Astronomy & Space

NASA provides go-ahead for flying drone to discover Saturn’s moon Titan – Astronomy Now

June 28, 2019 • By
Artist’s idea of the Dragonfly mission to Saturn’s moon Titan. Credit score: NASA

NASA officers introduced that the company will transfer ahead with the event of a plutonium-powered robotic quadcopter drone to discover Saturn’s moon Titan, a hazy world lined with dunes and methane lakes that scientists say is paying homage to the traditional Earth.

The Dragonfly mission will launch in 2026 and attain Titan in 2034, descend by means of its thick ambiance and deploy a rotorcraft to make a number of hops throughout the moon’s alien floor over a 2.7-year mission, surveying dune fields and craters.

“Titan is a very Earth-like place, despite the fact that the materials are very different at this very low temperature, and the bedrock is water ice and the sand dunes are made of organic sand grains, and the liquid on the surface is liquid methane,” mentioned Elizabeth Turtle, principal investigator for the Dragonfly mission on the Johns Hopkins College Utilized Physics Laboratory.”

Most of what scientists learn about Titan got here from NASA’s Cassini spacecraft and a European Area Company probe named Huygens, which made the primary touchdown on Saturn’s largest moon in 2005.

Cassini made 127 flybys of Titan in its 13-year tour of Saturn earlier than its mission led to September 2017, unveiling the moon’s floor for the primary time to see lakes of methane with rugged shorelines, streams and sand dunes. NASA’s Voyager probes couldn’t see by means of Titan’s hazy veneer after they flew by Saturn in 1980 and 1981.

“One of the great things about Dragonfly is with the cameras it has looking forward and downward, as Dragonfly is flying over the surface, it’s going to be taking pictures and sending them back to Earth,” mentioned Curt Niebur, lead programme scientist for NASA’s line of New Frontiers missions. “So we’ll really get the expertise of flying together with Dragonfly, trying down at this alien, but very acquainted sort of floor that has these rivers and mountains.

“I think that’s going to be a tremendous experience for the public, and I think everybody’s really going to enjoy it,” Niebur mentioned.

The colourful globe of Saturn’s largest moon, Titan, passes in entrance of the planet and its rings on this true coloration snapshot from NASA’s Cassini spacecraft. Credit score: NASA/JPL-Caltech/Area Science Institute

Titan’s thick ambiance makes getting right down to the bottom tough, however as soon as there, Titan’s soupy ambiance will make for a wonderful flying setting, scientists mentioned.

“Flying on Titan is actually easier than flying on Earth,” Turtle mentioned. “The atmosphere is four times denser, at the surface, than the atmosphere at the surface of Earth, and (Titan’s) gravity is about a seventh of the gravity here on Earth. So it’s actually easier to fly on Titan. If you put on wings, you’d be able to fly on Titan.”

Cassini found climate methods on Titan, together with rain storms and winds that seem to generate waves within the methane lakes.

“You get the rain coming down, collecting into really larger lakes, the size of Earth’s Great Lakes, filled to great depth with all this liquid methane. and it really creates a kind of weather cycle, just like we have on Earth, just without the liquid water,” Niebur mentioned.

However many questions on Titan stay unanswered. It’s the Photo voltaic System’s solely moon with a dense ambiance — made primarily of nitrogen — however Titan’s orange haze hides its floor from typical cameras. Cassini peered by means of the ambiance with an imaging radar to disclose enormous land plenty, oceans and different floor options.

The temperature at Titan’s floor hovers round -184 levels Celsius (-300 levels Fahrenheit), a lot too chilly for liquid water on the floor. However there’s proof that Titan harbours an underground ocean of liquid water.

The Dragonfly drone will carry cameras, drills, seismic and climate sensors, and spectrometers to look at the composition of Titan’s rocks and soil, gathering 4 fundamental varieties of measurements. Vacuum-like suction gadgets on the craft’s touchdown skids will suck up floor materials for evaluation in an on-board miniature oven, which is able to sense any natural compounds or biosignatures within the soil.

A plutonium energy supply, often called a Multi-Mission Radioisotope Thermoelectric Generator, or MMRTG, will cost the craft’s battery to energy the devices, eight electrically-driven rotors and a high-gain antenna to beam information on to Earth.

“What really excites me about this mission is the fact that Titan has all of the key ingredients needed for life,” mentioned Thomas Zurbuchen, head of NASA’s science mission directorate. “Liquid water and liquid methane, we’ve advanced natural carbon-based molecules, and we’ve the power that we all know is required for all times.

“So we have, on Titan, an opportunity to observe the processes that were present on early Earth, when life began to form, and possibly even conditions that may harbour life today,” Zurbuchen mentioned. “We may be able to look for biosignatures there today.”

Dragonfly’s mobility will permit it to journey as much as 80 kilometres (110 miles) throughout Titan over the course of 20 or extra hops.

Concerning the dimension of a Mars rover, the flying drone will permit scientists to discover a wider vary on Titan than a mission restricted to the floor. Dragonfly will first contact down in Titan’s equatorial dune fields, then journey to a crater to analyze a area the place distant sensing observations from Cassini counsel the presence of water ice outcrops.

And in contrast to a rover on the floor, an instrumented drone is not going to be stopped or delayed by obstacles like rocks and steep slopes.

