9. The Asteroid Terrestrial-impact Last Alert System
(ATLAS) telescope in South Africa discovered
Comet C/2023 A3 on February 22, 2023.
Additionally, observers at Purple Mountain (Zijin
Shin or Tsuchinshan) Observatory in China found
the comet independently on images from January
9, 2023. Therefore, the comet also has the
nickname Tsuchinshan-ATLAS.
22. The small asteroid, designated C9FMVU2, was first
spotted on Thursday morning (Sept. 7), only a few
hours before it made its closest approach to Earth. At
10:25 a.m EDT (1425 GMT), the space rock passed the
planet at a distance of only 2,500 miles (4,000
kilometers) — about 1% of the Earth-moon distance.
For comparison, satellites of the U.S. navigational and
positioning constellation GPS orbit at an altitude of
12,550 miles (20,200 km).
32. For example, the Barringer
Crater in Arizona is an old
artifact from a stony
meteorite. Stony meteors like
this one are the most
abundant. We know this from
all the meteorites that we
count in the ice of Antarctica.
34. Feb. 15, a much larger meteoroid slammed
into Earth's atmosphere, and fragments of it
rained down across Texas. NASA's Johnson
Space Center confirmed the event in a
statement, which noted that the meteoroid
likely measured about 2 feet (0.6 meters)
across and weighed about 1,000 pounds (454
kilograms) when it entered the atmosphere.
