Fly Over Vesta’s Cratered Terrain with Dawn

I’ve been waiting for nearly two months to be able to share these videos from the Dawn mission’s “flyover” views of Vesta. Scientists showed some of these incredible views at the Lunar and Planetary Science Conference in March, but couldn’t make them public until they published their work in the journal Science.

“Vesta is unlike any other object we’ve visited in the solar system,” said Dawn mission team member Vishnu Reddy at a briefing today. “We see a wide range of variation on the surface, with some areas bright as snow, and other areas as dark as coal.”

The video above is a stunningly beautiful flyover of most of Vesta. Another video, below, takes viewers on a virtual tour of Vesta’s south polar basin, the ‘snowman’ set of craters and a crater called Oppia.

Scientists said today that Vesta more closely resembles a small planet or Earth’s Moon than another asteroid, and they now have a better understanding of both Vesta’s surface and interior, and can conclusively link Vesta with meteorites that have fallen on Earth.

Continue reading “Fly Over Vesta’s Cratered Terrain with Dawn”

The Bright and Dark Side of Vesta’s Craters

[/caption]

Bright craters, dark craters… craters shaped like butterflies… they’re all represented here in a panorama made from images acquired by NASA’s Dawn spacecraft, currently in orbit around the asteroid Vesta.

I stitched two images together (using a third for gap fill-in) that were originally acquired by Dawn’s framing camera in October 2011 and released last week. Because the angle of sunlight is pretty close to straight-on, there’s not a whole lot of relief in the original images so I bumped that contrast up a bit as well, to help bring out Vesta’s terrain.

The dark crater in the center is Laelia, and it’s surrounded by smaller dark impact craters as well… most notably one that displays dramatic rays of dark material. At top right is the much larger crater Sextilia, which has bright material revealed along its inner rim.

Near the lower left edge, just horizontal from Laelia, is the butterfly-shaped Helena crater. It shows both bright and dark material, the latter of which can be seen slumping into the crater as well as outward from its rim. Helena is approximately 22 kilometers (14 miles) in diameter. (There’s a scale at the lower right showing a 10-km / 6.2-mile-wide span.)

The images were acquired during the HAMO (high-altitude mapping orbit) phase of the mission.

On Thursday, May 10, NASA will host a news conference at 11 a.m. PDT (2 p.m. EDT) to present a new analysis of the giant asteroid Vesta using data from the agency’s Dawn spacecraft. The event will be broadcast live on NASA Television and streamed on the agency’s website. For streaming video, downlink and scheduling information visit: http://www.nasa.gov/ntv.

The event will also be streamed live on Ustream with a moderated chat available at http://www.ustream.com/nasajpl2. Questions may also be asked via Twitter using the hashtag #asknasa.The event will be held at NASA Headquarters in Washington, broadcast live on NASA Television and streamed on the agency’s website. For NASA TV streaming video, downlink and scheduling information, visit: http://www.nasa.gov/ntv.

Image credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA. Edited by J. Major.

This artist's concept shows NASA's Dawn spacecraft orbiting the giant asteroid Vesta. (NASA/JPL-Caltech)

Dawn Reveals More of Vesta’s Secrets

These composite images from the framing camera aboard NASA's Dawn spacecraft show three views of a terrain with ridges and grooves near Aquilia crater in the southern hemisphere of the giant asteroid Vesta. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

[/caption]

Vesta is finally giving up its secrets, thanks to the Dawn spacecraft! The latest images sent back from Dawn are revealing new details about the giant asteroid, including its varied surface composition, sharp temperature changes and clues to its internal structure. Scientists say all the information garnered by Dawn will help us to better understand the early solar system and processes that dominated its formation.

“Dawn now enables us to study the variety of rock mixtures making up Vesta’s surface in great detail,” said Harald Hiesinger, a Dawn participating scientist at Münster University in Germany. “The images suggest an amazing variety of processes that paint Vesta’s surface.”

Images from Dawn’s framing camera and visible and infrared mapping spectrometer, taken 420 miles (680 kilometers) and 130 miles (210 kilometers) above the surface of the asteroid, show a variety of surface mineral and rock patterns. Coded false-color images help scientists better understand Vesta’s composition and enable them to identify material that was once molten below the asteroid’s surface.

Researchers also see breccias, which are rocks fused during impacts from space debris. Many of the materials seen by Dawn are composed of iron- and magnesium-rich minerals, which often are found in Earth’s volcanic rocks. Images also reveal smooth pond-like deposits, which might have formed as fine dust created during impacts settled into low regions.

