In 1995 51 Pegasi B was the first exoplanet to be discovered orbiting a sun like star. “Our analysis … KOI-456.04 is an important find because it and its host star mirror our solar system. Earth is the only planet in the solar system where life is known to exist and where we live.

The program's primary goals, as described in the 2014 NASA Science Plan, are to discover planets around other stars, to characterize their properties and to identify planets that could harbor life. Exoplanets—worlds outside our solar system—are everywhere.

All of the planets in our solar system orbit around the Sun. Exoplanet Exploration Program NASA's science, technology and mission management office for the exploration of exoplanets. And some stars have none.

So, astronomers use other ways to detect and study these distant planets. However, there are thousands of other "candidate" exoplanet detections that require further observations in order to say for sure whether or not the exoplanet is real. Exoplanet Forecast: Hot and Wet This artist's concept shows "The Behemoth," an enormous comet-like cloud of hydrogen bleeding off of a warm, Neptune-sized planet just 30 light-years from Earth.

This plot of data from NASA's Spitzer Space Telescope tells astronomers that a toasty gas exoplanet, or a planet beyond our solar system, contains water vapor.

In fact, there are a whole lot of them: Scientists have found over 4,000 exoplanets, and think that most stars have their own solar systems. This graphic shows a comparison of discovered exoplanets with our own solar system. Some stars have many planets, and some have none. But, on average, astronomers think there is one planet for every star in our galaxy. Water covers 2/3 of the Earth’s surface. That’s just how many we’ve found so far. Hubble works alongside other telescopes to satisfy our curiosity about worlds beyond our solar system. As we all know that our planet has one satellite (Moon). Exoplanets are very hard to see directly with telescopes.

It is less than twice the size of Earth and receives a similar amount and type of light from its sun-like star.

Within 10 parsecs (32.6 light-years), there are 97 exoplanets listed as confirmed by the NASA Exoplanet Archive.

This distant solar system circles the star Kepler-160, a G dwarf star like our Sun located about 3,000 light years from Earth. There are different types of exoplanets just like the different planets in our solar system. As of 2019, there have been 4,044 confirmed discoveries of exoplanets. Planets that orbit around other stars are called exoplanets. They are hidden by the bright glare of the stars they orbit. There are eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.

That makes a total of four planets. We now know that worlds beyond our solar system—known as exoplanets—do exist. Earth is the densest planet in the solar system.