asteroid

New telescope at ESO’s La Silla joins effort to protect Earth from risky asteroids

James Guilford , , , ,
La Silla Observatory
The new Test-Bed Telescope 2, a European Space Agency telescope, is housed inside the shiny white dome shown in this picture, at ESO’s La Silla Observatory in Chile. The telescope has now started operations and will assist its northern-hemisphere twin in protecting us from potentially hazardous, near-Earth objects. The domes of ESO’s 0.5 m and the Danish 0.5 m telescopes are visible in the background of this image. Credit: I. Saviane/ESO

Part of the world-wide effort to scan and identify near-Earth objects, the European Space Agency’s Test-Bed Telescope 2 (TBT2), a technology demonstrator hosted at ESO’s La Silla Observatory in Chile, has now started operating. Working alongside its northern-hemisphere partner telescope, TBT2 will keep a close eye on the sky for asteroids that could pose a risk to Earth, testing hardware and software for a future telescope network.

“To be able to calculate the risk posed by potentially hazardous objects in the Solar System, we first need a census of these objects. The TBT project is a step in that direction,” says Ivo Saviane, the site manager for ESO’s La Silla Observatory in Chile.

The project, which is a collaboration between the European Southern Observatory (ESO) and the European Space Agency (ESA), “is a test-bed to demonstrate the capabilities needed to detect and follow-up near-Earth objects with the same telescope system,” says ESA’s Head of the Optical Technologies Section Clemens Heese, who is leading this project.

Guiding the structure of the Test-Bed Telescope 2 into place
An engineer guides the telescope structure of the Test-Bed Telescope 2 carefully into place as it is lowered into its sheltering dome at ESO’s La Silla Observatory. Credit: P. Sinclaire/ESO

The 56-cm telescope at ESO’s La Silla and TBT1, its identical counterpart located at the ESA’s deep-space ground station at Cebreros in Spain, will act as precursors to the planned ‘Flyeye’ telescope network, a separate project that ESA is developing to survey and track fast-moving objects in the sky. This future network will be entirely robotic; software will perform real-time scheduling of observations and, at the end of the day, it will report the positions and other information about the objects detected. The TBT project is designed to show that the software and hardware work as expected.

“The start of observations of TBT2 at La Silla will enable the observing system to work in its intended two-telescope configuration, finally fulfilling the project’s objectives,” says Heese.

While seriously harmful asteroid impacts on Earth are extremely rare, they are not inconceivable. Earth has been periodically bombarded with both large and small asteroids for billions of years, and the 2013 Chelyabinsk meteor event, which caused some 1,600 injuries, most due to flying splinters and broken glass, further raised the public’s awareness of the threat posed by near-Earth objects. Larger objects do more damage, but are thankfully easier to spot and the orbits of known large asteroids are already thoroughly studied. However, it is estimated that there are large numbers of smaller, yet-undiscovered objects we are unaware of that could do serious damage if they were to hit a populated area.

That’s where TBT and the future planned network of Flyeye telescopes come in. Once fully operational the network’s design would allow it to survey the night sky to track fast-moving objects, a significant advancement in Europe’s capacity to spot potentially hazardous near-Earth objects.

March 8 Membership Meeting, OSIRIS-REx to Bennu!

James Guilford , , , , ,
This artist's rendering shows OSIRIS-REx spacecraft descending towards asteroid Bennu to collect a sample of the asteroid’s surface. Image Credit: NASA/Goddard/University of Arizona
This artist’s rendering shows OSIRIS-REx spacecraft descending towards asteroid Bennu to collect a sample of the asteroid’s surface. Image Credit: NASA/Goddard/University of Arizona

The February Membership Meeting of the Cuyahoga Astronomical Association (CAA) will take place Monday, February 8, from 7:30 to 9:00 p.m. via the Zoom online meeting service.

