National News


Posted January 3, 2018 4:55 p.m. EST

Scientists will study the mysteries of Saturn's largest moon or sample a moving comet for the next project in NASA's New Frontiers program, a highly competitive exploration mission that already has gone to Pluto and the Kuiper Belt, Jupiter and several asteroids for sampling.

The two proposals were announced as finalists Wednesday from a list 12. The one that's tapped to fly will become the fourth mission in the New Frontiers portfolio.

One proposal, Dragonfly, would send a drone-like craft to Saturn's moon Titan to examine the habitability of dozens of sites there. The other finalist proposed landing on a comet to take a sample that could help determine its history and origin.

The Titan and comet missions were selected as finalists "based on the outstanding and visionary science" they exhibited, said Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate, during a teleconference Wednesday.

Funding for the selected mission will be capped at $850 million.

Dragonfly would build upon observations of Titan made by the Cassini-Huygens mission, which launched in 1997 as a collaborative effort by NASA, the European Space Agency and the Italian Space Agency. It arrived at Saturn in 2004, and began making flybys of Saturn's moons, including Titan, according to NASA.

In 2005, the European Space Agency-built Huygens probe landed on Titan. The mission concluded in September, NASA's website states.

Dragonfly would land on Titan by 2034, and the mission would last several years.

"Titan is a unique ocean world ... with lakes and seas of liquid methane," said Elizabeth Turtle, the proposal's lead investigator from the Johns Hopkins University Applied Physics Laboratory in Maryland. "We're excited to continue with the mission concept."

The other proposal, Comet Astrobiology Exploration Sample Return, dubbed CAESAR, would bring back a sample from a comet previously explored by the European Space Agency, said Steve Squyres the proposal's lead investigator from Cornell University in New York.

"Comets are among the most scientifically important but among the most poorly understood," Squyres said. "They're the primitive building blocks of planets ... the source of water for the earth's oceans."

Squyres chose the so-called Comet 67P/Churyumov-Gerasimenko because so much data already has been gathered by an ESA mission known as Rosetta that flew alongside the comet before concluding last year.

CAESAR's sample, totaling about 100 grams, would return to Earth by 2038, at which point scientists around the world could study it, Squyres said.

Turtle and Squyres now will begin another year of study on their proposals, Zurbuchen said, ending with a final proposal submission in January 2019.

The proposal selected to fly will be picked in July 2019 and launched in 2025.

The three New Frontiers already underway are:

*New Horizons: Launched in 2006, the mission is the first of its kind to get a close look at Pluto and its five moons, about 3 billion miles from earth. It is expected to reach the Kuiper Belt in 2019.

*Juno: Launched in 2011, the mission set out to study Jupiter, the largest planet in our solar system. The mission will end next year.

*OSIRIS-REx: Launched in 2016, Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer is the first U.S. mission set to bring asteroid samples back to Earth. It will return to earth in 2023.