USGS Astrogeology Hot Topics

The following names have been approved for four satellites of Neptune:

Neptune IX (Halimede)

Neptune XI (Sao)

Neptune XII (Laomedeia)

Neptune XIII (Neso)

More information about these names can be found on the Planet and Satellite Names and Discoverers page in the Gazetteer of Planetary Nomenclature.

Posted by Jennifer Blue in Planetary Nomenclature at 08:07

The Gazetteer of Planetary Nomenclature now contains images showing the recently approved names on Phobos.

Posted by Jennifer Blue in Planetary Nomenclature at 07:31

DISR view of Titan’s surface from 8 kilometres altitude

Image Credit: ESA/NASA/Univ. of Arizona

Two years ago, planetary scientists across the world watched as Europe and the US did something amazing. The Huygens descent module drifted down through the hazy atmosphere of Saturn's moon Titan, beaming its data back to Earth via the Cassini mothership. Today, Huygens's data are still continuing to surprise researchers. Titan holds a unique place in the Solar System. It is the only moon covered in a significant atmosphere. The atmosphere has long intrigued scientists as it may be similar to that of the early Earth but the deeper mystery was: what lies beneath the haze?

Huygens parachuted to the surface of Titan on 14 January 2005. While Cassini keeps flying by this moon of Saturn collecting new amazing data, one can say that the data collected by Huygens’s six instruments during its 2.5-hour descent and touch-down have provided the most spectacular view of this world yet and first dramatic change in the way we now think about it.

More: ESA - Huygens’s second landing anniversary – the surprises continue

Link: USGS - Cassini Mission

Posted by BlogAdmin in Cassini at 11:49

Close-up of the Pathfinder Mission landing site.

Image credit: NASA/JPL/Univ. of Arizona

Browse Image | Medium Image (67 kB) | Large (579 kB)

Using the high-resolution camera, HiRISE, on the Mars Reconnaissance Orbiter (MRO) spacecraft, visual clues such as peaks and craters seen in earlier images, and old-fashioned detective skills, scientists were able to identify the landing site for the 1997 Pathfinder mission's rover Sojourner within a vast landscape of seemingly homogenous Martian terrain.

More: NASA - Pathfinder landing site images from MRO HiRISE camera - several more images, include close-up images showing Pathfinder mission hardware on the surface, landing site topography, and a panorama of the landing site as seen by the lander

Link: MRO HiRISE - see more fantastic images of Mars collected by this camera

Link: USGS Astrogeology and the Mars Reconnaissance Orbiter using HiRISE - learn more about the our involvement in this mission

Posted by BlogAdmin in MRO at 16:34

Comet McNaught from Hammerfest, Norway Jan. 6, 2007.

Credit: Roger Johansen

Instructions for viewing the comet in the morning from Spaceweather.com:

1. At dawn, go outside and face east
2. Using binoculars, scan the horizon
3. The comet is located just south of due east

1. At sunset, go outside and face west
2. Using binoculars, scan the horizon
3. The comet is located low and to the right of Venus
4. A clear view of the horizon is essential

More: NASA - A Bright Comet is Coming - information about Comet McNaught

More: Spaceweather.com - Comet McNaught Photo Gallery

Posted by BlogAdmin in Sky Watching at 16:22

After nine years of operation, contact with the Mars Global Surveyor (MGS) orbiter was lost in November 2006. MGS was the first in a series of spacecraft destined for Mars. It was in a near-polar orbit on a mission to globally map the planet, examining the planet's ionosphere, atmosphere, surface, and interior using six science instruments. Designed to study Mars from orbit for two years, it accomplished many important discoveries during nine years in orbit. On Nov. 2, 2006, the spacecraft transmitted information that one of its arrays was not pivoting as commanded. Loss of signal from the orbiter began on the following orbit.

