JPL Round-Up: Big Asteroid, Small Stars

Asteroid: The Movie, Part Two

As far as asteroid movies go, the sequel is better than the original. Scientists have released a more refined, longer radar movie clip of asteroid 2005 YU55, which in 2011 orbited closer to Earth than it had for at least 200 years.

The movie images were generated using data collected by the 230-foot-wide Deep Space Network antenna in Goldstone, CA. Each of the movie’s 28 frames required 20 minutes of data collected by the Deep Space Network’s radar. The data was captured between 11:24 a.m. and 1:35 p.m. PST on Nov. 7, while 2005 YU55 was approximately 860,000 miles from Earth.

Scientists using the Goldstone data were able to capture images with a resolution of four meters – five times finer than previously obtained images.

The Deep Space Network is used by NASA’s Near Earth Object Observation Program, which locates and tracks asteroids and other such pieces of space material that could pose a potential hazard to Earth. Commonly known as “Spaceguard,” the program is managed by .

The movie can be viewed online. To learn more about asteroids and near-earth objects, visit JPL’s asteroid watch page. More information about the Deep Space Network can be found at JPL’s Deep Space website.

Mars Mission Launch Tweet Up

NASA is preparing for a Thanksgiving week Tweet Up spanning two days and culminating with the launch of the Mars Science Laboratory’s Curiosity rover aboard an Atlas V rocket at Cape Canaveral Air Force Station.

Beginning at 8 a.m. PST Wednesday, Nov. 23, NASA Tweetup attendees will talk with scientists, program directors and engineers involved with the Mars Exploration program. The Tweetup will be broadcast online. Participants will tour Kennedy Space Center and Cape Canaveral and speak with administrators, astronaut Doug Wheelock, and Bill Nye the Science Guy.

The car-sized Curiosity rover is tasked with investigating a selected area of Mars where scientists believe environmental conditions could be favorable for supporting microbial life and evidence of such life – if it existed - could be preserved. The launch window opens at 7:25 a.m. PST Friday, Nov. 25 and Curiosity is set to arrive at Mars’ Gale Crater in August 2012 where it will rove for two years. JPL will manage the mission. Curiosity was designed and built at JPL.

To learn more about the Mars Curiosity rover, visit JPL’s rover webpage and Mars webpage. To connect with NASA on Twitter, visit NASA’s social networking connection site. Watch the Tweet Up and launch at UStream.

Not Big Stars Anymore

Using computers as Petri dishes, astronomers grew stars in conditions mimicking those of our primordial universe. What they found is that the very first stars in our universe were not the giants scientists had believed existed.

Scientists had widely believed that the first stars were gigantic masses hundreds of times bigger than our sun, but the results of the computer-growing experiment showsour first stars were only about tens of times more massive than the sun.

How the first stars formed out of the hydrogen and helium atoms of the early universe remain a mystery, but scientists have now learned through simulations that matter located near forming stars heats up to temperatures much higher than previously suspected, up to 90,000 degrees Fahrenheit – 8.5 times hotter than the surface temperature of our sun. According to a JPL press release, “gas this hot expands and escapes the gravity of the developing star, instead of falling back down onto it,” resulting in the star’s growth halting earlier than previously predicted and creating smaller stars.

"This is definitely going to surprise some folks," said Harold Yorke, an astronomer at JPL and co-author of the study, in a JPL press release. "It was standard knowledge until now that the first stars had to be extremely massive."

To learn more about stars, the creation of stars and our universe and JPL, visit JPL’s website.