Browse Reference Articles
61 to 70 of 194 articles
-
Impact crater
An impact crater is a circular depression on a surface, usually referring to a planet, moon, asteroid, or other celestial body, caused by a collision of a smaller body (meteor) with the ... > more -
Extraterrestrial life
Extraterrestrial life is life that may exist and originate outside the planet Earth, the only place in the universe currently known by humans to support life. Its existence is currently purely ... > more -
Light-year
A light-year or lightyear (symbol: ly) is a unit of measurement of length, specifically the distance light travels in a vacuum in one year. While there is no authoritative decision on which year is ... > more -
Asteroid belt
The asteroid belt is a region of the solar system falling roughly between the planets Mars and Jupiter where the greatest concentration of asteroid orbits can be found. Despite popular imagery, the ... > more -
Eris (dwarf planet)
Eris is the largest known dwarf planet in the solar system. It is a trans-Neptunian object (TNO), orbiting the Sun in a region of space known as the scattered disc, just beyond the Kuiper belt, and ... > more -
Geosynchronous orbit
A geosynchronous orbit is a geocentric orbit that has the same orbital period as the sidereal rotation period of the Earth. It has a semi-major axis of 42,164 km (26,200 miles). In the special case ... > more -
Andromeda Galaxy
TThe Andromeda Galaxy (also known as Messier 31, M31, or NGC 224; older texts often called it the Andromeda Nebula) is a spiral galaxy approximately 2.5 million light-years away in the constellation ... > more
Search ScienceDaily
Number of stories in archives: 137,088

