Sunday, February 06, 2022

As evidenced by a recent Netflix movie, dangerous asteroids can come from anywhere.  So there was an obvious weakness in our asteroid defense system when only one of the hemispheres was covered by telescopes that constantly scan the sky.  That was the case until recently, with the expansion of the Asteroid Terrestrial-impact Last Alert System (ATLAS) system into the southern hemisphere.

ATLAS, funded by NASA and run by the University of Hawai’i, was originally just two telescopes set up on Haleakal? and Maunaloa, two separate parts of Hawai’i.  After becoming fully operational in 2017, the system was able to scan the sky every 24 hours, barring any cloud cover, to watch for any potential moving asteroids.   But from their vantage point, they could only scan half of the sky.  

One of the telescopes being lifted into place in South Africa.
Credit – Willie Koorts (SAAO)

NASA funded two more telescopes in the southern hemisphere to rectify that problem – one located in South Africa and one in Chile.  The one in South Africa was contracted to the South African Astronomical Observatory, while the Chilean telescope was supported by a public-private consortium that included the Millennium Institute for Astrophysics and Obstech, a company that runs a private observatory.

The Covid pandemic slowed down the installation process and bungled up some supply chains, but recently both telescopes achieved first light.  Importantly, they did so at different times of the day, allowing observes located in Hawai’i to remotely monitor the dark sky over South Africa and Chile during the daytime on their island.  

ATLAS telescope located on Maui
Credit – Henry Weiland

Those observations have already been a success, with the South African observatory identifying its first Near-Earth Object on January 22nd.  2022 BK, as it is now known, is a 100-m asteroid that poses no threat to Earth.  However, asteroids of a similar size could potentially wipe out an entire region if they impact the planet.  ATLAS would be capable of providing about three weeks warning of any asteroid large enough to cause such devastation.  Even for smaller asteroids, such as a 20-m asteroid that could wipe out a city, it was capable of providing at least 24 hours’ notice.

While that might not seem like a lot of time, it is the best system so far for providing such detections.  However, it does work with other systems, such as Pan-STARRS and the Catalina Sky Survey, to fully understand what hazardous asteroids may be in the area.  Humanity could use all the help it could get in that regard.

Learn More:
University of Hawai’i at Manoa – Expanded UH asteroid tracking system can monitor entire sky
NASA – NASA Asteroid Tracking System Now Capable of Full Sky Search
Republicworld.com – NASA’s Enhanced ATLAS Observatory To Scan Entire Sky For 24 Hrs To Track Killer Asteroids
ATLAS – Asteroid Terrestrial-impact Last Alert System   

NASA State-of-the-Art Asteroid Tracking System Now Capable of Full Sky Search

Tracking Asteroid Hitting Earth

The NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS)—a state-of-the-art asteroid detection system operated by the University of Hawai‘i (UH) Institute for Astronomy (IfA) for the agency’s Planetary Defense Coordination Office (PDCO)—has reached a new milestone by becoming the first survey capable of searching the entire dark sky every 24 hours for near-Earth objects (NEOs) that could pose a future impact hazard to Earth. Now comprised of four telescopes, ATLAS has expanded its reach to the southern hemisphere from the two existing northern-hemisphere telescopes on Haleakala and Maunaloa in Hawai‘i to include two additional observatories in South Africa and Chile.

NASA Asteroid Tracking System

From left to right: Sutherland ATLAS station during construction in South Africa. Credit: Willie Koorts (SAAO); Chilean engineers and astronomers installing the ATLAS telescope at El Sauce Observatory. Credit: University of Hawaii; Illustration of NASA’s DART spacecraft and the Italian Space Agency’s (ASI) LICIACube prior to impact at the Didymos binary system. Credit: NASA/Johns Hopkins, APL/Steve Gribben; Illustration of the NEO Surveyor spacecraft

“An important part of planetary defense is finding asteroids before they find us, so if necessary, we can get them before they get us” said Kelly Fast, Near-Earth Object Observations Program Manager for NASA’s Planetary Defense Coordination Office. “With the addition of these two telescopes, ATLAS is now capable of searching the entire dark sky every 24 hours, making it an important asset for NASA’s continuous effort to find, track, and monitor NEOs.”

UH IfA developed the first two ATLAS telescopes in Hawai‘i under a 2013 grant from NASA’s Near-Earth Objects Observations Program, now part of NASA’s PDCO, and the two facilities on Haleakala and Maunaloa, respectively, became fully operational in 2017. After several years of successful operation in Hawai‘i, IfA competed for additional NASA funds to build two more telescopes in the southern hemisphere. IfA sought partners to host these telescopes, and selected the South African Astronomical Observatory (SAAO) in South Africa and a multi-institutional collaboration in Chile. The ATLAS presence augments already substantial astronomical capability in both countries.

Each of the four ATLAS telescopes can image a swath of sky 100 times larger than the full moon in a single exposure. The completion of the two final telescopes, which are located at Sutherland Observing Station in South Africa and El Sauce Observatory in Chile, enable ATLAS to observe the night sky when it is daytime in Hawai‘i.

To date, the ATLAS system has discovered more than 700 near-Earth asteroids and 66 comets, along with detection of 2019 MO and 2018 LA, two very small asteroids that actually impacted Earth. The system is specially designed to detect objects that approach very close to Earth – closer than the distance to the Moon, about 240,000 miles or 384,000 kilometers away. On January 22, ATLAS-Sutherland in South Africa discovered its first NEO, 2022 BK, a 100-meter asteroid that poses no threat to Earth.

The addition of the new observatories to the ATLAS system comes at a time when the agency’s Planetary Defense efforts are on the rise. NASA’s Double Asteroid Redirection Test (DART)—the world’s first full-scale mission to test a technology for defending Earth against potential asteroid impacts—launched November 24, 2021 on a SpaceX Falcon 9 rocket from Space Launch Complex 4 East at Vandenberg Space Force Base in California. DART will deflect a known asteroid, which is not a threat to Earth, to slightly change the asteroid’s motion in a way that can be accurately measured using ground-based telescopes.

Additionally, work on the agency’s Near-Earth Object Surveyor space telescope (NEO Surveyor) is underway after receiving authorization to move forward into Preliminary Design, known as Key Decision Point- B. Once complete, the infrared space telescope will expedite the agency’s ability to discover and characterize most of the potentially hazardous NEOs, including those that may approach Earth from the daytime sky.

“We have not yet found any significant asteroid impact threat to Earth, but we continue to search for that sizable population we know is still to be found. Our goal is to find any possible impact years to decades in advance so it can be deflected with a capability using technology we already have, like DART,” said Lindley Johnson, planetary defense officer at NASA Headquarters. “DART, NEO Surveyor, and ATLAS are all important components of NASA’s work to prepare Earth should we ever be faced with an asteroid impact threat.”

The University of Hawai‘i ATLAS is funded through a grant from the Near-Earth Object Observations Program administered by NASA’s PDCO. The Johns Hopkins Applied Physics Lab manages the DART mission for NASA’s PDCO as a project of the agency’s Planetary Missions Program Office (PMPO). NEO Surveyor is being developed by NASA’s Jet Propulsion Laboratory in Southern California and the University of Arizona and managed by NASA’s PMPO with program oversight by the PDCO. NASA established the PDCO in 2016 to manage the agency‘s ongoing efforts in Planetary Defense.

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