Space – MCQ – GK Questions

The Methane Sensor for Mars (MSM) aimed to measure atmospheric methane, a potential biosignature or indicator of geological activity, though results were inconclusive.

Navigation satellites in MEO (e.g., GPS at ~20,200 km altitude) have an orbital period of approximately 12 hours, ensuring global coverage with multiple overlapping orbits.

The Guiana Space Centre in Kourou is operated by CNES (France) and used primarily by ESA for Ariane and Vega launches due to its proximity to the equator, enhancing payload capacity.

Launched in 2015, AstroSat is India's first dedicated multi-wavelength space telescope, observing simultaneously in UV, optical, and X-ray bands to study celestial sources.

ChASTE (Chandra's Surface Thermophysical Experiment) measured the thermal conductivity and temperature profile of the lunar topsoil near the south pole, providing critical data for future landing missions.

Mercury has the highest orbital eccentricity (0.2056) of all major planets, meaning its distance from the Sun varies significantly between perihelion and aphelion.

Molniya orbits (inclination ~63.4°, period 12 hours) provide extended coverage over high latitudes, ideal for Russia's northern regions where geostationary satellites are ineffective.

At ~380,000 years post-Big Bang, electrons combined with protons to form neutral hydrogen, allowing photons to travel freely—this relic radiation is observed today as the CMB.

PSLV strap-on motors (PSOM) are solid-fuel boosters. Variants differ in number and size of strap-ons (e.g., PSLV-XL uses six larger PSOM-XL boosters).

Chandrayaan-3 was entirely developed and launched by the Indian Space Research Organisation (ISRO) using LVM3 rocket from Sriharikota.

Gaganyaan's Service Module uses MMH/MON3 hypergolic bipropellant engines for orbit raising, circularization, and deorbit maneuvers, ensuring reliability for crew safety.

With an axial tilt of ~98°, Uranus experiences extreme seasons where each pole gets 42 years of continuous sunlight followed by 42 years of darkness during its 84-year orbit.

Quasi-stellar radio sources (quasars) are extremely luminous active galactic nuclei where accretion onto supermassive black holes releases immense energy.

ESA's Rosetta orbited comet 67P from 2014-2016, deploying the Philae lander. It provided unprecedented data on cometary composition and activity.

NavIC operates with a network of 21 ranging and integrity monitoring stations across India for precise orbit determination and signal correction.

Main sequence stars fuse hydrogen into helium in their cores via the proton-proton chain or CNO cycle, releasing energy that counteracts gravitational collapse.

The Vikas engine, derived from France's Viking engine, uses hypergolic propellants: Unsymmetrical Dimethylhydrazine (UDMH) as fuel and Nitrogen Tetroxide (N2O4) as oxidizer.

LIGO made the first direct detection of gravitational waves (GW150914) on September 14, 2015, from merging black holes, confirming Einstein's prediction.

Edwin 'Buzz' Aldrin followed Neil Armstrong onto the lunar surface approximately 19 minutes after Armstrong during Apollo 11's EVA on July 20, 1969.

Oceansat satellites carry ocean color monitors and scatterometers for studying sea surface temperature, chlorophyll, wind vectors, and marine resources.