These images of Tarpeia crater, near the south pole of the giant asteroid Vesta, were obtained by the visible and infrared mapping spectrometer on NASA’s Dawn spacecraft. Image credit: NASA/JPL-Caltech/UCLA/INAF

At the Tarpeia crater near the south pole of the asteroid, Dawn imagery revealed bands of minerals that appear as brilliant layers on the crater’s steep slopes. The exposed layering allows scientists to see farther back into the geological history of the giant asteroid.

The layers closer to the asteroid’s surface bear evidence of contamination from space rocks bombarding Vesta. Layers below preserve more of their original characteristics. Frequent landslides on the slopes of the craters also have revealed other hidden mineral patterns.

This colorized image from NASA’s Dawn mission shows temperature variations at Tarpeia crater, near the south pole of the giant asteroid Vesta. Image credit: NASA/JPL-Caltech/UCLA/INAF

“These results from Dawn suggest Vesta’s ‘skin’ is constantly renewing,” said Maria Cristina De Sanctis, lead of the visible and infrared mapping spectrometer team based at Italy’s National Institute for Astrophysics in Rome.

This set of images from NASA's Dawn mission shows topography of the southern hemisphere of the giant asteroid Vesta and a map of Vesta’s gravity variations that have been adjusted to account for Vesta’s shape. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn has given scientists a near 3-D view into Vesta’s internal structure. By making ultra-sensitive measurements of the asteroid’s gravitational tug on the spacecraft, Dawn can detect unusual densities within its outer layers. Data now show an anomalous area near Vesta’s south pole, suggesting denser material from a lower layer of Vesta has been exposed by the impact that created a feature called the Rheasilvia basin. The lighter, younger layers coating other parts of Vesta’s surface have been blasted away in the basin.

Dawn obtained the highest-resolution surface temperature maps of any asteroid visited by a spacecraft. Data reveal temperatures can vary from as warm as minus 10 degrees Fahrenheit (minus 23 degrees Celsius) in the sunniest spots to as cold as minus 150 degrees Fahrenheit (minus 100 degrees Celsius) in the shadows. This is the lowest temperature measurable by Dawn’s visible and infrared mapping spectrometer. These findings show the surface responds quickly to illumination with no mitigating effect of an atmosphere.

“After more than nine months at Vesta, Dawn’s suite of instruments has enabled us to peel back the layers of mystery that have surrounded this giant asteroid since humankind first saw it as just a bright spot in the night sky,” said Carol Raymond, Dawn deputy principal investigator at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “We are closing in on the giant asteroid’s secrets.”

The latest findings were presented today at the European Geosciences Union meeting in Vienna, Austria.

Source: NASA

Asteroid’s Unusual Light and Dark Crater

A 5-km-wide crater on Vesta displays light and dark material.

[/caption]

Light and dark material spreads outward from a 5-km-wide crater on Vesta in this image from NASA’s Dawn spacecraft, acquired on October 22, 2011. While craters with differently-toned materials have been previously seen on the asteroid, it is unusual to find one with such a large amount of ejecta of different albedos.

This is a crop of a larger version which was released today on the Dawn website.

This brightness image was taken through the clear filter of Dawn’s framing camera. The distance to the surface of Vesta is 700 kilometers (435 miles) and the image has a resolution of about 70 meters (230 feet) per pixel.

Orbit map: Where is Dawn now?

Vesta resides in the main asteroid belt between the orbits of Mars and Jupiter and is thought to be the source of many of the meteorites that fall to Earth. The Dawn spacecraft successfully entered orbit around Vesta on July 16, 2011.

After its investigation of Vesta, Dawn will leave orbit and move on to Ceres. It will become the first spacecraft to orbit two different worlds.

Image Credit: NASA/ JPL-Caltech/ UCLA/ MPS/ DLR/ IDA

Have a Vesta Fiesta This Weekend!

To help celebrate the start of the Dawn mission to Vesta, NASA is organizing a “Vesta Fiesta!” After traveling the solar system for nearly four years, the Dawn spacecraft is now entering the “science” phase of its mission. Given the fact that Dawn is the first spacecraft to orbit an object in the asteroid belt, a fiesta is in order! (Here in Arizona we relish ANY excuse to fiesta!) Between August 5 and August 7, 2011, Vesta Fiestas will be held to help celebrate Dawn’s arrival at Vesta.

NASA is encouraging fans of the Dawn mission to join the celebration by hosting events at local clubs, schools, museums or societies. NASA has also provided numerous resources that are free to use for Vesta Fiestas, including games and activities, media resources (invitations, audio files, observing info, etc.) and live video on August 6th from the “Flagship” celebration at JPL in Pasedena, California.

