Is there a tenth planet in our solar system?
No. On August 23, 2006, the International Astronomical Union decided that the solar system contains only eight planets. Pluto, which […]
No. On August 23, 2006, the International Astronomical Union decided that the solar system contains only eight planets. Pluto, which […]
Alignments of the fast-moving inner planets can occur as regularly as every few months or so, while groupings of the
Earth’s circumference was first accurately measured more than 2,000 years ago by the Greek astronomer Eratosthenes, who at the time
The famous Northern and Southern Lights — Aurora Borealis and Aurora Australis for those Latin lovers among us — are
While no direct link between sunspots and Earthly events, such as volatile stock markets, has ever been found, extremes in
Most estimates place the number of stars in our galaxy at between 100 billion and 500 billion.
The Milky Way’s disk spans at least 100,000 light-years and probably contains several hundred billion stars, which makes our home
Quite a few. Most estimates place the number of galaxies at around 100 billion. Most of those galaxies are little
The largest visible-light telescope currently in operation is at Gran Canarias Observatory, and features a 10.4-meter (34-foot) primary mirror. The
The true inventor of the first telescope is somewhat difficult to nail down. However, the first person to apply for