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Cassini Sends Final Close Views Of Odd Moon Hyperion
Image credit: NASA/JPL-Caltech/Space Science Institute
NASA’s Cassini spacecraft has returned images from its final close approach to Saturn’s oddball moon Hyperion, upholding the moon’s reputation as one of the most bizarre objects in the solar system. The views show Hyperion’s deeply impact-scarred surface, with many craters displaying dark material on their floors.
During this flyby, Cassini passed Hyperion at a distance of about 21,000 miles (34,000 kilometers) at closest approach. Cassini’s closest-ever Hyperion flyby took place on Sept. 26, 2005, at a distance of 314 miles (505 kilometers).
Hyperion is the largest of Saturn’s irregular, or potato-shaped, moons and may be the remnant of a violent collision that shattered a larger object into pieces. Cassini scientists attribute Hyperion’s peculiar, sponge-like appearance to the fact that it has an unusually low density for such a large object — about half that of water. Its low density indicates Hyperion is quite porous, with weak surface gravity. These characteristics mean impactors tend to compress the surface, rather than excavating it, and most material that is blown off the surface never returns.
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Ceres Animation Showcases Bright Spots
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
The mysterious bright spots on the dwarf planet Ceres are better resolved in a new sequence of images taken by NASA’s Dawn spacecraft on May 3 and 4, 2015. The images were taken from a distance of 8,400 miles (13,600 kilometers). The animation is available at:
http://www.jpl.nasa.gov/spaceimages/details.php?id=pia19547
In this closest-yet view, the brightest spots within a crater in the northern hemisphere are revealed to be composed of many smaller spots. However, their exact nature remains unknown.
“Dawn scientists can now conclude that the intense brightness of these spots is due to the reflection of sunlight by highly reflective material on the surface, possibly ice,” said Christopher Russell, principal investigator for the Dawn mission from the University of California, Los Angeles.
Dawn Glimpses Ceres’ North Pole
Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
After spending more than a month in orbit on the dark side of dwarf planet Ceres, NASA’s Dawn spacecraft has captured several views of the sunlit north pole of this intriguing world. These images were taken on April 10 from a distance of 21,000 miles (33,000 kilometers), and they represent the highest-resolution views of Ceres to date.
Subsequent images of Ceres will show surface features at increasingly better resolution.
Dawn arrived at Ceres on March 6, marking the first time a spacecraft has orbited a dwarf planet. Previously, the spacecraft explored giant asteroid Vesta for 14 months from 2011 to 2012. Dawn has the distinction of being the only spacecraft to orbit two extraterrestrial targets.
Asteroid To Fly By Earth Safely On January 26
Image credit: NASA/JPL-Caltech
An asteroid, designated 2004 BL86, will safely pass about three times the distance of Earth to the moon on January 26. From its reflected brightness, astronomers estimate that the asteroid is about a third of a mile (0.5 kilometers) in size. The flyby of 2004 BL86 will be the closest by any known space rock this large until asteroid 1999 AN10 flies past Earth in 2027.
At the time of its closest approach on January 26, the asteroid will be approximately 745,000 miles (1.2 million kilometers) from Earth.
“Monday, January 26 will be the closest asteroid 2004 BL86 will get to Earth for at least the next 200 years,” said Don Yeomans, who is retiring as manager of NASA’s Near Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California, after 16 years in the position. “And while it poses no threat to Earth for the foreseeable future, it’s a relatively close approach by a relatively large asteroid, so it provides us a unique opportunity to observe and learn more.”
Dawn Spacecraft Begins Approach To Dwarf Planet Ceres
Artist’s concept. Image credit: NASA/JPL-Caltech
NASA’s Dawn spacecraft has entered an approach phase in which it will continue to close in on Ceres, a Texas-sized dwarf planet never before visited by a spacecraft. Dawn launched in 2007 and is scheduled to enter Ceres orbit in March 2015.
Dawn recently emerged from solar conjunction, in which the spacecraft is on the opposite side of the sun, limiting communication with antennas on Earth. Now that Dawn can reliably communicate with Earth again, mission controllers have programmed the maneuvers necessary for the next stage of the rendezvous, which they label the Ceres approach phase. Dawn is currently 400,000 miles (640,000 kilometers) from Ceres, approaching it at around 450 miles per hour (725 kilometers per hour).
The spacecraft’s arrival at Ceres will mark the first time that a spacecraft has ever orbited two solar system targets. Dawn previously explored the protoplanet Vesta for 14 months, from 2011 to 2012, capturing detailed images and data about that body.
How To Target An Asteroid
Image credit: NASA/JPL-Caltech/UMD
Like many of his colleagues at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., Shyam Bhaskaran is working a lot with asteroids these days. And also like many of his colleagues, the deep space navigator devotes a great deal of time to crafting, and contemplating, computer-generated 3-D models of these intriguing nomads of the solar system.
