Jupiter to the Rescue

A discovery reveals Jupiter may be acting as a magnet for asteroids that are heading towards Earth

Sep 12, 2012 | By Cameron Keady
NASA

Have no fear, Earthlings. Jupiter is here to protect our little planet. In the early hours of September 10, an astronomer in Oregon spotted a bright flash of light on Jupiter. Astronomers believe this brilliant burst to be an asteroid hitting the giant planet. Scientists say that the asteroid may have been heading for Earth, but instead, Jupiter took the blow. And this may not be the first time Jupiter has saved Earth from a near collision.

Stellar Strength

Jupiter has the strongest gravitational pull of any planet. It is close to the asteroid belt—a region of irregular shaped rocks hurtling through space between Mars and Jupiter. These pieces of space matter are made mainly of rock and metal, leftover scraps from when the solar system formed.

Jupiter's gravitational field pulls in comets and asteroids before they come close to Earth.
NASA
Jupiter's gravitational field pulls in comets and asteroids before they come close to Earth.

The gravitational pull of Jupiter grabs passing asteroids and comets and pulls them to its surface—and away from Earth. The impacts are leading scientists to study possible scars from asteroids on Jupiter. Chances of actually hitting Earth are very unlikely, but scientists keep a close watch on asteroids as there are so many of them in orbit.

The Gas Giant

Jupiter is the most massive planet in the solar system. It is composed mostly of two elements: hydrogen and helium. This has given Jupiter the nickname “gas giant,” because, unlike Earth, it has little rock or solid matter in its make-up. The name fits, as Jupiter is larger than all the other planets combined and can give off more energy than the sun.

Surrounding Jupiter are more than 60 moons, the most of any planet in our solar system. The four brightest are called the Galilean satellites. They are named after the Italian mathematician Galileo, who discovered the moons in 1610. Ganymede is the largest of the four. It is larger than Mercury and one-third the size of Earth. Io is another one of the Galilean Satellites. It has more than 400 active volcanoes.

Currently, a U.S. space probe named Juno is headed to Jupiter and its moons. Juno was launched on August 5, 2011, and is scheduled to arrive in July 2016. The probe will orbit Jupiter every 11 days to study the gas giant’s atmosphere, auroras, and gravitational field. The information it sends back will help reveal the history of our solar system’s largest planet and Earth’s possible protector!