If you’d like to participate by hosting your own party, or to find a party in your area, visit this page on the Dawn website, or on Facebook at: http://www.facebook.com/event.php?eid=225252850843508

You can also follow the Dawn mission on Twitter

After studying the asteroid Vesta, Dawn will continue on to study dwarf planet Ceres, also in the main asteroid belt between Mars and Jupiter.

To help encourage participation, I humbly offer my Spicy Fiesta Cheese Dip:

Ingredients:
1lb sausage (breakfast or Italian)
1 block of Velveeta (cut into ~1 inch square cubes)
1 jar of your favorite salsa and (Optional) 1 small can (4oz?) of diced green chile peppers – Not Red Hot Chili Peppers! Flea, Chad and Anthony hate being diced.)

Procedure: Place 1/2 of the cubed Velveeta in a crock pot, set to “high”. Cook sausage and diced peppers completely in a skillet, add cooked sausage and peppers to the crock pot along with the salsa and remaining velveeta. Leave crock pot on “high” until all the Velveeta is melted, then set to “low” – stir often! Serve with tortilla chips and an ice cold drink of your choice.

If you’d like to learn more about the Dawn mission to Vesta and Ceres, you can visit the Dawn website.

Looming Larger: Dawn Approaches Vesta, Enters Orbit July 15-16

NASA's Dawn spacecraft obtained this image of the giant asteroid Vesta with its framing camera on July 9, 2011. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

[/caption]

As we anticipate the Dawn spacecraft going into orbit of Vesta within the next 36 hours, here’s the latest image taken as the spacecraft approaches Vesta, taken on July 9 from a distance of about 41,000 kilometers (26,000 miles). Surface details are coming into focus a little more than from the previous image that was released. The Dawn mission is exciting, as it will be the first spacecraft to enter orbit around a main-belt asteroid, and as we’ve said before, it will be intriguing for scientists to study this lumpy little world in detail and perhaps figuring out what Vesta really is.

Below is an “enhanced” look at this view of Vesta by Stu Atkinson.

Some astronomers classify Vesta as an asteroid, some a protoplanet, and some are on the fence. It’s not really considered a dwarf planet, but the classification could be re-evaluated when Dawn gets in orbit of Vesta and studies it in detail.

An enhanced view of Vesta from the July 9, 2011 image taken by the Dawn spacecraft. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA, enhancements by Stu Atkinson.

Stu sent us this image with the caveat that he created it for his own amusement/entertainment, and that it’s not a scientifically enhanced image — i.e., it’s not to be 100% relied upon for feature identification, etc. But it’s a little clearer and sharper than the original from NASA/JPL. Thanks Stu!

Engineers expect the spacecraft to be captured into orbit at approximately 10 p.m. PDT Friday, July 15 (1 a.m. EDT Saturday, July 16). They expect to hear from the spacecraft and confirm that it performed as planned during a scheduled communications pass that starts at approximately 11:30 p.m. PDT on Saturday, July 16 (2:30 a.m. EDT Sunday, July 17). When Vesta captures Dawn into its orbit, engineers estimate there will be approximately 9,900 miles (16,000 kilometers) between the spacecraft and Vesta. At that point, the two will be approximately 117 million miles (188 million kilometers) from Earth.

“It has taken nearly four years to get to this point,” said Robert Mase, Dawn project manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Our latest tests and check-outs show that Dawn is right on target and performing normally.”

Engineers have been subtly shaping Dawn’s trajectory for years to match Vesta’s orbit around the sun with its ion engine. Unlike other missions, where dramatic propulsive burns put spacecraft into orbit around a planet, Dawn will ease up next to Vesta. Then the asteroid’s gravity will capture the spacecraft into orbit. However, until Dawn nears Vesta and makes accurate measurements, the asteroid’s mass and gravity will only be estimates. So the Dawn team will need a few days to refine the exact moment of orbit capture.

Launched in September 2007, Dawn will depart for its second destination, the dwarf planet Ceres, in July 2012. The spacecraft will be the first to orbit two bodies in our solar system.

Stay tuned for more details and updates on the Dawn mission.

Source: JPL

Latest Image from Dawn: View of Vesta Getting Sharper

The Dawn spacecraft took this image of Vesta on July 1, 2011. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

[/caption]

The Dawn spacecraft is getting closer to asteroid/protoplanet Vesta, and the view is getting better! Here’s the latest image, which was obtained with Dawn’s framing camera on July 1, 2011 and just released today. It was taken from a distance of about 62,000 miles (100,000 kilometers). Each pixel in the image corresponds to roughly 5.8 miles (9.3 kilometers). Features like craters are starting to sharpen as the spacecraft moves closer, as well as the lumps, bumps and variations in color.