The evening’s speaker will be Jeff Woytach, retired NASA Scientist whose talk is entitled, “OSIRIS-REx: Mission to Bennu!” OSIRIS-REx is a U.S. mission to return samples from the Near Earth Asteroid Bennu to Earth, and to measure theoretical effects on the asteroid to see how its orbit is perturbed. Bennu is an Earth-crossing asteroid that has the potential to impact our planet. The presentation will talk about the accomplishments of the mission, as well as other sample return missions that have been accomplished or are on the books for the future.

Woytach, originally from Scranton, Pennsylvania, earned a Bachelor of Science in Aerospace Engineering from the Pennsylvania State University in May 1983. He joined the staff of the National Aeronautics and Space Administration’s John H. Glenn Research Center (GRC) in June 1983.

Woytach has worked on space missions launched on the Space Shuttle and the Atlas/Centaur launch vehicle, and on flight hardware for the International Space Station. He is currently the Systems Engineer for the Fission Surface Power System, which will place a nuclear fission reactor on the lunar surface. Mr. Woytach also provides systems engineering support to the Psyche mission.

Led by the Jet Propulsion Laboratory (JPL), Psyche will visit an asteroid believed to be composed entirely of metal. In addition, Jeff is the systems engineer for a small spacecraft being developed to perform ocean research for the National Oceanic Partnership Program. He is also the lead for two university student design competitions sponsored by NASA, involving teams from five U.S. universities In his spare time, Mr. Woytach enjoys space exploration history, collecting space exploration memorabilia, astronomy, and “Star Trek”. He is also the founder of the “Glenn Band,” a concert band comprised of NASA Glenn employees and retirees, their family members and students from the North Olmsted School District. Mr. Woytach and his family are residents of North Ridgeville, Ohio.

Attendees may join the Zoom meeting beginning at 7:20 p.m. the nights of CAA scheduled meetings and meetings begin at 7:30.

The evening will begin with introductions and the featured speaker followed by the monthly membership business meeting, typically concluding at about 9 p.m.. Guest attendees are welcome.

To attend:

You can either “Phone in” or watch and participate via “Zoom Video”.

Phone In:  Just dial:  1-312-626-6799  (Chicago number)

You will be required to enter our meeting number:  954 8268 6049

Zoom Video with video and audio, on your web browser. (No camera required)
https://zoom.us/j/95482686049

Or download the desktop application from: https://zoom.us/download#client_4meeting

Asteroid Hygiea could be classified as a dwarf planet

James Guilford , , , , ,

Image: Asteroid/Dwarf Planet Hygiea. Credit: ESO/P. Vernazza et al./MISTRAL algorithm (ONERA/CNRS)
A new SPHERE/VLT image of Hygiea, which could be the Solar System’s smallest dwarf planet yet. As an object in the main asteroid belt, Hygiea satisfies right away three of the four requirements to be classified as a dwarf planet: it orbits around the Sun, it is not a moon and, unlike a planet, it has not cleared the neighbourhood around its orbit. The final requirement is that it have enough mass that its own gravity pulls it into a roughly spherical shape. This is what VLT observations have now revealed about Hygiea. Credit: ESO/P. Vernazza et al./MISTRAL algorithm (ONERA/CNRS)

Astronomers using ESO’s SPHERE instrument at the Very Large Telescope (VLT) have revealed that the asteroid Hygiea could be classified as a dwarf planet. The object is the fourth largest in the asteroid belt after Ceres, Vesta and Pallas. For the first time, astronomers have observed Hygiea in sufficiently high resolution to study its surface and determine its shape and size. They found that Hygiea is spherical, potentially taking the crown from Ceres as the smallest dwarf planet in the Solar System.

As an object in the main asteroid belt, Hygiea satisfies right away three of the four requirements to be classified as a dwarf planet: it orbits around the Sun, it is not a moon and, unlike a planet, it has not cleared the neighborhood around its orbit. The final requirement is that it has enough mass for its own gravity to pull it into a roughly spherical shape. This is what VLT observations have now revealed about Hygiea.

