India's solar mission Aditya-L1 has been placed in a halo orbit around which point?
- A.The second Lagrange point, L2
- B.The first Lagrange point, L1
- C.A polar orbit around the sun
- D.A geostationary orbit around the earth
Correct answer
Explanation
The correct answer is B, the first Lagrange point, L1, of the sun and earth system, about 1.5 million kilometres from the earth towards the sun. A Lagrange point is a place where the gravitational pulls of the two bodies and the orbital motion balance, so a spacecraft can stay there with very little fuel, and from L1 the sun can be watched continuously without eclipse or occultation. Aditya-L1 was launched on 2 September 2023 by a PSLV.
Option A, L2, lies on the far side of the earth from the sun and is used by telescopes that look away from the sun. Option C is wrong because the spacecraft orbits a point in the sun-earth system, not the sun itself. Option D would put it in earth orbit, where the earth would block the view for part of every day, which is precisely what the mission had to avoid. Remember the pair: L1 for solar watching, 1.5 million km.
Read the full article: Indian Satellites and NavIC: Series, Firsts and MCQs
Practice Questions
View allWhich was India's first satellite and in which year was it launched?
- A.Rohini, 1980
- B.Aryabhata, 1975
- C.Bhaskara-1, 1979
- D.APPLE, 1981
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It was launched on 19 April 1975 by a Soviet launch vehicle, since India had no vehicle of its own at the time, and it carried experiments in X-ray astronomy, solar physics and the ionosphere.
Read the full explanation →What does NavIC stand for?
- A.Navigation with Indian Constellation
- B.National Voyage and Indian Communication
- C.Navigation Indian Coordinates
- D.Navigational Information Centre
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The name was given in 2016 to the Indian Regional Navigation Satellite System, IRNSS, when the seventh satellite of the constellation was placed in orbit, and the word navik also carries the sense of a sailor or navigator, which is why it was chosen.
Read the full explanation →The NavIC constellation was designed with how many satellites?
- A.Four
- B.Seven
- C.Nine
- D.Twenty-four
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The system was designed as a constellation of seven satellites, three of them in geostationary orbit and four in geosynchronous orbits inclined to the equatorial plane, a small number being enough because the service area is regional and not global.
Read the full explanation →Which was India's first satellite dedicated exclusively to meteorology?
- A.INSAT-1B
- B.Kalpana-1
- C.Bhaskara-2
- D.Oceansat-1
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Launched in 2002 as METSAT, it was the first Indian satellite built only for weather work, and it was renamed Kalpana-1 in memory of Kalpana Chawla, the India-born astronaut who died in the Columbia accident of 2003.
Read the full explanation →Astrosat, launched in September 2015, was India's first satellite of which kind?
- A.Radar imaging satellite
- B.Dedicated multi-wavelength space observatory
- C.Navigation satellite
- D.Educational satellite
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Astrosat was launched on 28 September 2015 by a PSLV and carries instruments that observe the same cosmic source in the ultraviolet, the visible and the X-ray bands at the same time, which is what multi-wavelength means and what makes the mission unusual among space telescopes of its size.
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