The most exciting part of this mission will be finally figuring out what Vesta really is. Here, it’s looking more like a squished version of our own Moon; a little smoother than I was expecting from some of the earlier images.

Some astronomers classify Vesta as an asteroid, some a protoplanet, and some are on the fence. It’s not really considered a dwarf planet, but the classification could be re-evaluated when Dawn gets in orbit of Vesta and studies it in detail.

Below is an “enhanced” view by Stu Atkinson:

The latest Vesta image from Dawn, with enhancements by Stu Atkinson.

Stu sent us this image with the caveat that he created it for his own amusement/entertainment, and that it’s not a scientifically enhanced image — i.e., it’s not to be 100% relied upon for feature identification, etc. But some of the craters show up a tad better.

Vesta is pretty much an enigma: too big for an asteroid and more evolved than other asteroid. But it is kind of too small for a planet (even a dwarf one). But that’s why it is so interesting so scientists and getting Dawn in orbit will be exciting.

Stay tuned for more!

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

[/caption]

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

Revolutionary Dawn Closing in on Asteroid Vesta with Opened Eyes

Virtual Vesta. Taking their best guess, the science team on NASA’s Dawn Asteroid Orbiter have created a series of still images and videos (see below) to simulate what the protoplanet Vesta might look like. The exercise was carried out by mission planners at NASA's Jet Propulsion Laboratory and science team members at the German Aerospace Center and the Planetary Science Institute. Image credit: NASA/JPL-Caltech/ESA/UCLA/DLR/PSI/STScI/UMd

[/caption]

The excitement is building as NASA’s innovative Dawn spacecraft closes in on its first protoplanetary target, the giant asteroid Vesta, with its camera eyes now wide open. The probe is on target to become the first spacecraft from Earth to orbit a body in the main asteroid belt and is set to arrive about four months from now in late July 2011.

Vesta is the second most massive object in the Asteroid Belt between Mars and Jupiter (map below). Since it is also one of the oldest bodies in our Solar System, scientists are eager to study it and search for clues about the formation and early history of the solar system. Dawn will spend about a year orbiting Vesta. Then it will fire its revolutionay ion thrusters and depart for Ceres, the largest asteroid in our solar system.

Dawn is equipped with three science instruments to photograph and investigate the surface mineralogy and elemental composition of the asteroid. The instruments were provided by the US, Germany and Italy. The spacecraft has just awoken from a six month hibernation phase. All three science instruments have been powered up and reactivated.

Dawn will image about 80 percent of Vesta’s surface at muliple angles with the onboard framing cameras to generate topographical maps. During the year in orbit, the probe will adjust its orbit and map the protoplanet at three different and decreasing altitudes between 650 and 200 kilometers, and thus increasing resolution. The cameras were provided and funded by Germany.

To prepare for the imaging campaign, mission planners from the US and Germany conducted a practice exercise to simulate the mission as though they were mapping Vesta. The effort was coordinated among the science and engineering teams at NASA’s Jet Propulsion Laboratory, the Institute of Planetary Research of the German Aerospace Center (DLR) in Berlin and the Planetary Science Institute in Tuscon, Ariz.

Simulated Vesta from the South Pole
This image shows the scientists' best guess to date of what the surface of the protoplanet Vesta might look like from the south pole, as projected onto a sphere 250 kilometers (160 miles) in radius. It was created as part of an exercise for NASA's Dawn mission involving mission planners at NASA's Jet Propulsion Laboratory and science team members at the Planetary Science Institute in Tuscon, Ariz. Credit: NASA/JPL-Caltech/UCLA/PSI

“We won’t know what Vesta really looks like until Dawn gets there,” said Carol Raymond in a NASA statement. Raymond is Dawn’s deputy principal investigator, based at JPL, who helped orchestrate the activity. “But we needed a way to make sure our imaging plans would give us the best results possible. The products have proven that Dawn’s mapping techniques will reveal a detailed view of this world that we’ve never seen up close before.”

Two teams worked independently and used different techniques to derive the topographical maps from the available data sets. The final results showed only minor differences in spatial resolution and height accuracy.

