OrbitalHub

NASA dixit:

“March 31, 2005. NASA’s Cassini spacecraft successfully flew by Saturn’s largest moon, Titan, at about 2,400 kilometers (1,500 miles) above the surface.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. And those six months are the thrilling final chapter in a historic 20-year journey.”

Image credit: NASA

NASA dixit:

“January 14, 2005. This is an artist’s interpretation of the area surrounding the Huygens landing site, based on images and data returned.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. (And those six months are the thrilling final chapter in a historic 20-year journey.)”

Image credit: NASA

NASA dixit:

“January 14, 2005. Image collected during the 147-minute plunge through Titan’s thick orange-brown atmosphere to a soft sandy riverbed by the European Space Agency’s Huygens Descent Imager/Spectral Radiometer. In 4 minutes and 40 seconds, the movie shows what the probe ‘saw’ within the few hours of the descent and the landing. On approach, Titan appeared as just a little disk in the sky among the stars, but after landing, the probe’s camera resolved little grains of sand millions of times smaller than Titan.

At first, the Huygens camera just saw fog over the distant surface. The fog started to clear only at about 60 kilometers (37 miles) altitude, making it possible to resolve surface features as large as 100 meters (328 feet). Only after landing could the probe’s camera resolve the little grains of sand. The movie provides a glimpse of such a huge change of scale.”

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. (And those six months are the thrilling final chapter in a historic 20-year journey.)”

Image credit: NASA

NASA dixit:

“On January 14, 2005, ESA’s Huygens probe made its descent to the surface of Saturn’s hazy moon, Titan. Carried to Saturn by NASA’s Cassini spacecraft, Huygens made the most distant landing ever on another world, and the only landing on a body in the outer solar system. This video uses actual images taken by the probe during its two-and-a-half hour fall under its parachutes.

Huygens was a signature achievement of the international Cassini-Huygens mission, which will conclude on September 15, 2017, when Cassini plunges into Saturn’s atmosphere.”

Video credit: NASA Jet Propulsion Laboratory

NASA dixit:

“After almost 20 years in space, NASA’s Cassini spacecraft begins the final chapter of its remarkable story of exploration: its Grand Finale. Between April and September 2017, Cassini will undertake a daring set of orbits that is, in many ways, like a whole new mission. Following a final close flyby of Saturn’s moon Titan, Cassini will leap over the planet’s icy rings and begin a series of 22 weekly dives between the planet and the rings.

No other mission has ever explored this unique region. What we learn from these final orbits will help to improve our understanding of how giant planets – and planetary systems everywhere – form and evolve.

On the final orbit, Cassini will plunge into Saturn’s atmosphere, sending back new and unique science to the very end. After losing contact with Earth, the spacecraft will burn up like a meteor, becoming part of the planet itself.

Cassini’s Grand Finale is about so much more than the spacecraft’s final dive into Saturn. That dramatic event is the capstone of six months of daring exploration and scientific discovery. (And those six months are the thrilling final chapter in a historic 20-year journey.)

At times, the spacecraft will skirt the very inner edge of the rings; at other times, it will skim the outer edges of the atmosphere. While the mission team is confident the risks are well understood, there could still be surprises. It’s the kind of bold adventure that could only be undertaken at the end of the mission.

Cassini’s final images will have been sent to Earth several hours before its final plunge, but even as the spacecraft makes its fateful dive into the planet’s atmosphere, it will be sending home new data in real time. Key measurements will come from its mass spectrometer, which will sample Saturn’s atmosphere, telling us about its composition until contact is lost.

While it’s always sad when a mission comes to an end, Cassini’s finale plunge is a truly spectacular end for one of the most scientifically rich voyages yet undertaken in our solar system. From its launch in 1997 to the unique Grand Finale science of 2017, the Cassini-Huygens mission has racked up a remarkable list of achievements. “

Video credit: NASA Jet Propulsion Laboratory

Credits: Mark Dowman

Airships are making a big comeback now as the energy consumption for all modes of transportation is being re-analyzed. Missions with special requirements like surveillance and reconnaissance missions and transportation of heavy payloads to remote outposts are the main driver for the reinvention of the airship.

But Earth is not the only place where airships can be deployed. There are a number of destinations in the solar system that would make a perfect environment for deployment and operation of airships, like Mars, Venus, and Titan – Saturn’s largest moon.

The presence of an atmosphere makes possible the use of vehicles that can fly within atmosphere for planetary exploration. Also, planetary exploration with low-powered vehicles like airships really makes sense considering the fact that energy is always at a premium.

So far, the only extraterrestrial deployment of an airship was performed during the Vega mission to Venus, in 1984. Two balloons were released and they floated 54 km above the planet’s surface for nearly two days.

Lighter-Than-Air (LTA) AERial ROBOTS (AEROBOTS) would present some advantages over their Heavier-Than-Air (HTA) siblings and the traditional planetary scouts, the exploration rovers: they would have long-duration mission and long-distance capabilities, they would not have to deal with obstacle avoidance problems, and they have low-power consumption. However, the environment in which the airship will operate will impose some restrictions on the capabilities of the airship (consider things like atmospheric composition and density, temperature, and the amount of solar radiation available). More on the planetary environments in the solar system and airship evaluations for each one of them can be found here.

NASA has funded a number of projects for solar system exploration that make use of aerobots. The Jet Propulsion Laboratory’s Planetary Aerobot Program is developing balloons to support scientific payloads in the atmosphere of other planets in our solar system. You can find more details about JPL’s Planetary Aerobot Program here.