Beyond our solar system


People don’t have to go to a place to explore it. Many of Earth’s spacecraft are sending back images, data, and other information for scientists to study. Here’s a look at what we’re discovering.

Speeding Stars

One exciting mission is called Gaia. It’s measuring the distances and motions of more than a billion stars in our galaxy, the Milky Way. In 2018, scientists released new data from Gaia that led to many discoveries.

For example, astronomers discovered two small stars that speed through space at 8 million kilometers (5 million miles) per hour. These stars are so fast, they will eventually escape the Milky Way.

Scientists think each star was once whirling around another small star. When that star blew up, the surviving stars kept going at the same high speed.

This illustration shows the movement of stars, as tracked by Gaia.

Technicians ready TESS for launch.

Seeking New Earths

In 2018, NASA launched a spacecraft to find new planets going around stars other than our sun. This spacecraft is named TESS for Transiting Exoplanet Survey Satellite. If a planet passes in front of its star, the star’s light dims a little. That lets TESS discover the planet.

TESS found its first planet going around a star named Pi Mensae. This star is like the sun. But the planet is much closer to the star than Earth is to the sun. So, the planet must be too hot to live on. Over time, TESS will probably discover thousands of new planets. Maybe some will be more like Earth.


TESS launches.­­

Looking Beyond

Meanwhile, an old telescope is still showing us new things in space. This is the Hubble Space Telescope, which NASA launched in 1990. Hubble looks at planets, stars, and other galaxies.

Hubble has had great success because it’s above Earth’s atmosphere. Air shakes the beam of light from a star, making the star twinkle. Yes, a twinkling star is beautiful. But, the twinkle makes it harder to study the star’s light. Out in space, stars don’t twinkle, so Hubble sees them more clearly.

What’s Next?

Hubble is fairly small. Its main mirror is only about 2.4 meters (8 feet) across. NASA wants to launch a much bigger telescope. This one is called the James Webb Space Telescope. It’s nearly three times bigger than Hubble. And like Hubble, this telescope will be above Earth’s atmosphere and will see planets, stars, and galaxies clearly. Who knows what we will see next in space?

the James Webb Space Telescope