Using the best available observations from the Hubble Space Telescope and ground based telescopes and computer modeling techniques, they created maps of still images and a rotating animation (below) showing their best guess as to what Vesta’s surface actually looks like. The maps include dimples, bulges and craters based on the accumulated data to simulate topography and thus give a sense of Virtual Vesta in three dimensions (3 D).

“Working through this exercise, the mission planners and the scientists learned that we could improve the overall accuracy of the topographic reconstruction, using a somewhat different observation geometry,” said Nick Mastrodemo, Dawn’s optical navigation lead at JPL. “Since then, Dawn science planners have worked to tweak the plans to implement the lessons of the exercise.”

Dawn launch on September 27, 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer
Of course no one will know how close these educated guesses come to matching reality until Dawn arrives at Vesta.

The framing camera system consists of two identical cameras developed and built by the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany and the German Aerospace Center (DLR) in Berlin.

“The camera system is working flawlessly. The dry run was a complete success,” said Andreas Nathues, lead investigator for the framing camera at the Max Planck Institute in Katlenburg-Lindau, Germany.

Since the probe came out of hibernation, the mechanical and electrical components were checked out in mid March and found to be in excellent health and the software was updated.

Dawn is a mission of many firsts.

Dawn spacecraft under construction in Cleanroom.
Picture shows close up view of two science instruments;
The twin Framing Cameras at top (white rectangles) and VIR Spectrometer at right. Credit: Ken Kremer
The spacecraft is NASA’s first mission specifically to the Asteroid Belt. It will become the first mission to orbit two solar system bodies.

The revolutionary Dawn mission is powered by exotic ion propulsion which is vastly more efficient than chemical propulsion thrusters. Indeed the ability to orbit two bodies in one mission is only enabled via the use of the ion engines fueled by xenon gas.

Vesta and Ceres are very different worlds that orbit between Mars and Jupiter. Vesta is rocky and may have undergone volcanism whereas Ceres is icy and may even harbor a subsurface ocean conducive to life.

Dawn will be able to comparatively investigate both celestial bodies with the same set of science instruments and try to unlock the mysteries of the beginnings of our solar system and why they are so different.

Dawn is part of NASA’s Discovery program and was launched in September 2007 by a Delta II rocket from Cape Canaveral Air Force Station, Florida.

Virtual Vesta in 2 D.
This image shows a model of the protoplanet Vesta, using scientists' best guess to date of what the surface of the protoplanet might look like. The images incorporate the best data on dimples and bulges of Vesta from ground-based telescopes and NASA's Hubble Space Telescope. The cratering and small-scale surface variations are computer-generated, based on the patterns seen on the Earth's moon, an inner solar system object with a surface appearance that may be similar to Vesta. Credit: NASA/JPL-Caltech/UCLA/PSI
Virtual Vesta in 3 D.
This anaglyph -- best viewed through red-blue glasses -- shows a 3-D model of the protoplanet Vesta, using scientists' best guess to date of what the surface of the protoplanet might look like. Image credit: NASA/JPL-Caltech/UCLA/PSI
Dawn Spacecraft current location approaching Asteroid Vesta on March 21, 2011

Asteroid Might be Visible to Naked Eye on Feb. 17

Asteroid Vesta as seen by NASA's Hubble Space Telescope. Image credit: NASA/ESA/U of Md./STSci/Cornell/SWRI/UCLA

[/caption]
An asteroid could be visible with binoculars, or even the naked eye on Wednesday, February 17, 2010. No, it’s not coming close to Earth, although this second most massive object in the asteroid belt will be at its closest point to Earth in its orbit, about 211,980,000 kilometers (131,700,000 miles) away. Asteroid Vesta – one of the asteroids that the Dawn spacecraft will visit – will be at opposition on Wednesday, meaning it is opposite the sun as seen from Earth, and is closest to us. Vesta is expected to shine at magnitude 6.1, and that brightness should make it visible for those with clear skies and a telescope, but perhaps even those blessed with excellent vision and little or no light pollution. Vesta will be visible in the eastern sky in the constellation Leo, and will continue to be visible — although less so — in the coming months.

What makes this space rock so prominent these days? Along with its relative proximity at this point, a full half of the asteroid is being bathed by sunlight when seen from Earth, making it appear brighter. Another attribute working in the observer’s favor is that Vesta has a unique surface material that is not as dark as most main belt asteroids – allowing more of the sun’s rays to reflect off its surface.

For more info about observing Vesta, check out this article from Sky & Telescope.

If you get lucky enough to see Vesta, and want to learn more about it, check out this info on the Dawn mission website. Dawn is currently motoring its way through the asteroid belt, will begin its exploration of Vesta in the summer of 2011.

Source: JPL