Posted on by Ken Kremer

Dawn Begins Approach to Asteroid Vesta and Snaps First Images

Dawn's First Glimpse of Vesta – Processed. This image, processed to show the true size of the giant asteroid Vesta, shows Vesta in front of a spectacular background of stars. It was obtained by the framing camera aboard NASA's Dawn spacecraft on May 3, 2011, from a distance of about 1.2 million kilometers (750,000 miles). Since Vesta is so bright that it outshines its starry background, Dawn team members commanded a long exposure time to make the stars visible. They corrected the resulting exaggerated size of Vesta by superimposing a short exposure image of the target asteroid, showing its true size. Vesta is the small, bright pearl in the middle of the image. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

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NASA’s revolutionary Dawn Asteroid Orbiter has begun the final approach phase to the giant asteroid Vesta and snapped its first science image. The image was taken on May 3, when Dawn was approximately 1.21 million kilometers (752,000 miles) distant from Vesta using the science imager known as the Framing Camera.

Besides the pure delight of seeing Vesta up close for the first time, the images play a crucial role in navigating Dawn precisely through space and successfully achieve orbit around the protoplanet that nearly formed into a full fledged planet.

Vesta is the second most massive object in the Asteroid Belt and is 530 kilometers (330 miles) in diameter.

Dawn launch on September 27, 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer

Dawn should be captured into orbit about Vesta around July 16 as the engineering team works to maneuver the spacecraft to match the asteroids path around the sun using the exotic ion thrusters. Using the background stars in the framing camera images, they will be able to determine Dawn’s location in space relative to the stars in order to precisely navigate the spacecrafts trajectory towards Vesta.

“After plying the seas of space for more than a billion miles, the Dawn team finally spotted its target,” said Carol Raymond, Dawn’s deputy principal investigator at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “This first image hints of detailed portraits to come from Dawn’s upcoming visit.”

The best images of Vesta to date were taken by the Hubble Space Telescope. Jim Adams, Deputy Director of Planetary Science, told me that the images from Dawn’s Framing Camera will exceed those from Hubble in a few weeks.

Dawn will initially enter a highly elliptical polar orbit around Vesta and start collecting science data in August from an altitude of approximately 1,700 miles (2,700 kilometers). The orbit will be lowered in stages to collect high resolution data as Dawn spends about a year collecting data from its three science instruments.

Dawn's First Glimpse of Vesta -- Unprocessed
This image shows the first, unprocessed image obtained by NASA's Dawn spacecraft of the giant asteroid Vesta in front of a background of stars. It was obtained by Dawn's framing camera on May 3, 2011, from a distance of about 1.2 million kilometers (750,000 miles). Vesta is inside the white glow at the center of the image. The giant asteroid reflects so much sunlight that its size is dramatically exaggerated at this exposure. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Thereafter Dawn will be targeted to Ceres, the largest object in the Asteroid Belt which it will reach in 2015.

Dawn is an international mission.

The framing cameras have been developed and built under the leadership of the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany, with significant contributions by the German Aerospace Center (DLR) Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The framing camera project is funded by the Max Planck Society, DLR, and NASA.

The Visible and Infrared mapping camera was provided by the Italian Space Agency. The Gamma Ray Detector was supplied by Los Alamos National Labotatory.

Read more about Dawn in my prior story:
Revolutionary Dawn Closing in on Asteroid Vesta with Opened Eyes

Dawn spacecraft under construction in cleanroom. Picture shows close up view of two science instrument; the twin Framing Cameras at top (white rectangles) and VIR Spectrometer at right. Credit: Ken Kremer

Posted on by Ken Kremer

Solar Powered Jupiter bound JUNO lands at Kennedy Space Center for blastoff

The Juno spacecraft passes in front of Jupiter in this artist's depiction. Juno, the second mission in NASA's New Frontiers program, will improve our understanding of the solar system by advancing studies of the origin and evolution of Jupiter. The spacecraft will carry eight instruments to investigate the existence of a solid planetary core, map Jupiter's intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet's auroras. Credit: NASA/JPL-Caltech

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Juno, NASA’s next big mission bound for the outer planets, has arrived at the Kennedy Space Center to kick off the final leg of launch preparations in anticipation of blastoff for Jupiter this summer.

The huge solar-powered Juno spacecraft will skim to within 4800 kilometers (3000 miles) of the cloud tops of Jupiter to study the origin and evolution of our solar system’s largest planet. Understanding the mechanism of how Jupiter formed will lead to a better understanding of the origin of planetary systems around other stars throughout our galaxy.

Juno will be spinning like a windmill as it fly’s in a highly elliptical polar orbit and investigates the gas giant’s origins, structure, atmosphere and magnetosphere with a suite of nine science instruments.

Technicians at Astrotech's payload processing facility in Titusville, Fla. secure NASA's Juno spacecraft to the rotation stand for testing. The solar-powered spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins. Credit: NASA/Jack Pfaller

During the five year cruise to Jupiter, the 3,600 kilogram probe will fly by Earth once in 2013 to pick up speed and accelerate Juno past the asteroid belt on its long journey to the Jovian system where it arrives in July 2016.

