White Dwarfs, Moons & Deep Space

Which type of stellar remnant is roughly Earth-sized but can have about the Sun's mass?

Correct answer: White dwarf

A white dwarf is the compact remnant left when a low- or intermediate-mass star exhausts its nuclear fuel and sheds its outer layers. It can pack roughly a Sun's mass into a volume comparable to Earth.

Further reading: science.nasa.gov ↗

Which planet is orbited by the moon Deimos?

Correct answer: Mars

Deimos is one of Mars's two small natural moons; the other is Phobos. Both are irregularly shaped and orbit much closer to Mars than Earth's Moon does to Earth.

Which moon of Jupiter is the most volcanically active body known in the Solar System?

Correct answer: Io

Jupiter's moon Io is the most volcanically active world known in the Solar System. Jupiter's gravity, together with interactions with other large moons, flexes Io's interior and generates heat that powers its volcanoes.

Further reading: science.nasa.gov ↗

What is a brown dwarf?

Correct answer: An object too low in mass for sustained hydrogen fusion

Brown dwarfs form like stars but do not have enough mass to sustain ordinary hydrogen fusion in their cores. Some can fuse deuterium for a time, so they are often described as objects between the largest planets and the lowest-mass stars.

Further reading: science.nasa.gov ↗

Which space telescope was launched in 1990 and transformed astronomy with deep-space observations?

Correct answer: Hubble Space Telescope

NASA launched the Hubble Space Telescope in 1990. Its position above most of Earth's atmosphere lets it capture sharp observations across visible, ultraviolet and near-infrared wavelengths.

Which moon is the largest satellite of Saturn?

Correct answer: Titan

Titan is Saturn's largest moon and has a dense atmosphere rich in nitrogen. It also has lakes and seas of liquid methane and ethane on its surface.

Who discovered Pluto in 1930?

Correct answer: Clyde Tombaugh

Clyde Tombaugh discovered Pluto in 1930 at Lowell Observatory in Arizona, using photographic plates to compare images of the same region of sky. Pluto is now classified as a dwarf planet under the International Astronomical Union's definition.

Further reading: lowell.edu ↗

Which international radiotelephony spelling alphabet word represents the letter J?

Correct answer: Juliet

Juliet represents the letter J in the international radiotelephony spelling alphabet, often called the NATO phonetic alphabet. Its standard code words help people distinguish letters clearly over radio and telephone connections.

Which planet has a moon named Triton?

Correct answer: Neptune

Triton is Neptune's largest moon. It travels in a retrograde orbit, opposite Neptune's rotation, suggesting it may have been captured rather than formed with the planet.

What is the closest major galaxy to the Milky Way?

Correct answer: Andromeda Galaxy

The Andromeda Galaxy is the nearest large galaxy to the Milky Way and is a spiral galaxy visible to the naked eye from a dark location. It is much farther away than the Milky Way's smaller satellite galaxies.

Further reading: science.nasa.gov ↗