CH 7 Quiz Astronomy (Last test)

The smaller objects in the solar system composed mainly of ices (frozen gases) that usually orbit far from the Sun are called:

comets

What is one way that astronomers have actually gotten an idea of the age of the surfaces of terrestrial planets other than the Earth?

counting craters

In radioactive dating, the measure scientists use to note how long (on average) a particular radioactive nucleus will take to decay is called its

half-life

During the process of differentiation,

heavier materials sink to the centers of molten planets

The inner planets are made mostly of rock and metal bc

it was so hot where the inner planets formed that the lighter materials evaporated

The planet closest to the Sun in the solar system is:

mercury

The first trans-Neptunian objects astronomers found (in 1930) is called

Pluto

Which of the following places is most likely NOT to be differentiated?

a small asteroid

Radioactive dating techniques have revealed that our Earth and moon are approximately how old?

about 4.5 billion years

Generally, planets and moons in our solar system are named after

gods and goddesses from mythology

If you were to take a large sample of the four giant planets, the most common element you would find in them is:

hydrogen

In general, the further the planets are from the Sun, the cooler they are. What other factor can have a significant influence on a planet's surface temperature?

its atmosphere (whether it has one and how thick it is)

Which of the following is NOT a terrestrial planet?

jupiter

The rate at which a collection of the same radioactive atoms will decay depends on

only on internal processes within the atoms; nothing external matters

Today, the chemistry of the terrestrial planets does not include a lot of free hydrogen. Chemists call the chemistry in the places like the Earth

oxidized

The material that would eventually make all the major bodies in our solar system first gathered together as smaller pcs which astronomers call

planetesimals

In the far future, a visiting tourist from another planetary system asks to see the most massive object in our solar system. Where would you take him/her/it?

the sun

Which of the following characteristics do all four terrestrial planets have in common?

they all have solid surfaces with signs of geological activity on them