluto54 visiteThis image demonstrates the first detection of Pluto using the High-Resolution mode on the New Horizons Long-Range Reconnaissance Imager (LORRI). The mode provides a clear separation between Pluto and numerous nearby background stars. When the image was taken on October 6, 2007, Pluto was located in the constellation Serpens, in a region of the sky dense with background stars.
Typically, LORRI’s exposure time in Hi-Res mode is limited to approx. 0,1", but by using a special pointing mode that allowed an increase in the exposure time to 0,967", scientists were able to spot Pluto, which is approximately 15.000 times fainter than human eyes can detect.
New Horizons was still too far from Pluto (3,6 BKM, or 2,2 BMs) for LORRI to resolve any details on Pluto’s surface – that won’t happen until Summer 2014, approximately one year before closest approach. For now the entire Pluto System remains a bright dot to the Spacecraft’s telescopic camera, though LORRI is expected to start resolving Charon from Pluto – seeing them as separate objects – in summer 2010.MareKromium
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ZZ-ZZ-Nhsv3-060808_NHpassSaturn.jpgWhere's New Horizons? June 2008 - Full Trajectory: Overhead View54 visiteNew Horizons crossed the orbit of Saturn on June 8, passing yet another interplanetary milepost on its voyage to Pluto and the icy environs of the Kuiper Belt.
Spinning in healthy, electronic hibernation, New Horizons reached a distance of 10.06 AU (Astronomical Units; such as about 935 MMs or about 1,5 BKM) from the Sun at 10:00 UT (Universal Time), becoming the first spacecraft to journey beyond Saturn’s orbit since Voyager 2 passed the ringed planet nearly 27 years ago. In fact, Voyager 1 and 2, at the edge of the Sun’s Heliosphere some 100 AU away, are the only Spacecrafts operating farther out than New Horizons.
New Horizons reached Saturn's distance just two years and four months after launch - by far a faster transit to Saturn than any previous spacecraft. (Voyager 1, the previous record holder, made the trip in approximately three years and two months)
New Horizons has crossed the orbits of three planets since its launch in January 2006, though only one – Jupiter, in February 2007 – was close enough for a gravity boost and for the Spacecraft to study. Saturn is more than 1,4 BMs (about 2,3 BKM) from New Horizons at present.
After a productive two-week series of system checks, maintenance activities, and software and command uploads,the Spacecraft is humming through the Outer Solar System at a speed of 40.850 miles (65.740 Km) per hour. The New Horizons Team expects to keep the Spacecraft in hibernation until Sept. 2, 2008. MareKromium
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B-Caron.jpgThe Discovey of Charon54 visiteCharon was discovered in June 1978 by U.S. Naval Observatory astronomers James Christy and Robert Harrington. They weren't even looking for satellites of Pluto - they were trying to refine Pluto's orbit around the Sun!
Charon was discovered when sharp-eyed Christy noticed the images of Pluto were strangely elongated - it looked like Pluto had an irregular blob attached to its side. Perhaps the telescope was joggled when the picture was taken? No, that possibility was quickly eliminated by noticing that the other stars on the photo were round. Moreover, the blob itself seemed to move around Pluto - the direction of elongation cycled back and forth over 6.39 days - Pluto's rotation period. From this, Christy, after being checked by Harrington, concluded that Pluto either possessed a mountain thousands of kilometers high or a satellite that orbited in its synchronous orbit.
Searching through their archives of Pluto images taken years before, Christy found more cases where Pluto appeared strangely elongated. Working independently, Christy measured the angle (from north) where the elongations appeared while Harrington calculated what the answer "should be" if the elongation was caused by an orbiting satellite. When the anxious moment came for them to compare their answers, they found perfect agreement. Just to be sure, they waited for the U. S. Naval Observatory 60-inch telescope to make one more confirmation. And sure enough, on July 2 new images showed the elongation due to a satellite right where it was supposed to be. They announced their discovery to the world on July 7, 1978. Christy proposed the name "Charon", after the mythological ferryman who carried souls across the river Acheron, one of the five mythical rivers that surrounded Pluto's underworld. Apart from the mythological connection for this name, Christy chose it because the first four letters also matched the name of his wife, Charlene.
Charon's satellite status was finally confirmed when Pluto and Charon began a series of mutual eclipses in 1985. Later, Hubble Space Telescope and even advanced ground-based telescopes were able to spot Charon orbiting nearby — just 1/4000th of a degree from Pluto!MareKromium
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C-Pluto_Charon.jpgPluto and Charon, from the Subaru Telescope54 visiteThe excellent quality of its 8,3-meter primary mirror and the stability of the atmosphere above Mauna Kea, Hawaii, allowed the Subaru Telescope to provide clearly separated images of Pluto and Charon using its Cooled Infrared Spectrograph/Camera.
This image is produced from three 2-second exposures taken through infrared filters on June 9, 1999.
MareKromium
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