A geostationary satellite is an earth-orbiting satellite, placed at an altitude of approximately 35,800 kilometers (22,300 miles) directly over the equator, that revolves in the same direction the earth rotates (west to east). At this altitude, one orbit takes 24 hours, the same length of time as the earth requires to rotate once on its axis. The term geostationary comes from the fact that such a satellite appears nearly stationary in the sky as seen by a ground-based observer.

Correct Option: B

A geostationary satellite is an earth-orbiting satellite, placed at an altitude of approximately 35,800 kilometers (22,300 miles) directly over the equator, that revolves in the same direction the earth rotates (west to east). At this altitude, one orbit takes 24 hours, the same length of time as the earth requires to rotate once on its axis. The term geostationary comes from the fact that such a satellite appears nearly stationary in the sky as seen by a ground-based observer.

The total annual external dose from sources in soil and cosmic rays in Mumbai, Kolkata, Chennai, Delhi and Bengaluru is 0.484, 0.81, 0.79, 0.70 and 0.825 milligray respectively. Gray is a unit for absorbed dose; when the radiation energy imparted to a kg of material is one joule, it is called a gray. Since gray is very large, milligray (one thousandth of a gray), and microgray (one millionth of a gray), are commonly used. Cosmic rays come from outer space. Their intensity at a place depends on the altitude. Cosmic rays alone contribute 0.28 milligray at the first three cities as they are at sea level; the column of air helps to reduce their intensity. At high altitudes, the protection from the column of air is less. The cosmic ray contributions are higher at 0.31 milligray and 0.44 milligray respectively at Delhi and Bengaluru as these cities are at altitudes of 216 metre and 921 metre. Air passengers receive 5 microgray per hour from cosmic rays. Parts of Kerala and Tamil Nadu are high background radiation areas (HBRA) because of the presence of large quantities of monazite in the soil. Thorium content in monazite ranges from 8-10.5 per cent. Researchers found that the radiation levels in 12 Panchayats in Karunagappally varied between 0.32 to 76 milligrays per year; the levels in 90 per cent of over 71,000 houses were more than one milligray per year.

Correct Option: A

The total annual external dose from sources in soil and cosmic rays in Mumbai, Kolkata, Chennai, Delhi and Bengaluru is 0.484, 0.81, 0.79, 0.70 and 0.825 milligray respectively. Gray is a unit for absorbed dose; when the radiation energy imparted to a kg of material is one joule, it is called a gray. Since gray is very large, milligray (one thousandth of a gray), and microgray (one millionth of a gray), are commonly used. Cosmic rays come from outer space. Their intensity at a place depends on the altitude. Cosmic rays alone contribute 0.28 milligray at the first three cities as they are at sea level; the column of air helps to reduce their intensity. At high altitudes, the protection from the column of air is less. The cosmic ray contributions are higher at 0.31 milligray and 0.44 milligray respectively at Delhi and Bengaluru as these cities are at altitudes of 216 metre and 921 metre. Air passengers receive 5 microgray per hour from cosmic rays. Parts of Kerala and Tamil Nadu are high background radiation areas (HBRA) because of the presence of large quantities of monazite in the soil. Thorium content in monazite ranges from 8-10.5 per cent. Researchers found that the radiation levels in 12 Panchayats in Karunagappally varied between 0.32 to 76 milligrays per year; the levels in 90 per cent of over 71,000 houses were more than one milligray per year.

The Master Control Facility is a facility set up by the Indian Space Research Organisation (ISRO) in the city of Hassan in the Indian state of Karnataka. Established in 1982, this facility is responsible for monitoring and controlling the satellites launched by ISRO. This was the only Master Control Facility of ISRO till another one was established in Bhopal in 2005. When ISRO wanted to a control facility, it inspected various sites that were offered to it within India. ISRO chose Hassan as the location (Location on Google Maps) because it was free of noise and encountered less terrestrial transmission than other proposed sites. Low interference was a must since the facility should be able to pick up even very weak signals from the satellite. Currently MCF controls the following 10 satellites: INSAT-2E, INSAT-3C, INSAT-3A, INSAT3E, INSAT-4A, INSAT-4B, INSAT-4CR KALPANA-1, GSAT-8 and GSAT-12. On these 10 satellites 8 are controlled from MCF Hassan and two are controlled form MCF Bhopal (INSAT-3C and INSAT-4CR.)

