Travel into deep space in search of strange and unusual planets that lurk beyond our solar system, known as exoplanets. Are you a junior explorer or a rocket scientist? Take our exoplanet quiz and find out how you rank!

More Info / References


1. Galaxy

Image: NASA

What is the name of our home galaxy, which includes the Sun, Earth, Mars and all of the known exoplanets?

Image: NASA
Our Milky Way galaxy contains billions of stars and planets and is, in turn, one of billions and billions of galaxies in the universe.

2. The basics

What is an exoplanet?

An exoplanet is any planet beyond our own solar system. We know that there are more planets than stars in our galaxy and so far we've found thousands of them.


Credit: NASA's Goddard Space Flight Center

How many planets found by the TESS space telescope have been confirmed?

Credit: NASA's Goddard Space Flight Center
As of March, 2019, astronomers had found more than 40 exoplanets using data from the TESS space telescope. There are more than 1,700 exoplanet candidates that await confirmation.

4. Sizes

Credit: NASA

Can you compare the size of the Hubble Space Telescope to a school bus? Or to a human scientist in Eyes on Exoplanets? (Tip: "Missions" is full of information!)

Credit: NASA
Yes! You can see Hubble compared with a school bus or a scientist. Hubble is 43.5 feet long (13.2 m) and 14 feet wide (4.2 m) at the back, where the scientific instruments are housed. Weighing about 27,000 pounds (12,246 kg), the telescope is approximately the same size and weight as a school bus. And it's much bigger than a scientist.

5. Planet types

Credit: NASA/JPL-Caltech

How many types of exoplanets can you search in Eyes on Exoplanets?

Credit: NASA/JPL-Caltech
You can search discoveries by All; Gas Giant; Neptune-like; Super-Earth and Terrestrial.

6. Super!

Credit: NASA/JPL-Caltech

There are many types of exoplanets. What is a Super-Earth and how many have been discovered?

Credit: NASA/JPL-Caltech
Super Earths are potentially rocky worlds, larger than Earth. So far, we've discovered more than 1,200 of these type of exoplanets.

7. Size

Credit: NASA, ESA and B. Holwerda (University of Louisville)

How big is our galaxy?

Credit: NASA, ESA and B. Holwerda (University of Louisville)
The Milky Way galaxy is thought to be 100,000 light-years across. Our nearest galactic neighbors are the Magellanic Clouds, which include several dwarf galaxies one-millionth the size of the Milky Way. These dwarf galaxies orbit the Milky Way, attracted by the gravity of our large spiral galaxy.

8. Missions

Credit: NASA

How many space telescopes, called missions, can you search in Eyes on Exoplanets?

Credit: NASA
Observations from the Kepler Space Telescope were used to discover most of the exoplanets we know of so far. It retired in 2018, but astronomers are still using its data to find planets. NASA launched the TESS spacecraft in 2018 and it is currently looking for even more exoplanets. You can also search for planets found by Hubble and the Spitzer Space Telescope (tip: look under Missions in the upper right and also search Observatories for ground-based telescopes).

9. Strange Worlds

Credit: NASA/JPL-Caltech

If you were to "browse planets" in Eyes on Exoplanets, which weird gas-giant exoplanet is shaped like an egg?

Credit: NASA/JPL-Caltech
The doomed planet WASP-12b orbits so close to its parent star, it's being torn apart. It takes this alien world only 1.1 Earth days to completely circle its sun. Almost two times the size of our Jupiter, WASP-12b is a sizzling gas giant whose temperature is approximately 4,000 degrees Fahrenheit (2,210 degrees Celsius). Gravity causes enormous tidal forces that are stretching the planet into the shape of an egg.