MPSC 2024 Prelims Paper-I · Question 91 of 100

Correct — option (2), ESA. The European Space Agency provided the ground-station support for ISRO's Aditya-L1 solar mission, under a cooperation agreement signed between the two agencies in 2021 that also covered Chandrayaan-3. The support came from ESA's ESTRACK network: the three 35-metre deep-space antennas at New Norcia in Australia, Cebreros in Spain and Malargue in Argentina, supplemented by the 15-metre antenna at Kourou in French Guiana and the commercial 32-metre deep-space dish at Goonhilly in the United Kingdom. Their job is tracking, telemetry and command — establishing where the spacecraft is, receiving what it sends and passing commands to it — and the data they collect are routed through ESA's operations centre, ESOC at Darmstadt in Germany, to ISRO's tracking network ISTRAC for analysis. The reason ISRO needs this help is geometric rather than technical. A spacecraft a million and a half kilometres away is visible only from the hemisphere of the Earth facing it, and India's own deep-space antennas can see it for only part of each day; a mission that has to be tracked continuously through cruise, insertion and routine operations therefore needs stations spread around the globe. ESA sells exactly that service, and has done so for ISRO's earlier interplanetary missions as well. One qualification is worth adding, because it is the sort of nuance a follow-up question turns on. India is not without deep-space capacity of its own: the Indian Deep Space Network at Byalalu near Bengaluru, built for Chandrayaan-1, operates 32-metre and 18-metre antennas and received Aditya-L1's data as well. What a single site cannot provide is coverage during the hours when the spacecraft lies below its horizon, and that is what a partner network spread across three continents supplies. The support is therefore supplementary rather than a substitute.

• (1)NASA — NASA is the obvious guess and it is wrong here. The American agency operates its own Deep Space Network, with complexes at Goldstone in California, Madrid in Spain and Canberra in Australia, and it has supported Indian missions in the past — but the tracking arrangement publicised for Aditya-L1 was with the European Space Agency, under the ISRO-ESA agreement of 2021. NASA remains an important ISRO partner in other areas, most visibly the NISAR earth-observation satellite built jointly by the two agencies, and it is that general familiarity the option trades on.
• (3)JAXA — The Japan Aerospace Exploration Agency has a real and current partnership with ISRO — the Lunar Polar Exploration mission, in which JAXA is to provide the launch vehicle and rover and ISRO the lander — but it played no part in tracking Aditya-L1. JAXA's own deep-space station at Usuda supports Japanese missions. The option is offered because a candidate who knows there is an Asian partnership in Indian space cooperation may reach for it without asking which mission that partnership belongs to.
• (4)ROCOSMOS — The Russian agency — printed here as 'ROCOSMOS', though it is properly spelt Roscosmos — was not involved in tracking Aditya-L1. Russia has a long history with the Indian space programme, from the launch of Aryabhata in 1975 to the cryogenic engine cooperation of the 1990s and the human-spaceflight training arrangements for the Gaganyaan crew, and its own Luna-25 mission was in the news in the same season as Chandrayaan-3. That proximity in the news cycle is what makes the option plausible, and none of it bears on the question asked.

Aditya-L1 is India's first dedicated solar observatory. It was launched on 2 September 2023 by a PSLV from Sriharikota and placed in a halo orbit around the first Sun-Earth Lagrange point, roughly 1.5 million kilometres from the Earth in the direction of the Sun, with insertion completed on 6 January 2024. L1 is chosen because the gravitational pull of the Sun and the Earth combine there to let a spacecraft keep station with relatively little fuel, and because from that vantage the Sun can be watched continuously without eclipses or occultations. The satellite carries seven payloads, of which the Visible Emission Line Coronagraph, built by the Indian Institute of Astrophysics, is the principal instrument: it produces an artificial eclipse so that the faint corona can be studied against the overwhelming brightness of the solar disc. The scientific object is the physics of the corona, the solar wind and coronal mass ejections, which drive space weather and can disturb satellites, navigation and power grids on Earth. Operating at that distance requires ground stations distributed around the world, which is where international tracking support comes in: ESA's ESTRACK network provided it, as it had for Chandrayaan-3, and ISRO's own ISTRAC facilities received the data for analysis.

