Curated category
Planetary science
- Solar SystemAbout 4.6 billion years ago, a dense region within a large molecular cloud collapsed under its own gravity. This event birthed the Sun and a surrounding…
- HED meteoriteHED stands for howardite, eucrite, diogenite. This acronym defines a specific clan of achondrite meteorites that make up about 5% of all falls to Earth.
- GeomorphologyGrove Karl Gilbert studied the landscapes of the Blue Gate pass in Utah with intense focus during 1875 and 1876. His notebooks from that period form an…
- PlanetIn August 2006, the International Astronomical Union voted to reclassify Pluto as a dwarf planet. This decision changed the count of planets in our Solar…
- Formation and evolution of the Solar SystemEmanuel Swedenborg, Immanuel Kant, and Pierre-Simon Laplace developed the nebular hypothesis in the 18th century. This model proposed that the Solar System…
- Magnetosphere of JupiterIn 1955, astronomers detected radio emissions from Jupiter that hinted at a powerful magnetic field. The decametric radiation extended up to 40 megahertz…
- Planetary differentiationHigh-density materials tend to sink through lighter materials. This tendency is affected by the relative structural strengths, but such strength is reduced…
- Definition of planetGreek astronomers in antiquity used the term planetes to describe star-like objects that moved across the sky over the course of a year.
- EjectaThe 22nd of July 1980 marked a violent moment at Mount St. Helens when a massive plume of pyroclastic material rose into the sky.
- Frost line (astrophysics)In 1981, astronomer Hayashi calculated that water ice could condense at a distance of 2.7 astronomical units from the Sun.
- Earth massThe symbol M Earth represents a specific quantity of matter equal to the entire planet we inhabit. Astronomers use this standard unit to compare other…