NASA chosen Dragonfly over a competing proposal named the Comet Astrobiology Exploration Pattern Return, or CAESAR, mission to develop into the fourth mission within the company’s New Frontiers programme. CAESAR would have flown a spacecraft to Comet 67P/Churyumov-Gerasimenko, the identical comet first explored by Europe’s Rosetta mission, and picked up a pattern from its nucleus for return to Earth.

The three earlier New Frontiers missions developed by NASA are all presently working in house.

The New Horizons spacecraft launched in 2006 and carried out the primary up-close flyby of Pluto in 2015, then continued farther into the outer photo voltaic system to come across a 22-mile-long (35-kilometer) world within the Kuiper Belt named Ultima Thule on 1 January this yr.

NASA’s Juno orbiter launched in 2011 and arrived at Jupiter in 2016 to review the large planet’s ambiance and magnetosphere, and the OSIRIX-Rex mission lifted off in 2016 and reached the asteroid Bennu late final yr, the place the spacecraft will retrieve a pattern for return to Earth.

Company officers introduced Dragonfly and CAESAR as finalists from an preliminary record of 12 mission proposals for the fourth New Frontiers mission in December 2017. NASA is committing as much as $850 million to design and develop the Dragonfly mission, excluding launch and operations prices.

When these bills are absolutely accounted, the mission is predicted to price round $1 billion.

Artist’s idea of the Dragonfly car at Titan. Credit score: NASA/JHUAPL

“Dragonfly will be the first drone lander with the capability to fly over 100 miles through Titan’s thick atmosphere,” mentioned NASA Administrator Jim Bridenstine. “Titan is in contrast to some other place in our Photo voltaic System, and probably the most similar to early Earth.

“This revolutionary mission would have been unthinkable just a few short years ago,” Bridenstine mentioned. “A great nation does great things. We will launch Dragonfly to explore the frontiers of human knowledge for the benefit of all humanity.”

However Dragonfly is a dangerous mission.

“This mission is bold,” Zurbuchen mentioned. “We do these bold missions that change not only what we know, but how we think what’s possible that we can do.”

Dragonfly will probably be constructed and managed at APL, which oversaw the event of the New Horizons probe and NASA’s Parker Photo voltaic Probe, which  launched final yr and has already set a file for the closest spacecraft to the Solar.

“When we got the proposal for this mission, the first proposal, the science was so compelling that we looked at all the risks that were there — and there were quite a number of them — and we just basically said we want to give them a chance,” Zurbuchen mentioned.

In a convention name with reporters Thursday, NASA officers mentioned a number of of the early dangers they recognized early with the Dragonfly idea, such because the potential for hydrocarbons to clog the probe’s science devices.

“Titan is rich in hydrocarbons,” Niebur mentioned. “Usually, when we have a NASA mission, we are struggling to find trace amounts of these things, and Titan has so many that the concern was raised that that vacuum cleaner system that sucks up the sample and deliver it to the instrument could get clogged or contaminated.”

The Dragonfly group redesigned the pattern supply system over the past year-and-a-half, throughout a preliminary “Phase A” examine funded by NASA.

“All these risks, 10 risks or so, that were there were eliminated,” Zurbuchen mentioned. “So it’s a team that has proven itself, a team that’s highly diverse in all dimensions, and therefore innovative, and brought together by a strong principal investigator.”

“One of the things about Dragonfly that is not necessarily apparent at first sight is that, while this is a new way of exploring a different planet, this is actually technology that is very mature on Earth,” Turtle mentioned. “There’s so much technology development in terms of rotorcraft here on Earth, in terms of autonomous flight, and indeed a lot of the instrumentation that we will fly on Dragonfly is based on instrumentation that is sitting on the surface of Mars right now, that has flown in space before. So really what we’re doing with Dragonfly is innovation not invention.”

Turtle’s group initially proposed launching Dragonfly in 2025, however NASA is giving the mission an additional yr to organize for launch.

“We felt at NASA … that the team could benefit greatly by some additional time to work through some of the challenges,” mentioned Lori Glaze, head of NASA’s planetary science division. “There was a very tight schedule, and we thought having a little extra time would help with that.”

The unique Dragonfly trajectory featured a flyby of Earth in 2026, one yr after its launch in 2025, adopted by additional gravity help flybys with Venus and Earth to slingshot towards Saturn, concentrating on a direct entry into Titan’s ambiance in 2034.

With a launch in 2026, engineers have deleted the primary Earth flyby from the trajectory, and Dragonfly will nonetheless attain Titan in 2034.

The spacecraft will plunge into Titan’s ambiance for a two-hour descent, utilizing friction and a parachute to decelerate earlier than the rotorcraft releases from its aeroshell and flies itself to the floor, touchdown straight on its skids.

Dragonfly’s exploration will probably be restricted to the equatorial areas of Titan, away from its methane oceans. The northern hemisphere, the place Titan’s largest seas are situated, will probably be in winter when the spacecraft arrives, with the Solar and Earth under the horizon.

“The big question that remains about the materials on the surface of Titan is the composition of the solid materials,” Turtle mentioned.

The Cassini spacecraft’s radar was in a position to resolve Titan’s methane seas and establish their chemical composition.

“The big outstanding question is what the nature of these solid surface materials are, and that’s where the keys to understanding the prebiotic chemistry that is so abundant on Titan lies, in the solid surface materials,” Turtle mentioned.

E mail the creator.

Observe Stephen Clark on Twitter: @StephenClark1.