Terrestrial Planets
21% of the Earth's atmosphere is this diatomic gas.
What is oxygen?
This is the site of a very large storm on Jupiter.
What is the Great Red Spot?
Galileo lends his name to Ganymede, Io, Europa, and Callisto - the four largest moons of this planet.
What is Jupiter?
This is the name of the large landmass that existed from the late Paleozoic to the early Mesozoic era.
What is Pangaea?
Tom Hanks starred in a movie about the 13th mission of this program. Its 11th mission left NASA feeling over the moon.
What is Apollo?
Mariner 2, Mariner 5, Mariner 10, Pioneer Venus 1, Pioneer Venus 2, and an orbiter called Magellan visited this planet, whose days are longer than its years.
What is Venus?
This planet is known for rotating sideways.
What is Uranus?
Unlike Galileo, this heliocentric astronomer was actually not hated by the church.
Who is Copernicus?
This type of rock is particularly abundant along the Pacific Ocean's Ring of Fire.
What is igneous?
Months on the Islamic calendar always start on this phase of the moon, which is often depicted on flags.
What is crescent?
There are no sailors with bubble beam superpowers, but this terrestrial planet does have a day 59 times longer than Earth's, as well as poles with water-ice.
What is Mercury?
Ceres, Makemake, and Pluto are all this type of planet; the Sun is this type of star.
What is dwarf?
This astronomer developed the geocentric model of the solar system.
Who is Ptolemy?
What is Cambrian?
These are the two moons of Mars, named after Ares' twin sons.
What are Phobos and Deimos?
A sol lasts 24.6 hours, and is the defining measurement of a day on this terrestrial planet.
What is Mars?
This is the only probe that has visited all of the gas giants.
What is Voyager 2? (prompt on Voyager)
This astronomer developed the three laws of planetary motion, including that orbits are elliptical.
Who is Kepler?
Other than igneous and sedimentary, this is the third major type of rock. These rocks are created by transforming existing types of rock into new types of rock.
What is metamorphic?
This lunar phase occurs when more than half of the moon is illuminated in the night sky.
What is gibbous?
This is the only planet in the solar system that rotates clockwise, compared to the other 7 that rotate counter-clockwise.
What is Venus?
This is the organic compound that makes Uranus and Neptune blue.
What is methane?
This astronomer used the sun and shadows to come up with a shockingly accurate estimation for the circumference of the Earth.
Who is Eratosthenes?
Scientists have proposed that we are currently living in this era, named after the Greek word for "man".
What is Anthropocene?
This cluster of galaxies includes the Andromeda, the Milky Way, and the Triangular galaxies
What is the Local Group (of galaxies)?