is
His brother _ an astronomer.
are
The engineer and the astronomer _ meeting today.
is
The conference speaker _ an astronaut.
are
The astronauts _ living at the Space Station.
is
Jeff Williams, an astronomer, _ American.
are
Julie Payette and Robert Thirsk _ Canadian.
is
The flight director _ in charge of the mission.
are
Marsha Ivins and Koichi Wakata _ astronauts.
is
The discovery of water on Mars _ exciting.
are
Mars and Venus _ the closest planets to Earth.
is
Callisto _ one of Jupiter's moon.
are
Callisto and Ganymede _ two of Jupiter's moons.
is
A flag _ painted on the rocket.
are
Many flags _ painted on the rocket.
has
Mars _ a very thin atmosphere.
have
Jupiter and Saturn _ dense atmospheres.
has
Each student _ a computer.
have
All students _ computers and telescopes.
is
Tim _ going to the star party.
are
Rob's friends _ going to the star party.
has
My uncle _ always loved astronomy.
have
Most people _ never looked through a telescope.
is
Someone from the group _ missing.
are
The astronomy books _ missing from the library.
is
Earth _ denser than Saturn.
are
All the other planets _ denser than Saturn.
is
The book on astronomy _ very informative.
are
There _ many astronomy books in the library.
is
Raj _ able to work the telescope.
are
The students _ not ready for the test.
is
Your order for a solar filter _ ready for pickup.
are
Your solar filters _ ready for pickup.
is
The space station _ visible tonight.
are
The space station and the shuttle _ visible tonight.
is
Jupiter _ the largest planet in the solar system.
are
All the other planets _ smaller than Jupiter.
has
Earth _ only one moon revolving around it.
have
Jupiter and Saturn _ more than one moon.
has
The Solar System _ planets, moons, and stars.
have
Jupiter and Saturn _ many moons.
has
Saturn _ several hundred rings.
have
Jupiter, Uranus, and Neptune _ rings.
has
Our solar system _ billions of stars.
have
Many stars _ systems of planets and moons.
has
The sun _ sunspots that come and go.
have
We _ tides because of the moon's gravity.
has
Mars _ higher mountains than any other planet.
have
Most planets _ an atmosphere.
is
An asteroid _ a large rock in outer space.
are
Comets _ made of dust and ice.
is
Air _ thinner as you get further from Earth.
are
There _ eight planets in our solar system.
has
Our solar system _ one star - the sun.
have
Comets _ a wide range of orbital periods.
has
Saturn's moon, Rhea, _ oxygen in its atmosphere.
have
Comets _ an elliptical orbit.
is
Pluto _ a dwarf planet.
are
Which planets _ visible tonight?
is
Saturn _ made up of gases.
are
Earth, Mars, Venus and Mercury _ made of rock.
is
Most of the universe _ empty space.
are
Meteors _ bits of dust or rocks from space.
is
Gravity _ a force pulling matter together.
are
Comets _ like dirty snowballs of ice and dust.
is
When _ the best time to watch a meteor shower?
are
Asteroids _ often called minor planets.
has
Of the planets, Mars _ a climate most like Earth.
have
Some large asteroids _ moons.
has
Dave _ a new star atlas.
have
The astronomy club members _ a meeting tonight.
has
Dr. Li _ a degree in astronomy.
have
The astronomers _ a star party on Monday night.
is
Ely _ a member of the astronomy club.
are
Supernovas _ explosions that happen when stars die.