Tag: science & technology

The Orion Nebula (M42) is approximately 1,344 light-years from Earth, though some measurements range from 1,300-1,500 light-years. It's one of the brightest nebulae visible to the naked eye and is the closest region of massive star formation to our solar system. Option C (1500 light-years) is the best approximation among the choices.

51 Pegasi b was discovered in 1995 by Mayor and Queloz, the first exoplanet found orbiting a main-sequence star. Supernova 1987A is a stellar explosion, Jupiter is within our solar system, and Gliese 581's planets were discovered later.

The Sun orbits the solar system barycenter due to Jupiter's gravitational pull, with a velocity of about 12 meters per second. The speed of light (option B) is far too fast, 65 mph is too slow, and the Sun is not stationary.

Mars was named after the Roman god of war (Ares in Greek mythology) due to its reddish color resembling blood. Europa and Titan are moons, not planets, while Neptune was named after the Roman god of the sea.

In 1924, during a close approach of Mars, astronomer David Todd convinced the US military to maintain radio silence to listen for potential signals from Mars - one of the earliest SETI attempts. The 1970s dates are too late for this historical event.

Mars Pathfinder (launched 1996) was a NASA probe that landed on Mars in 1997 with the Sojourner rover. Apollo was for Moon missions, Juno orbits Jupiter, and Sidewinder is a missile. The question reflects its time period.

Carbonate minerals can form and preserve fossils or biosignatures of primitive life. The Spirit rover found carbonate deposits in 2010, suggesting possible past habitable conditions. Sulfuric acid destroys fossils, while crystals and methane are not minerals that contain fossils.

Europa has a subsurface ocean beneath its ice shell and is considered one of the best candidates for primitive life. Triton orbits Neptune, Oberon orbits Uranus, and Ganymade appears to be a typo for Ganymede (though it also has an ocean).

Space-borne interferometers were designed to detect Earth-like exoplanets by combining light from multiple telescopes. X-ray and gamma-ray observatories study high-energy phenomena, while James Web should be James Webb (primarily for cosmology).

Selenites (from Selene, the Greek moon goddess) was a 19th-century term for hypothetical moon inhabitants, popularized by literature like H.G. Wells' The First Men in the Moon. The other terms are not associated with lunar creatures.