General Astronomy - Uranus & Neptune

These flashcards cover key concepts related to Uranus and Neptune, including their size, density, composition, atmosphere, moons, and interior structure.

What are the sizes of Uranus and Neptune compared to Earth?

Uranus is 4.0 times the size of Earth and Neptune is 3.9 times the size of Earth.

How do the densities of Uranus and Neptune compare to Earth?

Uranus is 23% of Earth's density, and Neptune is 29.8% of Earth's density.

What is the distance of Uranus and Neptune from the Sun in AU?

Uranus is 19.2 AU and Neptune is 30 AU from the Sun.

How long is the rotation period of Uranus and Neptune?

Uranus has a rotation period of about 17 hours and Neptune about 16 hours.

What unique rotational characteristic does Uranus exhibit?

Uranus has a retrograde rotation and is tilted over 90 degrees.

What is the primary composition of Uranus?

Uranus is composed of approximately 82.5% H2, 15.2% He, and 2.3% trace amounts of water and ammonia.

What are the primary components of Neptune's atmosphere?

Neptune's atmosphere consists of about 80.0% H2, 19.0% He, and 1.5% trace amounts of water and ammonia.

How did both Uranus and Neptune get their atmospheric data?

Their atmospheric data primarily comes from Voyager 2 flybys in 1986 and 1989, along with information from ground-based observations and the Hubble and JWST telescopes.

What is notable about the rings of Uranus and Neptune?

Both planets have fairly faint sets of rings.

What characterizes the atmosphere of Uranus and Neptune compared to gas giants?

Both have zones and bands like gas giants, but they are not as clear, with a strong blue color indicating methane ice clouds.

What is the interior structure of Uranus and Neptune?

They have semi-strong magnetic fields, a churning metallic liquid inside, and multiple magnetic poles.

How many moons does Uranus and Neptune have?

Uranus has 28 small moons, while Neptune has 1 big moon (Triton) and 16 smaller ones.

What is unique about Triton's orbit?

Triton has a retrograde orbit around Neptune, suggesting it is a captured dwarf planet.

What has Voyager 2 revealed about Triton?

Voyager 2 imaged only about 40% of Triton, revealing few craters and evidence of 'maria' and fault lines possibly indicating tectonic activity.