CDS (I) 2024 General Knowledge · Question 60 of 120

Correct — C, Both 1 and 2. Bhoonidhi is the National Remote Sensing Centre's open Earth-observation data hub, and Vista — short for Visualisation of Terrestrial Acquisitions — is its data-visualisation service. NRSC's own description matches statement 1: it is a full-resolution data visualisation service served through a web map interface, letting a user see the mosaic of what the satellites actually covered rather than only browse a catalogue. Statement 2 matches the same source, which records Vista as enabled for ResourceSat-2 and ResourceSat-2A, giving views in the near-infrared, red and green bands from 56 m down to 5 m resolution, together with Sentinel-2 in natural colour and Sentinel-1 synthetic-aperture radar in two polarisations in the C band.

• (a)1 only — Rejects the satellite list, but the ResourceSat and Sentinel coverage is the specific feature NRSC advertises. Vista's value is that it puts an Indian optical mission alongside European optical and radar data in one view.
• (b)2 only — Rejects the description of the service itself. Full-resolution visualisation through a web map interface is exactly what distinguishes Vista from Bhoonidhi's ordering and download pages.
• (d)Neither 1 nor 2 — Rejects both, though each is drawn from NRSC's own published description of the service.

Bhoonidhi is ISRO's single-window portal for Earth-observation data, run by the National Remote Sensing Centre at Hyderabad; it lets users search, order and download products from Indian remote-sensing satellites and from foreign missions whose data India redistributes, such as Landsat and the Sentinels. Vista is the visualisation layer on top of that archive. Instead of returning a list of scenes, it renders the acquisitions themselves as a browsable mosaic at native resolution, with day-wise and between-dates views at varying zoom so a user can see what a satellite actually covered in a pass or a cycle, and a time-lapse animation over a chosen area. The companion tool Upagrah tracks the positions of in-orbit missions in real time.

Two-statement items on a specific portal reward recognition rather than reasoning, but there is a structural clue. Statement 1 describes a service and statement 2 describes its inputs, and a made-up portal question would usually plant its error in the satellite list — for instance by naming a communications or navigation satellite that carries no imaging payload. Here every satellite named is an imaging mission, and the mix is coherent: ResourceSat carries multispectral optical sensors, Sentinel-2 is optical and Sentinel-1 is radar, which is exactly the combination a visualisation service would want because radar sees through cloud when the optical sensors cannot. Anchor Bhoonidhi to Bhuvan, ISRO's older geoportal, which UPSC has already tested — Bhuvan visualises the terrain, Bhoonidhi serves the underlying data.

• Bhoonidhi is NRSC's open Earth-observation data hub for searching, ordering and downloading satellite data products.
• Bhoonidhi Vista stands for Visualisation of Terrestrial Acquisitions and provides full-resolution data visualisation on the portal.
• Vista is enabled for ResourceSat-2 and ResourceSat-2A, Sentinel-2 in natural colour, and Sentinel-1 radar in two C-band polarisations.
• It offers day-wise and between-dates incremental views at varying zoom levels, plus a time-lapse animation over a chosen area of interest.

• Confusing Bhoonidhi with Bhuvan; Bhuvan is the visualisation geoportal of Indian terrain, Bhoonidhi is the data ordering and dissemination hub.
• Assuming an ISRO portal would carry only Indian satellites; Bhoonidhi redistributes Sentinel and Landsat data as open data too.
• Reading 'full resolution' as a claim about very high resolution imagery; it means the data are shown at their own native resolution rather than as thumbnails.

Asked as a two-statement recall item on a named ISRO service — CDS has been sampling ISRO's public data platforms steadily since the Bhuvan era.

• practice — not a real PYQ

  Which Indian organisation operates the Bhoonidhi Earth-observation data portal?

  • (a)Survey of India
  • (b)National Remote Sensing Centre
  • (c)Indian Meteorological Department
  • (d)National Atlas and Thematic Mapping Organisation

  Answer(b) National Remote Sensing Centre — the ISRO centre at Hyderabad that handles satellite data reception and dissemination.

• practice — not a real PYQ

  Sentinel-1 differs from Sentinel-2 chiefly in that Sentinel-1

  • (a)carries a synthetic-aperture radar and can image through cloud
  • (b)flies in geostationary orbit
  • (c)measures only sea-surface temperature
  • (d)carries no imaging payload

  Answer(a) carries a synthetic-aperture radar and can image through cloud — Sentinel-2 is an optical multispectral mission.