ASU Graduate Discovers New Asteroid
February 03, 2011
Finding an asteroid is easy. Finding a new asteroid is a bit more time consuming.
It took Angelo State University graduate Douglas Parsons five hours imaging the night sky with a 41-inch telescope at Stephen F. Austin University’s observatory.
Parsons is a second year graduate student at SFAU, studying physics and astronomy. He received his undergraduate physics degree at ASU in 2008. He discovered the new asteroid, which is dimmer than Pluto, on Dec. 7 while taking pictures of the Crab Nebula, listed as Messier Object I.
“We’d been working at taking images of all the Messier objects, just because we can and we really want to,” Parsons said.
Messier objects are astronomical objects compiled by French astronomer Charles Messier in 1771. The original list, composed of 103 objects, has since expanded to include 110 objects visible with small telescopes. They have comet-like appearances, but are not comets.
Parsons and fellow physic student Collin Timmons arrived at the SFAU observatory at 7 p.m. on Dec. 7.
“It was just after it had gotten really good and dark, after astronomical twilight,” Parsons said.
Astronomical twilight is approximately one or one-and-a-half hours after sunset. Originally, Parsons had planned on using the observatory’s 18-inch telescope, but problems with the dome’s shutter required him to use the 41-inch telescope.
“It was serendipitous,” he said.
The students finished their pictures taking around 4:30-5 a.m. the following morning, but did not discover the asteroid until later that day when they began stacking the images to obtain a clear, color image of the Crab Nebula.
“There are two methods for putting images together,” Parsons said. “We stack images so all the images line up. Objects that are not moving stack continuously. ‘Noise,’ however, disappears, as do small moving objects.”
“Out of habit, I took one set of images that didn’t involve a color filter, and instead of stacking them, I ‘blinked’ them,” he added.
The blinking technique permits astronomers to rapidly switch from viewing one photograph to viewing another, catching movement across the field of images.
“If something is moving, it won’t be washed out,” Parsons said. “I didn’t know what it was at first. It looked like a star in the still images, and I wasn’t paying attention to where the ‘star’ was.”
Parsons said he thought it “kind of odd” when he blinked the images. He determined it was an asteroid by how slow it was moving.
“The size of the nebula is really tiny across, taking up a small portion of the sky,” he said. “The asteroid moved a quarter of the way across the nebula in five hours.”
Parsons’ discovery was confirmed by Harvard University’s IAU Minor Planet Center. Although the asteroid was sighted previously in 2006, the observer did not have enough data points and information to calculate the orbital parameters.
“We got the discovery because we have more data to give and more accumulated data points,” Parsons said.
Timmons, a first year graduate student at SFAU, received observer credit.
“Everybody else knew before I did,” Parsons said. “Dr. Dan Burton (professor of physics) got the e-mail before I did. I was doing a planetarium show and they couldn’t get in touch with me.”
Parsons said he would like to keep tracking the asteroid and be able to find it repeatedly without difficulty. Once the asteroid is in opposition to the sun four times, Parsons will have the opportunity to name the asteroid, which has a four-year orbit.
Parsons says he likes the “depth of astronomy.”
“I can spend all my life looking and observing, and I’m always going to see cool things,” he said.