NASA has selected its next New Frontier mission: Dragonfly, a rover-sized drone will begin coping around Titan in 2034.
Titan, Saturn's greatest moon, has long spoken far from us. An opaque atmosphere creates a freezing world where methane cycles through clouds, precipitation and rivers and lakes in the same way as the water does on earth. This environment contains all the ingredients for life ̵
Now, NASA has announced that its next New Frontier mission, led by Elizabeth "Zibi" Turtle (Johns Hopkins Applied Physics Laboratory) will let us see this exotic world as we have never done before.
A Dragonfly on the Titan
Dragonfly an eight-rotor, Curiosity-size drone, will start in 2026 for an eight-year course through the solar system before landing on Titan's sand dunes in 2034. Then, Dragonfly will perform dozens of reconnaissance flights, First, examine the methane-based grains that make up the dunes and then fly farther away to approach and enter the Selk Crater. The long-lasting impact that created this 80 km wide crater melted water ice, which blended with organic molecules. NASA's Cassini probe has already investigated this region and identified several crops where this water-organic mixture exists right on the surface – ideal sites for studying prebiotic chemistry and even seeking signs of life.
Dragonfly will land exactly one Titan year (29.5 Earth years) after the European Space Agency's Huygens probe descends through the moon's creepy atmosphere. Huygens was designed as a first look and lasted only 2½ hours with limited battery power. But the glimpse it gave us showed a world that is oddly known despite a surface temperature floating around -180 ° C (-300 ° F). From above, Huygen's river-like canals that seemed to drain into a larger sea; The landing site itself looked like a dried river or lake bed, strewn with 10 to 15 cm cobbles.
In light of this short appearance, the researchers are itching to investigate this terrain. But they will not come to rivers and lakes. Dragonfly will land as Huygens did in the northern winter as Titan's North Pole does not receive any sunlight. Even more important for communication purposes, the northern, marshy regions will not have a direct sightline to Earth. Without Cassini in orbit for relay communication, Dragonfly must transfer data directly.
Instead, Dragonfly will travel to the "Shangri-La" dune fields of Titan's equatorial region, resembling the Namib dunes in southern Africa. While Cassini's radar could investigate sea and lakes, the probe had more limited possibilities for the dunes. "The big outstanding issue is the nature of solid surface materials," Turtle explains. "They have the keys to understanding the prebiotic chemistry that is abundant on the surface of Titan."
For his studies, Dragonfly will contain many of the instruments that curiosity carries on Mars. But because the probe will fly instead of rolling, it has the ability to cover much more ground than a rover would – more than 175 kilometers (108 miles) over a 2.7 year baseline mission. It is almost twice the distance traveled to date by all Mars rover combined.
Here is a brief overview of Dragonfly's instruments:
- Downward-looking cameras examine drone's traces, while forward-looking cameras examine the horizon.
- A mass spectrometer resembles that of curiosity that will drill into the soil, liberating particles, then vacuuming it into a chamber. It will take measurements, then bake the particles and examine gases released by a gas chromatograph. A neutron-activated gamma ray spectrometer will examine the bulk surface composition. Usually, these spectrometers rely on cosmic rays to form neutrons, but Titan's atmosphere is too thick for cosmic rays to come through. Instead, this spectrometer will generate its own neutrons, send a pulse into the ground and then examine the results.
- Meteorology sensors measure wind and other atmospheric and surface conditions
- A seismograph will feel Titanquakes and use them to investigate the interior of the moon
- Other instruments?
"We make innovation, not invention," says Turtle, noting that many of these instruments already have versions on Mars surface.
Titan's distance from Earth and the subsequent time delays in communication with Dragonfly mean that the flight must be largely autonomous. The moon's atmosphere is four times closer than Earth's air, while its gravity is seven times weaker, so the flight itself is relatively easy. "If you put on wings, you would be able to fly on Titan," said NASA program researcher Curt Neibur. Similarly, self-flying drones are already common on Earth, so it's just a matter of applying the techniques to another world.
Johns Hopkins APL
] Titan's atmosphere is opaque, leaving little sunlight so Dragonfly will carry a multi-mission radioisotope thermoelectric generator (MMRTG). An MMRTG is particularly useful on Titan as it emits heat along with power. However, MMRTG produces too low a wattage for high energy activities such as flight, so it will charge a battery to power these purposes. Charging will take place during Titan's night, which lasts for eight days.
Titan's surface can be difficult; Huygens slipped a little when it landed. So Dragonfly will land on skids. It will also perform "leapfrog flights" to scout future landing sites. Its first landing site is already selected, so from there it will scout landing site B and then site C before returning to site B to land. The flights will gradually extend to approx. 8 km long.
As it flies, Titan takes pictures of the surroundings and gives the moon's resemblance to our planet, the outlook looks very much like an orange-colored earth. But there will be some differences: more obvious craters, one and another kind of geography too. "The topography of Titan is rather subdued in general compared to what we are used to on a silicate plan, only a kilometer or so high, and the dunes themselves are quite low," Turtle says.
Like Titan is easier to fly over, it's also easier to land on. Remember the "seven-minute terror" experienced by Mars explorers? On Titan, it will last for a couple of hours. The moon's low gravity means that its atmosphere is extended and the entrance begins at 1,100 km. From there, it opens its main parachute at 4 km, then discards it and opens a second at 1 km. (It needs two parachutes, because with just the main route, the descent will take even longer.) As the dragonfly can actually fly, it will disconnect its protective shell and helicopter to the landing site. You can see an animation of the landing sequence here:
Good things come to those who wait – exciting times come forward in 2034!
Want to know more about the mission? Ask all your questions next Monday: NASA hosts a "Ask me something" session on Reddit on July 1 at. 3.! EDT