A global ocean lurks beneath the icy crust of Jupiter's moon Europa as seen in this artist's concept. The image shows that volcanoes may belch hot, mineral-rich plumes into the ocean, providing both the nutrients and energy for life. The volcanoes may also help crack and rearrange the crust, allowing water to escape and repave Europa's surface with fresh ice. [NASA/JPL]
One of the antennas that help track spacecraft across the solar system will take aim at one of the biggest moons in the solar system later this month. Its observations will help planetary scientists probe the moon’s structure.
Europa is one of the biggest moons of Jupiter. Jupiter itself rises just to the right of our own Moon in mid-evening, and sticks with it as they climb high across the sky later on. It looks like a brilliant star. Through binoculars, Europa and Jupiter’s three other large moons look like tiny stars quite near the planet.
Europa is considered one of the most likely homes for life in the solar system, because its icy crust probably covers a global ocean of salty water. The water, minerals, and a source of heat — from tides caused by the gravitational pull of Jupiter — provide all the basic ingredients for life.
The moon’s crust forms a rigid shell around Europa. But the tides in the water below it cause it to crack. Water may sometimes seep to the surface through these cracks before it quickly freezes, adding a glaze of fresh ice.
Observations by a large antenna at Goldstone, California, which tracks missions to the planets, will tell us more about Europa. The antenna will send out pulses of radio waves, then “listen” for their echo. The way the waves bounce back to Earth will help scientists probe the moon’s interior — shedding new light on the conditions in its hidden ocean.
Script by Damond Benningfield, Copyright 2011
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