But while many of his coworkers are calculating asteroids’ past, present and future locations in the cosmos, zapping them with the world’s most massive radar dishes, or considering how to rendezvous and perhaps even gently nudge an asteroid into lunar orbit, Bhaskaran thinks about how to collide with one.
“If you want to see below the surface of an asteroid, there’s no better way than smacking it hard,” said Bhaskaran. “But it’s not that easy. Hitting an asteroid with a spacecraft traveling at hypervelocity is like shooting an arrow at a target on a speeding race car.
“Most of the hypervelocity impact scenarios that I simulate have spacecraft/asteroid closure rates of around eight miles a second, 30,000 miles per hour [about 48,000 kilometers per hour],” said Bhaskaran.
Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-138
Building The Massive Simulation Sets Essential To Planck Results
To make the most precise measurement yet of the cosmic microwave background (CMB) – the remnant radiation from the big bang – the European Space Agency’s (ESA’s) Planck satellite mission has been collecting trillions of observations of the sky since the summer of 2009. On March 21, 2013, ESA and NASA, a major partner in Planck, will release preliminary cosmology results based on Planck’s first 15 months of data. The results have required the intense creative efforts of a large international collaboration, with significant participation by the U.S. Planck Team based at NASA’s Jet Propulsion Laboratory (JPL).
Strength in data analysis is a major U.S. contribution, including the resources of the U.S. Department of Energy’s National Energy Research Scientific Computing Center (NERSC) at Lawrence Berkeley National Laboratory and the expertise of scientists in Berkeley Lab’s Computational Cosmology Center (C3).
The cosmological signal in the CMB data set is tiny, and separating it from the overwhelming instrument noise and astrophysical foregrounds requires enormous data sets – Planck’s 72 detectors gather 10,000 samples per second as they sweep over the sky – and exquisitely precise analyses.
Full Story: http://newscenter.lbl.gov/news-releases/2013/03/14/massive-planck-simulations/
NASA’s Big Mars Rover Makes First Use Of Its Brush
Patch of rock cleaned. Image Credit: NASA/JPL-Caltech/MSSS
NASA’s Mars rover Curiosity has completed first-time use of a brush it carries to sweep dust off rocks. Nearing the end of a series of first-time uses of the rover’s tools, the mission has cleared dust away from a targeted patch on a flat Martian rock using the Dust Removal Tool.
The tool is a motorized, wire-bristle brush designed to prepare selected rock surfaces for enhanced inspection by the rover’s science instruments. It is built into the turret at the end of the rover’s arm. In particular, the Alpha Particle X-ray Spectrometer and the Mars Hand Lens Imager, which share the turret with the brush and the rover’s hammering drill, can gain information after dust removal that would not be accessible from a dust-blanketed rock.
Choosing an appropriate target was crucial for the first-time use of the Dust Removal Tool. The chosen target, called “Ekwir_1,” is on a rock in the “Yellowknife Bay” area of Mars’ Gale Crater. The rover team is also evaluating rocks in that area as potential targets for first use of the rover’s hammering drill in coming weeks.
Full Story/Links to Photos: http://www.jpl.nasa.gov/news/news.php?release=2013-009
NASA Celebrates 50 Years Of Planetary Exploration
Fifty years ago on a mid-December day, NASA’s Mariner 2 spacecraft sailed close to the shrouded planet Venus, marking the first time any spacecraft had ever successfully made a close-up study of another planet. The flyby, 36 million miles (58 million kilometers) away from Earth, gave America its first bona fide space “first” after five years in which the Soviet Union led with several space exploration milestones. Designed and built by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., the successful Mariner 2 spacecraft ushered in a new era of solar system exploration.
“JPL has always attempted to do mighty things on behalf of NASA and our nation,” said JPL director Charles Elachi. “Achieving America’s first ‘first in space’ is among the lab’s proudest achievements.”
In celebration of the anniversary, an interactive presentation highlighting 50 years of planetary exploration is available online.
Full Story: http://www.jpl.nasa.gov/news/news.php?release=2012-395
Online Presentation: http://www.jpl.nasa.gov/50years/
NASA Jet Propulsion Laboratory Selects UT Austin As Research And Education Partner
The NASA Jet Propulsion Laboratory has selected The University of Texas at Austin for its Strategic University Research Partnership program — a federally funded program focused on advancing space exploration.
The partnership will enable the university and JPL researchers to propose collaborative research and educational projects in strategic focus areas such as robotics, nanosatellites and high-precision mapping. The program also creates an employment pipeline for JPL’s future workforce.
The University of Texas at Austin is one of 12 universities that have been selected for this partnership.
Full Story: http://www.engr.utexas.edu/news/7417-nasapartnership
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