Satellites TeLEOS-2 and Lumelite-4 were launched in April 23 from Sriharikota by the launcher
- (1)SSLV – D2
- (2)LVM3 – M4
- (3)PSLV – C55
- (4)GSLV – F12
Answer
Why
Correct — option (3), PSLV – C55.
ISRO's mission page states: "PSLV-C55/TeLEOS-2 is launched successfully on April 22, 2023 at 14:19 hours IST from SDSC-SHAR, Sriharikota." The stem's "April 23" reads as April 2023.
It was a dedicated commercial mission through NewSpace India Limited (NSIL). TeLEOS-2, about 741 kg, was the primary satellite and Lumelite-4, about 16 kg, the co-passenger; ISRO says both belong to Singapore. So the vehicle is PSLV – C55.
ISRO's mission brochure calls it the 57th flight of PSLV and the 16th using the PSLV Core Alone (PSLV-CA) configuration.
The idea to remember: PSLV-C55, 22 April 2023, carried Singapore's TeLEOS-2 and Lumelite-4 on a commercial NSIL mission.
Why the others are wrong
- (1)SSLV – D2 — SSLV-D2, the second developmental flight of the Small Satellite Launch Vehicle, lifted off from Sriharikota on 10 February 2023.
ISRO says it was to place EOS-07, Janus-1 and AzaadiSAT-2 in a 450 km circular orbit, and reports the mission accomplished. Janus-1 belongs to ANTARIS, USA; AzaadiSAT-2 was built with about 750 girl students guided by Space Kidz India.
- (2)LVM3 – M4 — LVM3 M4 launched the Chandrayaan-3 Moon mission on 14 July 2023, according to ISRO's list of LVM3 launches.
The flight before it, LVM3 M3 on 26 March 2023, carried OneWeb satellites. Neither carried TeLEOS-2 or Lumelite-4.
- (4)GSLV – F12 — GSLV-F12 placed the NVS-01 navigation satellite, about 2,232 kg, in a geosynchronous transfer orbit on 29 May 2023, lifting off from the second launch pad at Sriharikota.
ISRO describes NVS-01 as the first of the second-generation satellites for Navigation with Indian Constellation (NavIC) services.
Concept
India's launch vehicles are named by family and flight. PSLV (Polar Satellite Launch Vehicle), GSLV (Geosynchronous Satellite Launch Vehicle), LVM3 and SSLV (Small Satellite Launch Vehicle) each number their flights; ISRO calls SSLV-D2 the second developmental flight.
PSLV-C55 had four stages, alternately solid and liquid: a solid first stage, liquid second, solid third and liquid fourth. It flew in the core-alone configuration.
After the satellites separated, the spent fourth stage stayed in orbit as POEM-2, a platform for seven non-separating experimental payloads.
RPSC's 2023 syllabus lists "Defence Technology, Space Technology and Satellites." under Science & Technology and "Major Current Events and Issues of Rajasthan, India and International Importance." under Current Affairs.
PSLV-C55 was a commercial launch for a foreign customer. TeLEOS-2, developed by Singapore's DSTA and ST Engineering, carries a Synthetic Aperture Radar for all-weather, day-and-night imaging at 1 m full-polarimetric resolution.
ISRO's list of PSLV launches shows an earlier TeLEOS-1 mission on PSLV-C29, launched on 16 December 2015.
Key facts
- PSLV-C55 launched TeLEOS-2 and Lumelite-4 on 22 April 2023 at 14:19 IST from SDSC-SHAR, Sriharikota.
- Both satellites belong to Singapore: TeLEOS-2 about 741 kg (primary), Lumelite-4 about 16 kg (co-passenger); a dedicated commercial mission through NSIL.
- Lumelite-4 is a 12U satellite demonstrating a VHF Data Exchange System for maritime e-navigation, built by A*STAR's I2R and the National University of Singapore's STAR centre.
- ISRO's mission brochure calls PSLV-C55 the 57th PSLV flight and the 16th in the PSLV-CA (core alone) configuration.
- The spent PS4 stage served as POEM-2, carrying seven non-separating experimental payloads.
Compiled from ISRO's PSLV, GSLV, LVM3 and SSLV launch lists and mission pages.
Study next
Common traps
- Same year, four vehicles: SSLV-D2, LVM3 M4, PSLV-C55 and GSLV-F12 all flew in 2023, so the payload, not the year, identifies the launcher.
- Primary and co-passenger: TeLEOS-2 (radar imaging) was the primary satellite and Lumelite-4 (a 12U communication demonstrator) the co-passenger.
- TeLEOS-1 and TeLEOS-2: the first flew on PSLV-C29 in December 2015, the second on PSLV-C55 in April 2023.
A question can name satellites and ask which launch vehicle carried them, or name a launch and ask for its date or payload.
A question can also ask which country owned a commercial payload, or the configuration and flight number of a PSLV mission.
Related PYQs
UnlockIAS will link similar questions from RAS Pre 2018 and 2016 here once those papers are published on this site.
Practice
- practice — not a real PYQ
Which ISRO launch vehicle placed the navigation satellite NVS-01 in a geosynchronous transfer orbit on 29 May 2023?
- (a)PSLV-C55
- (b)GSLV-F12
- (c)LVM3 M4
- (d)SSLV-D2
Answer(2) — ISRO's GSLV-F12/NVS-01 mission flew on 29 May 2023. Option (1) carried TeLEOS-2 and Lumelite-4, option (3) Chandrayaan-3, and option (4) EOS-07, Janus-1 and AzaadiSAT-2. - practice — not a real PYQ
The satellites TeLEOS-2 and Lumelite-4, launched by PSLV-C55 in April 2023, belong to
- (a)Singapore
- (b)Indonesia
- (c)United Arab Emirates
- (d)United States of America
Answer(1) — ISRO says both satellites belong to Singapore. Option (4) can be confused with Janus-1, which belongs to ANTARIS, USA, and flew on SSLV-D2 in February 2023. Options (2) and (3) own neither satellite.