This week (January 4, 2017), NASA announced the selection of two new space missions, both to asteroids. The first mission, called Lucy, will study asteroids, known as Trojan asteroids, trapped by Jupiter’s gravity. The Psyche mission will explore a very large and rare object in the solar system’s asteroid belt that’s made of metal, and scientists believe might be the exposed core of a planet that lost its rocky outer layers from a series of violent collisions.
Lucy is targeted for launch in 2021 and Psyche in 2023. Thomas Zurbuchen, associate administrator for NASA’s Science Mission Directorate in Washington, said in a statement:
Lucy will visit a target-rich environment of Jupiter’s mysterious Trojan asteroids, while Psyche will study a unique metal asteroid that’s never been visited before. This is what Discovery Program missions are all about – boldly going to places we’ve never been to enable groundbreaking science.
The NASA announcement said:
Lucy, a robotic spacecraft, is scheduled to launch in October 2021. It’s slated to arrive at its first destination, a main belt asteroid, in 2025. From 2027 to 2033, Lucy will explore six Jupiter Trojan asteroids. These asteroids are trapped by Jupiter’s gravity in two swarms that share the planet’s orbit, one leading and one trailing Jupiter in its 12-year circuit around the sun. The Trojans are thought to be relics of a much earlier era in the history of the solar system, and may have formed far beyond Jupiter’s current orbit …
The Psyche mission will explore one of the most intriguing targets in the main asteroid belt – a giant metal asteroid, known as 16 Psyche, about three times farther away from the sun than is the Earth. This asteroid measures about 130 miles (210 km) in diameter and, unlike most other asteroids that are rocky or icy bodies, is thought to be comprised mostly of metallic iron and nickel, similar to Earth’s core. Scientists wonder whether Psyche could be an exposed core of an early planet that could have been as large as Mars, but which lost its rocky outer layers due to a number of violent collisions billions of years ago.
The mission will help scientists understand how planets and other bodies separated into their layers – including cores, mantles and crusts – early in their histories.
Bottom line: NASA has announced 2 new missions to previously unexplored asteroids. Lucy will tour 6 Trojan asteroids in Jupiter’s orbit. The other will go to 16 Psyche, a metal asteroid!
Deborah Byrd created the EarthSky radio series in 1991 and EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.