Correct Option: D

The Master Control Facility is a facility set up by the Indian Space Research Organisation (ISRO) in the city of Hassan in the Indian state of Karnataka. Established in 1982, this facility is responsible for monitoring and controlling the satellites launched by ISRO. This was the only Master Control Facility of ISRO till another one was established in Bhopal in 2005. When ISRO wanted to a control facility, it inspected various sites that were offered to it within India. ISRO chose Hassan as the location (Location on Google Maps) because it was free of noise and encountered less terrestrial transmission than other proposed sites. Low interference was a must since the facility should be able to pick up even very weak signals from the satellite. Currently MCF controls the following 10 satellites: INSAT-2E, INSAT-3C, INSAT-3A, INSAT3E, INSAT-4A, INSAT-4B, INSAT-4CR KALPANA-1, GSAT-8 and GSAT-12. On these 10 satellites 8 are controlled from MCF Hassan and two are controlled form MCF Bhopal (INSAT-3C and INSAT-4CR.)

MESSENGER (an acronym of MErcury Surface, Space ENvironment, GEochemistry and Ranging) is a robotic NASA spacecraft orbiting the planet Mercury, the first spacecraft ever to do so. The 485-kilogram spacecraft was launched aboard a Delta II rocket in August 2004 to study Mercury’s chemical composition, geology, and magnetic field. It became the second mission after 1975’s Mariner 10 to reach Mercury successfully when it made a flyby in January 2008, followed by a second flyby in October 2008, and a third flyby in September 2009.

Correct Option: A

MESSENGER (an acronym of MErcury Surface, Space ENvironment, GEochemistry and Ranging) is a robotic NASA spacecraft orbiting the planet Mercury, the first spacecraft ever to do so. The 485-kilogram spacecraft was launched aboard a Delta II rocket in August 2004 to study Mercury’s chemical composition, geology, and magnetic field. It became the second mission after 1975’s Mariner 10 to reach Mercury successfully when it made a flyby in January 2008, followed by a second flyby in October 2008, and a third flyby in September 2009.

The Greenhouse Gases Observing Satellite or GOSAT, also known as Ibuki (meaning breath in Japanese) is an Earth observation satellite and the world’s first satellite dedicated to greenhouse-gasmonitoring. It measures densities of carbon dioxide and methane from 56,000 locations on the Earth’s atmosphere. The GOSAT was developed by the Japan Aerospace Exploration Agency (JAXA) and launched on January 23, 2009, from the Tanegashima Space Center. Japan’s Ministry of the Environment, and National Institute for Environmental Studies (NIES) use the data to track gases causing the greenhouse effect, and share the data with NASA and other international scientific organizations. Note : On Dec. 22, 2016 China has successfully sent its first carbon dioxide monitoring satellite TanSat into space via a Long March-2D rocket. The spacecraft was launched from the Jiuquan Satellite Launch Center located in the Gobi Desert.

Correct Option: C

The Greenhouse Gases Observing Satellite or GOSAT, also known as Ibuki (meaning breath in Japanese) is an Earth observation satellite and the world’s first satellite dedicated to greenhouse-gasmonitoring. It measures densities of carbon dioxide and methane from 56,000 locations on the Earth’s atmosphere. The GOSAT was developed by the Japan Aerospace Exploration Agency (JAXA) and launched on January 23, 2009, from the Tanegashima Space Center. Japan’s Ministry of the Environment, and National Institute for Environmental Studies (NIES) use the data to track gases causing the greenhouse effect, and share the data with NASA and other international scientific organizations. Note : On Dec. 22, 2016 China has successfully sent its first carbon dioxide monitoring satellite TanSat into space via a Long March-2D rocket. The spacecraft was launched from the Jiuquan Satellite Launch Center located in the Gobi Desert.