Why this matters now
Chandrayaan-2 is tested for: launch 22 Jul 2019 GSLV Mk III-M1 (LVM3) SHAR Second Launch Pad — first interplanetary use of LVM3; Chair K. Sivan; three modules: Orbiter + Vikram Lander + Pragyan Rover; mass 3850 kg; lunar orbit insertion 20 Aug 2019; Vikram crash 7 Sept 2019 02:00 IST at ~2.1 km altitude due to thrusters firing more than intended (Failure Analysis Committee report); orbiter operational with 8 instruments incl. IIRS, CLASS, OHRC (highest-res ~25 cm map of Moon to date); ISRO declared 98% mission success (orbiter-driven).
Three modules
| Module | Mass | Outcome |
|---|---|---|
| Orbiter | 2379 kg | Healthy, 7-year mission life; 8 instruments. |
| Vikram Lander | 1471 kg | Crashed 7 Sept 2019. |
| Pragyan Rover | 27 kg | Lost with lander. |
Orbiter instruments: TMC-2 (5 m), OHRC Orbiter High Resolution Camera 25 cm (best lunar imagery), IIRS Imaging Infrared Spectrometer (water/hydroxyl), CLASS X-ray spectrometer, SOLEXS solar X-ray, ChaCE-2 Chandra’s Atmospheric Composition Explorer, DFSAR Dual-frequency SAR L+S band, XSM.
Why Vikram crashed
Failure Analysis Committee report (ISRO): the five braking thrusters fired at higher thrust + longer duration than intended — software/algorithm under-anticipated bias. The lander began deviating from its descent path at the rough braking phase; software lacked sufficient margin in the fine braking phase to correct. Lander hit lunar surface within 500 m of target at ~2.1 km altitude (~60 km/s residual velocity reported but disputed).
Lessons applied to Chandrayaan-3: larger fuel margin; expanded landing zone 4 km × 2.5 km vs 500 m × 500 m; stronger legs; more sensors; modular software; throttleable engines tuned.
Orbiter science results
- OHRC: highest-resolution lunar imagery ever (~25 cm/pixel).
- IIRS: confirmed presence of hydroxyl (OH) + molecular water (H2O) signatures across the lunar surface (Aug 2021 publication).
- CLASS: detected sodium emission from sunlit Moon surface (2022 publication).
- Mapped minor element distributions.
- Orbiter relayed comms during Chandrayaan-3 landing (Aug 2023).
UPSC angle
Know CHANDRAYAAN-2 — LAUNCH 22 JULY 2019 GSLV Mk III-M1 (LVM3) Second Launch Pad SHAR — first interplanetary use of LVM3; Chair K. SIVAN; THREE MODULES Orbiter (2379 kg) + Vikram Lander (1471 kg) + Pragyan Rover (27 kg) total 3850 kg; lunar orbit insertion 20 Aug 2019; ORBITER 100 km polar lunar orbit 7-year life 8 instruments TMC-2 + OHRC 25 cm BEST LUNAR IMAGERY + IIRS + CLASS + SOLEXS + ChaCE-2 + DFSAR L+S band + XSM; VIKRAM CRASHED 7 SEPT 2019 02:00 IST at ~2.1 km altitude FIVE BRAKING THRUSTERS FIRED HIGHER THRUST + LONGER DURATION THAN INTENDED — software algorithm under-anticipated bias; lander deviated rough braking phase software lacked margin fine braking; hit within 500 m of target; ISRO declared 98% MISSION SUCCESS orbiter-driven; orbiter relayed comms for Chandrayaan-3 landing Aug 2023; IIRS Aug 2021 confirmed OH + H2O across lunar surface; CLASS 2022 detected sodium emission from sunlit Moon; lessons applied to Chandrayaan-3 larger fuel margin + expanded landing zone 4x2.5 km vs 500x500 m + stronger legs + more sensors + modular software + throttleable engines tuned.
Frequently asked questions
When was Chandrayaan-2 launched?
22 July 2019 by GSLV Mk III-M1 from Second Launch Pad SHAR — the first interplanetary use of India’s heavy-lift launcher.
What happened to the Vikram lander?
Crashed 7 September 2019. The five braking thrusters fired at higher thrust + longer duration than intended; lander deviated from descent path + hit lunar surface ~2.1 km from target. Failure analysis committee identified software/algorithm bias.
Is the Chandrayaan-2 orbiter still working?
Yes — healthy in 100 km polar lunar orbit. Carries OHRC (25 cm/pixel imagery), IIRS (water mapping), CLASS, DFSAR. Relayed comms during Chandrayaan-3 landing Aug 2023.
What was the mission success rate?
ISRO declared 98% success based on orbiter functionality + science objectives. Lander/rover (2%) failed.