According to a NASA Watch report, in a meeting of the Mars Exploration Program Analysis Group (MEPAG), NASA's John McNamee (Mars Exploration Program) stated "We think that the failure was due to a software load we sent up in June of last year. This software tried to synch up two flight processors. Two addresses were incorrect - two memory addresses were over written. As the geometry evolved, we drove the [solar] arrays against a hard stop and the spacecraft went into safe mode. The radiator for the battery pointed at the sun, the temperature went up, and battery failed. But this should be treated as preliminary."

An internal review board will review the events to determine what caused the MGS failure, and make recommendations for future missions.

More: NASA - Panel Will Study Mars Global Surveyor Events

More: NASA Watch - MEPAG Blog, Day One

Link: NASA Mars Exploration Program Analysis Group (MEPAG)

Posted by BlogAdmin in Mars Global Surveyor at 10:54

The existence of oceans or lakes of liquid methane on Saturn's moon Titan was predicted more than 20 years ago. But with a dense haze preventing a closer look it has not been possible to confirm their presence. Until the Cassini flyby of July 22, 2006, that is.

Radar imaging data from the flyby, published this week in the journal Nature, provide convincing evidence for large bodies of liquid. This image, used on the journal's cover, gives a taste of what Cassini saw. Intensity in this colorized image is proportional to how much radar brightness is returned, or more specifically, the logarithm of the radar backscatter cross-section. The colors are not a representation of what the human eye would see.

The lakes, darker than the surrounding terrain, are emphasized here by tinting regions of low backscatter in blue. Radar-brighter regions are shown in tan. The strip of radar imagery is foreshortened to simulate an oblique view of the highest latitude region, seen from a point to its west.

This radar image was acquired by the Cassini radar instrument in synthetic aperture mode on July 22, 2006. The image is centered near 80 degrees north, 35 degrees west and is about 140 kilometers (84 miles) across. Smallest details in this image are about 500 meters (1,640 feet) across.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm .

Link: USGS - Cassini Mission

Credit: NASA/JPL/USGS

Posted by in Cassini at 13:36

Something from space disintegrated over Denver, Colorado, this morning around 6:20 am MST (1320 UT). Witnesses describe it as "brilliant, slow, twinkling, sparkly and full of rainbow colors." It was not a meteor. The fireball was the decaying body of a Soyuz U rocket that launched the French COROT space telescope on Dec. 27th. The re-entry caused no damage on the ground--just a beautiful display in the sky.

Story Credit: Spaceweather.com, January 4, 2007

More: Cloudbait Observatory January 4, 2007 Fireball

Link: CNES - COROT Space Telescope

Posted by BlogAdmin in Sky Watching at 13:57

"On Dec. 14, 2006, we observed at least five Geminid meteors hitting the Moon," reports Bill Cooke of NASA's Meteoroid Environment Office in Huntsville, AL. Each impact caused an explosion ranging in power from 50 to 125 lbs of TNT and a flash of light as bright as a 7th-to-9th magnitude star.

The explosions occurred while Earth and Moon were passing through a cloud of debris following near-Earth asteroid 3200 Phaethon. This happens every year in mid-December and gives rise to the annual Geminid meteor shower: Streaks of light fly across the sky as rocky chips of Phaethon hit Earth's atmosphere. It's a beautiful display.

More: Science@NASA - Lunar Geminids

Posted by BlogAdmin in Sky Watching at 13:54

Life is tough for a humble grain of dirt on the surface of the Moon. It's peppered with cosmic rays, exposed to solar flares, and battered by micrometeorites--shattered, vaporized and re-condensed countless times over the billions of years. Adding insult to injury, Earthlings want to strip it down to oxygen and other elements for "in situ resource utilization," or ISRU, the process of living off the land when NASA returns to the Moon in the not-so-distant future.

Living with moondust and striping it down may be trickier than anyone supposes. To find out how tricky, researchers would like to test their ideas for ISRU and their designs for lunar rovers on real lunar soil before astronauts return to the Moon. However, such testing requires tons of lunar material. Since large quantities of lunar material aren't available here on Earth, researchers at NASA's Space Flight Center are working on developing material which simulates lunar material.

More: Science@NASA - True Fakes: Scientists make simulated lunar soil

Posted by BlogAdmin in Manned Missions at 13:47