Astronomers have discovered three near-Earth asteroids (NEA) lurking in the Sun’s glare thanks to twilight observations using the US Department of Energy-built Dark Energy Camera at Cerro Tololo Inter-American Observatory in Chile, a program of NSF’s NOIRLab. These NEAs are a component of a mysterious population that resides between Venus’ and Earth’s orbits. One of the largest potentially hazardous asteroid for Earth to be found in the previous eight years is one of the asteroids.
An international team has found three new near-Earth asteroids (NEAs) hiding in the inner Solar System, the region interior to the orbits of Earth and Venus, using the Dark Energy Camera (DECam) mounted on the Victor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile, a program of the NSF’s NOIRLab. The brightness of the sun makes this a notoriously difficult area for observations since asteroid hunters must deal with it.
But the astronomers managed to locate an illusive trio of NEAs by making use of the brief but advantageous observing conditions at twilight. One is the 1.5-kilometer-wide asteroid 2022 AP7, whose orbit may one day put it in the path of Earth. The orbits of the other asteroids, 2021 LJ4 and 2021 PH27, are safely kept entirely inside those of the Earth’s orbit. The fact that 2021 PH27 is the known asteroid that is closest to the Sun is of particular interest to astronomers and astrophysicists. This makes it the object in our Solar System with the largest general relativity effects, and during its orbit, its surface becomes hot enough to melt lead.
Scott S. Sheppard, an astronomer at the Earth and Planets Laboratory of the Carnegie Institution for Science and the primary author of the publication presenting this work, stated that “our twilight scan is combing the space inside the orbits of Earth and Venus for asteroids.” We have so far discovered two planet-killing-sized near-Earth asteroids that are around a kilometer across.
“There are probably just a handful more NEAs of this size left to locate,” said Sheppard. “These massive undiscovered asteroids probably have orbits that keep them mostly inside the orbits of Earth and Venus.” Because it is hard to see things close to the Sun, only about 25 asteroids with orbits that are completely inside Earth’s orbit have been found so far.
In the inner Solar System, finding hazardous asteroid is a difficult observational task. Astronomers must struggle with a brilliant backdrop sky caused by the sun’s glare and just two brief 10-minute windows each night to examine this region. Also, because these observations are made so close to the horizon, astronomers have to look through a thick layer of the Earth’s atmosphere, which can make their data hard to understand and change.
Despite these difficulties, the unique observing capabilities of DECam made it possible to find these three new asteroids. The cutting-edge device is one of the highest-performance wide-field CCD imagers in the world, enabling astronomers to capture significant portions of the sky with exceptional sensitivity. If faint objects are observed, astronomers term the observation “deep.” The ability to record both deep and wide-field data is essential while looking for asteroids inside Earth’s orbit. The US Department of Energy (DOE) provided funding for DECam, which was developed and tested at Fermilab. Sheppard explained, “Deep photos are needed because asteroids are faint and you are fighting the bright twilight sky near the Sun as well as the distorting impact of Earth’s atmosphere. Large expanses of sky are needed since inner asteroids are scarce. ” “DECam can cover enormous areas of sky to depths that are not possible with smaller telescopes, allowing us to delve deeper, cover more sky, and investigate the inner Solar System in ways never done before,” said Dr. David E. Clark.
This study is a significant step in understanding the distribution of small bodies in our solar system as well as identifying asteroids that may be dangerous to Earth. The easiest asteroids to find are those that are farther away from the Sun than Earth. As a result, these farther-off asteroids frequently dominate hazardous asteroid population theories at the moment.
Astronomers can learn more about hazardous asteroid’ movement around the inner Solar System and how gravitational forces and the Sun’s heat might cause them to fragment by finding these objects.
One of the largest and most accurate searches yet made for objects near and inside Venus’ orbit is our DECam survey, according to Sheppard. “This is a very rare chance to find out what kinds of things are hiding in the inner Solar System.”
According to Chris Davis, NSF Program Director for NOIRLab, “After 10 years of extraordinary service, DECam continues to provide vital scientific discoveries while simultaneously contributing to planetary security, a crucial service that benefits all humanity.”
The Dark Energy Survey, which was carried out by the DOE and the US National Science Foundation between 2013 and 2019, was the initial purpose for which DECam was constructed.