Juno will orbit Jupiter 33 times and search for the existence of a solid planetary core, map Jupiter’s intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet’s auroras.

The mission will provide the first detailed glimpse of Jupiter’s poles and is set to last approximately one year. The elliptical orbit will allow Juno to avoid most of Jupiter’s harsh radiation regions that can severely damage the spacecraft systems.

Juno was designed and built by Lockheed Martin Space Systems, Denver, and air shipped in a protective shipping container inside the belly of a U.S. Air Force C-17 Globemaster cargo jet to the Astrotech payload processing facility in Titusville, Fla.

Juno undergoes acoustics testing at Lockheed Martin in Denver where the spacecraft was built. Credit: NASA/JPL-Caltech/Lockheed Martin

This week the spacecraft begins about four months of final functional testing and integration inside the climate controlled clean room and undergoes a thorough verification that all its systems are healthy. Other processing work before launch includes attachment of the long magnetometer boom and solar arrays which arrived earlier.

Juno is the first solar powered probe to be launched to the outer planets and operate at such a great distance from the sun. Since Jupiter receives 25 times less sunlight than Earth, Juno will carry three giant solar panels, each spanning more than 20 meters (66 feet) in length. They will remain continuously in sunlight from the time they are unfurled after launch through the end of the mission.

“The Juno spacecraft and the team have come a long way since this project was first conceived in 2003,” said Scott Bolton, Juno’s principal investigator, based at Southwest Research Institute in San Antonio, in a statement. “We’re only a few months away from a mission of discovery that could very well rewrite the books on not only how Jupiter was born, but how our solar system came into being.”

Juno is slated to launch aboard the most powerful version of the Atlas V rocket – augmented by 5 solid rocket boosters – from Cape Canaveral, Fla. on August 5. The launch window extends through August 26. Juno is the second mission in NASA’s New Frontiers program.

NASA’s Mars Curiosity Rover will follow Juno to the Atlas launch pad, and is scheduled to liftoff in late November 2011. Read my stories about Curiosity here and here.

Because of cuts to NASA’s budget by politicians in Washington, the long hoped for mission to investigate the Jovian moon Europa may be axed, along with other high priority science missions. Europa may harbor subsurface oceans of liquid water and is a prime target in NASA’s search for life beyond Earth.

Technicians inside the clean room at Astrotech in Titusville, Fla. guide NASA's Juno spacecraft, as it is lowered by overhead crane, onto the rotation stand for testing. Credit: NASA/Jack Pfaller
Technicians at Astrotech unfurl solar array No. 1 with a magnetometer boom that will help power NASA's Juno spacecraft on a mission to Jupiter. Credit: NASA
Juno's interplanetary trajectory to Jupiter. Juno will launch in August 2011 and fly by Earth once in October 2013 during its 5 year cruise to Jupiter. Click to enlarge. Credit: NASA/JPL
Posted on by Nicholos Wethington

Dawn Takes up Residence in Asteroid Belt

The Dawn spacecraft – which is on a course to study the asteroid Vesta and dwarf planet Ceres – has taken up permanent residence in the asteroid belt as of November 13th. Dawn is officially the first human-made object to become a part of the asteroid belt, which is sandwiched between the orbits of Mars and Jupiter.Dawn didn’t move in without checking the place out first, though; this is the second visit for the craft, which remained there for 40 days in June of 2008. The lower boundary of the asteroids belt is defined as the furthest Mars gets away from the Sun during its orbit – 249,230,000 kilometers, or 154,864,000 miles.

Dawn, which was launched in September 2007, is on an eight-year, 4.9-billion kilometer (3-billion mile) journey to study the asteroid Vesta and the dwarf planet Ceres. By studying these members of the asteroid belt, NASA scientists hope to learn more about the formation of our Solar System. Because Vesta and Ceres are some of the largest members of the ring of asteroids between Mars and Jupiter, they are the most intact from when they were formed, and should act as a ‘time capsule’ to preserve information about what the early Solar System was like.

Dawn got a gravity assist from Mars in February of 2009, which propelled it past the planet and into the asteroid belt.

The spacecraft is expected to visit Vesta in August of 2011. Vesta is believed to be the source of most of the asteroid-origin meteorites that fall to ground here on Earth, and further study of the asteroid should confirm this.

In May of 2012, Dawn will make its way to Ceres, which lies further out in the asteroid belt. It will arrive there in July of 2015, where it will spend the remainder of its mission studying the icy dwarf planet, which may even have a tenuous atmosphere.

If you want to keep tabs on Dawn in its new home, the mission web site has a tool updated hourly, found here, which allows you to see where Dawn is right now. The tool includes simulated views of the Earth, Mars, Sun and Vesta from the vantage point of the spacecraft.

Source: JPL