Asteroid 2023 FW13 has just been detected by astronomers as a quasi-moon, a
space rock that orbits the sun almost simultaneously with Earth.
Asteroid that follows Earth on its annual orbit of the sun has just been
found by scientists.
The space rock, known as 2023 FW13, is a so-called "quasi-moon" or
"quasi-satellite," which means it circles the sun in a manner similar to
that of Earth but is only marginally affected by the planet's gravitational
attraction. Its diameter is reported to be 50 feet (15 meters), which is
around three huge SUVs parked side by side. 2023 FW13 travels around the sun
and Earth simultaneously, passing by our planet about 9 million miles (14
million kilometers) away. According to
NASA, the moon's diameter is 2,159 miles (3,474 km), and at its closest point
in its orbit, it is 226,000 miles (364,000 km) from Earth.
The Pan-STARRS observatory, which is perched atop Hawaii's Haleakal
volcano, made the first discovery of 2023 FW13 in March. The
Canada-France-Hawaii Telescope in Hawaii and two observatories in Arizona
later confirmed the asteroid's existence, and on April 1 the Minor Planet
Center at the International Astronomical Union, a network of scientists in
charge of naming new planets, moons, and other solar system objects,
officially listed the asteroid.
According
to some estimates, 2023 FW13 has been orbiting Earth since at least 100 B.C.
and will likely keep doing so until about the year 3700, according to
Adrien Coffinet, an astronomer and journalist who first classified the asteroid as a
quasi-moon after modeling its orbit.
Coffinet stated that it "seems to be the longest quasi-satellite of Earth
known to date."
According to Live Science sister site Space.com, after 2023 FW13 was first
discovered in March, space observers went into the data and discovered
sightings of the asteroid going all the way back to 2012.
This quasi-satellite is hanging rather close to Earth, but it's not likely
to collide with it.
The good news, according to astronomer
Alan Harris
of the Space Science Institute, is that such an orbit does not lead to an
impacting trajectory "out of the blue."
The Kamo'oalewa quasi-satellite, which was identified in 2016, is another
quasi-companion of Earth. In its orbit around the sun, the rock comes quite
close to Earth, and a research from 2021 speculated that this asteroid may
possibly be a moon piece.