“Thanks to the unique capability of the SPHERE instrument on the VLT, which is one of the most powerful imaging systems in the world, we could resolve Hygiea’s shape, which turns out to be nearly spherical,” says lead researcher Pierre Vernazza from the Laboratoire d’Astrophysique de Marseille in France. “Thanks to these images, Hygiea may be reclassified as a dwarf planet, so far the smallest in the Solar System.”

The team also used the SPHERE observations to constrain Hygiea’s size, putting its diameter at just over 430 km. Pluto, the most famous of dwarf planets, has a diameter close to 2,400 km, while Ceres is close to 950 km in size.

Surprisingly, the observations also revealed that Hygiea lacks the very large impact crater that scientists expected to see on its surface, the team report in the study published today in Nature Astronomy. Hygiea is the main member of one of the largest asteroid families, with close to 7,000 members that all originated from the same parent body. Astronomers expected the event that led to the formation of this numerous family to have left a large, deep mark on Hygiea.

“This result came as a real surprise as we were expecting the presence of a large impact basin, as is the case on Vesta,” says Vernazza. Although the astronomers observed Hygiea’s surface with a 95 percent coverage, they could only identify two unambiguous craters. “Neither of these two craters could have been caused by the impact that originated the Hygiea family of asteroids whose volume is comparable to that of a 100 km-sized object. They are too small,” explains study co-author Miroslav Brož of the Astronomical Institute of Charles University in Prague, Czech Republic.

The team decided to investigate further. Using numerical simulations, they deduced that Hygiea’s spherical shape and large family of asteroids are likely the result of a major head-on collision with a large projectile of diameter between 75 and 150 km. Their simulations show this violent impact, thought to have occurred about 2 billion years ago, completely shattered the parent body. Once the left-over pieces reassembled, they gave Hygiea its round shape and thousands of companion asteroids. “Such a collision between two large bodies in the asteroid belt is unique in the last 3–4 billion years,” says Pavel Ševeček, a PhD student at the Astronomical Institute of Charles University who also participated in the study.

Studying asteroids in detail has been possible thanks not only to advances in numerical computation, but also to more powerful telescopes. “Thanks to the VLT and the new generation adaptive-optics instrument SPHERE, we are now imaging main belt asteroids with unprecedented resolution, closing the gap between Earth-based and interplanetary mission observations,” Vernazza concludes.

A new pockmark on the face of Mars

James Guilford , , , , , , ,

Photo: New crater on Mars. Image Credit: NASA
A dramatic, fresh impact crater dominates this false-color image taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter on Nov. 19, 2013.

NASA-JPL: Space rocks hitting Mars excavate fresh craters at a pace of more than 200 per year, but few new Mars scars pack as much visual punch as one seen in a NASA image released February 5, 2014.

The image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter shows a crater about 100 feet (30 meters) in diameter at the center of a radial burst painting the surface with a pattern of bright and dark tones. (See a high-resolution version of the image here.)

The scar appeared at some time between imaging of this location by the orbiter’s Context Camera in July 2010 and again in May 2012. Based on apparent changes between those before-and-after images at lower resolution, researchers used HiRISE to acquire this new image on Nov. 19, 2013. The impact that excavated this crater threw some material as far as 9.3 miles (15 kilometers).

The Mars Reconnaissance Orbiter Project is managed by NASA’s Jet Propulsion Laboratory, Pasadena, Calif., for NASA’s Science Mission Directorate, Washington. JPL is a division of the California Institute of Technology in Pasadena. HiRISE is operated by the University of Arizona, Tucson. The instrument was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Malin Space Science Systems, San Diego, built and operates the Context Camera.

For more information about the Mars Reconnaissance Orbiter, which has been studying Mars from orbit since 2006, visit http://www.nasa.gov/mro .