It is about 1.5 km wide. More importantly, it’s in an orbit that in the future could bring it close enough to Earth to pose a problem. Such objects are nicknamed by scientists “planet-killing asteroids”.
Three previously unknown near-Earth asteroids have been discovered by astronomers observing the twilight sky. In fact, one of them is the largest potentially dangerous asteroid discovered in years. It is about 1.5 km wide. More importantly, it’s in an orbit that in the future could bring it close enough to Earth to pose a problem. Scientists refer to these objects as planet-killing asteroids. Astronomers have discovered three Near-Earth Asteroids (NEAs) lurking in the Sun’s glare through observations made with the Dark Energy Camera made by the United States Department of Energy and located at the Cerro Tololo Inter-American Observatory. in Chile. Earth and Venus orbit an elusive population of NEAs.
A Planet Killer: Asteroid 2022 AP7
Near-Earth Asteroids (NEAs) have been found hiding in the inner solar system. This region lies between the orbits of Earth and Venus. Due to glare from the Sun, this region is notoriously difficult for asteroid hunters to observe. At dusk, astronomers were able to spot an elusive trio of NEAs by taking advantage of brief but favorable viewing conditions. One of them is a 1.5 km wide asteroid called 2022 AP7. Its orbit could one day place it in the path of the Earth. PH27 and 2021 LJ4 are two asteroids whose orbit remains completely inside that of the Earth. Astronomers and astrophysicists are particularly intrigued by 2021 PH27, as it is the closest known asteroid to the Sun.
Scott Sheppard, an astronomer in the Earth and Planets Laboratory at the Carnegie Institution for Science and lead author of a paper describing the project, said: “Our twilight survey scans the orbits of Earth and Venus for asteroids. We discovered two near-Earth objects about 1 km in diameter, which are called planet killers. Sheppard thinks there are only a few similarly sized NEAs left to discover. Most of them will have orbits that keep them inside the orbits of Earth and Venus. Due to the glare of the Sun, only about 25 asteroids have been discovered whose orbit is completely inside that of the Earth.
A colossal task
Finding asteroids in the inner solar system is a daunting task for astronomers. This area is only visible to astronomers for two brief 10-minute windows each night due to glare from the Sun. Additionally, because these observations are very close to the horizon, astronomers must observe through Earth’s atmosphere, making their observations blurry and distorted.
Thanks to DECam’s unique observation capabilities, we were able to discover these three new asteroids despite these difficulties. Astronomers can observe large areas of the sky with remarkable sensitivity using this instrument, which is one of the most sensitive wide-field CCD imagers in the world. It is characterized by a high level of performance and a wide field of vision. The term “deep observation” is used by astronomers to describe observations that capture faint objects. Being able to make both wide-field and deep-field observations is essential when searching for asteroids inside Earth’s orbit. Asteroids are faint,
Therefore, large areas of sky are needed, Sheppard explained. “DECam can cover large areas of sky at depths that are impossible to reach with smaller telescopes, allowing us to reach further, cover more sky, and probe the interior of the solar system like never before. But it’s not just about spotting asteroids that could threaten Earth. This research also contributes to understanding how small bodies are distributed in our solar system. In general, it is easier to detect asteroids that are farther from the Sun than Earth. This is why current theoretical models of asteroid populations tend to focus on these more distant asteroids. In addition, detecting these objects allows astronomers to discover how asteroids move through the inner solar system. Furthermore, they can discover how gravitational interactions and the Sun’s heat can fragment them.