Space questions in MPSC papers usually test the mission's headline facts — launch vehicle, launch date, destination, principal instrument — but this one tests the support arrangement, which is the sort of detail that appears in the middle of a news report rather than in its headline. That is a deliberate choice: it separates candidates who followed the mission from those who read only the announcement. The lesson for preparation is to record, for every major mission, not only what it does but who helped and how. It is also worth understanding why ground-station cooperation exists at all, because the reason generalises: no single country can see a deep-space craft continuously from its own territory, so tracking is bought and sold between agencies as a routine service. Note finally that the printed option (4) reads 'ROCOSMOS'; the commission's spelling is left as set, and the agency's own name is Roscosmos.

• The European Space Agency provided ground-station support for Aditya-L1 through its ESTRACK network under an ISRO-ESA cooperation agreement signed in 2021.
• The 35-metre deep-space antennas at New Norcia (Australia), Cebreros (Spain) and Malargue (Argentina) supported the mission, with the 15-metre antenna at Kourou and the commercial 32-metre dish at Goonhilly in the United Kingdom.
• Tracking data were routed through ESA's operations centre ESOC at Darmstadt, Germany, and passed to ISRO's ISTRAC for analysis.
• Aditya-L1 was launched on 2 September 2023 by a PSLV from Sriharikota and was inserted into a halo orbit around the Sun-Earth L1 point on 6 January 2024.
• The L1 point lies about 1.5 million kilometres from the Earth towards the Sun and allows continuous observation of the Sun without eclipses.
• The mission's primary payload is the Visible Emission Line Coronagraph, built by the Indian Institute of Astrophysics, one of seven instruments aboard.
• ESA provided similar ground-station support to the Chandrayaan-3 mission.

• Assuming NASA supports every Indian deep-space mission because it is the best-known agency
• Confusing the launch of a mission with its tracking; the launch was entirely Indian, on a PSLV from Sriharikota
• Placing Aditya-L1 in orbit around the Sun or on a journey to it; it orbits the L1 point about 1.5 million kilometres from the Earth
• Mixing the agencies involved in different Indian partnerships — JAXA is the lunar polar mission partner, not a tracking provider here

Space missions are a fixed part of MPSC's science and current-affairs coverage, and questions come in three shapes: the mission's own particulars, the destination and its physics, and the partnerships around it. Aditya-L1 is likely to keep appearing because the L1 point makes a good conceptual question in its own right. Prepare each mission as a short record — vehicle, date, orbit or destination, principal payload, participating agencies — and note the printed spelling of foreign agency names, since papers reproduce them inconsistently.

No directly related past PYQ was found.

• practice — not a real PYQ

  Aditya-L1 was placed in a halo orbit around which point ?

  • (a)The Sun-Earth Lagrange point L1, about 1.5 million kilometres from the Earth
  • (b)The Earth-Moon Lagrange point L2
  • (c)A geostationary orbit 36,000 kilometres above the equator
  • (d)A polar sun-synchronous orbit about 800 kilometres above the Earth

  Answer(a) The Sun-Earth Lagrange point L1, about 1.5 million kilometres from the Earth — a halo orbit there allows the Sun to be observed continuously without eclipses or occultations, and station-keeping requires very little fuel.

• practice — not a real PYQ

  The primary payload of the Aditya-L1 mission, which creates an artificial eclipse to study the solar corona, is :

  • (a)The Solar Ultraviolet Imaging Telescope
  • (b)The Visible Emission Line Coronagraph
  • (c)The Aditya Solar wind Particle Experiment
  • (d)The High Energy L1 Orbiting X-ray Spectrometer

  Answer(b) The Visible Emission Line Coronagraph — built by the Indian Institute of Astrophysics, it blocks the bright solar disc so that the far fainter corona can be observed. The other three named instruments are also aboard, but the coronagraph is the mission's principal payload.