Space (Physics) Part-III

Phoenix was a robotic spacecraft on a space exploration mission on Mars under the NASA's Mars Scout Program. The Phoenix lander descended on Mars on 25 May, 2008.

Spirit, also known as MER-A (Mars Exploration Rover -A), is a robotic rover on Mars active from 2004 to 2010. It was one of twin rovers of NASA's Mars Exploration Rover Mission. It landed successfully on Mars on January 4, 2004.

The second rover, Opportunity (MER-B) landed on the other side of the planet. Robotic rover Curiosity was launched on November 26, 2011 under the NASA's Mars Science Laboratory mission while Perseverance rover was launched on July 30, 2020 as part of NASA's Mars 2020 mission.

NASA's Spirit and Opportunity mission on Mars have found the evidence of sulfate which clearly indicated the presence of water in past. Gypsum which is a type of sulfate also found on Mars. But the presence of Methane on Mars has raised the possibility of life on the planet.

As per report released by U.S. Journal 'SCIENCE' in July, 2018, astronomers have found a massive underground lake on Mars. It is estimated that this lake is 20 km across and 1.5 km beneath the planet's southern polar ice cap.

The first evidence of methane in the atmosphere of Mars was measured by ESA's Mars Express Orbiter. NASA's Curiosity rover also detected methane presence in the atmosphere of Mars.

Jupiter's atmosphere contains mainly Helium and Hydrogen with a trace amount of Water, Ammonia, Methane and other Carbon compounds.

Saturn is the sixth planet from the Sun and the second-largest planet in our Solar System. Saturn contains approximately 75% hydrogen and 25% helium with traces of other substances like methane, ammonia, water ice etc. Hence, among the given options, option (d) is the most appropriate answer.

Saturn has the least density among all planets of our Solar system.

The Space Shuttle is a reusable spacecraft that takes off like rocket, orbits the earth like a satellite and then lands like a glider. The space shuttle was made up of three main parts. The orbiter, the external tank and the solid rocket booster.

These shuttles are fuelled with liquid hydrogen and liquid oxygen. Challenger, Columbia, Discovery, Atlantis and Endeavour are the space shuttles of NASA, but all of these are retired.

Apollo-8 was the first mission to take humans to the moon and back. It was launched from Cape Kennedy, Florida, the United States on December 21, 1968.

Selene-1 is Japan's first lunar orbiter, which was launched on September 14, 2007. The orbiter's nickname Kaguya was selected by the general public.