An SUV-sized asteroid, which incidentally was the closest object to fly 2950 km above the surface of earth, was discovered on Sunday by two Indian Institute of Technology-Bombay (IIT-B) students, using data from the robotic Zwicky Transient Facility (ZTF) in California, IIT-B announced here Thursday.
Designated 2020 QG, the object --discovered by IIT-B students Kunal Deshmukh and Kritti Sharma while working on a research project --is the closest known asteroid to fly by Earth without impacting the planet. The previous known record-holder is asteroid 2011 CQ1, discovered by the Catalina Sky Survey in 2011, which passed above Earth about 1,550 miles (2,500 kilometers) higher than 2020 QG.
Sunday (August 16) was Kritti’s third day on a research project to search for Near Earth Asteroids. She and Kunal were analysing ZTF data on Sunday afternoon, when they reported five “streaks” in the data as potential asteroids. Little did they know that one of them was a record-breaking asteroid.
After the ZTF team reported their finding to the International Astronomical Union Minor Planet Center, several telescopes followed up to learn more about the asteroid's size and orbit, proving that it had passed very close to Earth.
“Helping make a discovery like this, so early in my research project, is beyond what I had ever imagined!, Kritti Sharma, the third year undergraduate student of IIT Bombay’s Department of Mechanical Engineering,
“The data looked like all other Near Earth Asteroids we have seen so far”, Kunal – a final year student in the department of Metallurgy and Materials Science at IIT Bombay, said.
Their advisor, a proud Prof. Varun Bhalerao said: “It is wonderful to see these students coming from diverse backgrounds and contributing to astrophysics research. We are very excited about our next phase: studying such objects with the robotic GROWTH-India Telescope at Hanle, Ladakh”.
Asteroid 2020 QG is about 10 to 20 feet (3 to 6 meters) across, or roughly the size of an SUV, so it was not big enough to do any damage even if it had been pointed at Earth; instead, it would have burned up in our planet's atmosphere.
“The asteroid flew close enough to Earth that Earth's gravity significantly changed its orbit,” ZTF co-investigator Tom Prince, the Ira S. Bowen Professor of Physics at Caltech and a senior research scientist at JPL that Caltech manages for NASA, said.
“The asteroid flew close enough to Earth that Earth's gravity significantly changed its orbit,” says ZTF co-investigator Tom Prince, the Ira S. Bowen Professor of Physics at Caltech and a senior research scientist at JPL, which Caltech manages for NASA.
Instances of asteroids of this size flying roughly as close to Earth as 2020 QG do occur about once a year or less, but many of them go undetected. “ZTF's large-field of view and rapid data processing allows it to find rare asteroids like this that other telescopes might not find,” George Helou, ZTF co-investigator and director of IPAC, an astronomy center, at Caltech. ZTF that is funded by the National Science Foundation (NSF) and other collaborators, said.
IPAC scans the entire northern sky every three nights in search of supernovas, erupting stars, and other objects that otherwise change or move in the sky. As part of a NASA-funded program, ZTF team members search for near-Earth asteroids.
When these space rocks speed across the sky, they leave streaks in the ZTF images. Each night, machine-learning programs automatically sort through about 100,000 images in search of these streaks, and then narrow down the best asteroid candidates to be followed up by humans. This results in about 1,000 images that team members and students sort through by eye every day
“A lot of the streaks are satellites, but we can quickly go through the best images by eye to find the actual asteroids. This latest find really demonstrates that ZTF can be used to locate objects very close to Earth that are on potentially impacting trajectories,” Bryce Bolin, postdoctoral scholar in astronomy at Caltech and a member of the ZTF team, who regularly hunts for asteroids, said.
After the ZTF team reported their finding to the International Astronomical Union Minor Planet Center, several telescopes followed up to learn more about the asteroid's size and orbit.
GROWTH-India is a partnership between the Indian Institute of Astrophysics, Bangalore and Indian Institute of Technology Bombay, with the support from the Indo-US Science and Technology Forum (IUSSTF) and the Science and Engineering Research Board (SERB) of the Department of Science and Technology (DST), Government of India. The discovery is a part of the international GROWTH collaboration.