Nation: India
Objective(s): lunar orbit, lunar impact
Spacecraft: Chandrayaan-1 / MIP
Spacecraft Mass: 1,380 kg
Mission Design and Management: ISRO
Launch Vehicle: PSLV-XL (no. C11)
Launch Date and Time: 22 October 2008 / 00:52:11 UT
Launch Site: Sriharikota / SLP
Scientific Instruments:
Main Satellite:
1. terrain mapping camera (TMC)
2. hyper spectral imager (HySI)
3. lunar laser ranging instrument (LLRI)
4. high energy x-ray spectrometer (HEX)
5. Moon impact probe (MIP)
6. Chandrayaan-1 x-ray spectrometer (CIXS)
7. near infrared spectrometer (SIR-2)
8. Sub keV atom reflecting analyzer (SARA)
9. miniature synthetic aperture radar (Mini
SAR)
10. Moon mineralogy mapper (M3)
11. radiation dose monitor (RADOM)
MIP:
1. radar altimeter
2. video imaging system
3. Chandra’s altitudinal composition explorer
(mass spectrometer) (CHASE)
Results:
Chandrayaan-1, the first Indian deep space mission, was launched
to orbit the Moon and dispatch an impactor to the surface. Scientific goals included the study of the chemical,
mineralogical and “photo-geologic” mapping of the Moon.
Besides five Indian instruments, the spacecraft carried scientific equipment from the United States, the U.K.,
Germany, Sweden, and Bulgaria.
Chandrayaan-1 was launched into an initial geo-stationary transfer orbit
of 225 × 22,817 kilometers at
17.9° inclination. Over a period of 13 days,
the apogee of the orbit was increased by five burns of its 44.9 kgf Liquid Engine that successively.
Finally, the probe successfully entered lunar
orbit after a burn that began at 11:21 UT on 8 November and lasted about 13.5
minutes. Initial lunar orbital parameters were 7,502 × 504 kilometers.
Between lunar orbit insertion on 8 November
and 12 November,
Chandrayaan-1’s orbit was reduced gradually so that it
ended up finally in its operational polar
orbit at about 100 kilometers
above the lunar surface. Two days later, at 14:36 UT, Chandrayaan
released its 29-kilogram Moon
Impact Probe (MIP) which fired a small deorbit motor and went into freefall,
sending back readings from its three instruments until it crashed
onto to the lunar surface at 15:01 UT near the Shackleton crater at
the lunar south pole.
Indian scientists reported that data
from the CHASE instrument, which took
readings every 4 seconds
during its descent, suggested the existence of water in the lunar
atmosphere, although the data
remains inconclusive absent further verification. Chandrayaan-1 experienced abnormally high temperatures
beginning late November 2008, and for a time, it could only
run one scientific instrument at
a time. In May 2009, the spacecraft was delivered to a higher 200-kilometer
orbit, apparently in an attempt
to keep the temperatures aboard the satellite to tolerable levels.
Chandrayaan-1 also suffered a star sensor failure after nine months of operation in lunar orbit.
A backup sensor also failed soon
after, rendering inoperable the spacecraft’s primary attitude control
system. Instead controllers used a
mechanical gyroscope system to maintain proper attitude. Last
contact with the spacecraft was at
20:00 UT on 28 August 2009, thus falling short of its planned
two-year lifetime, although ISRO noted
that at least 95% of its mission objectives had been accomplished by then.
The most likely cause of the
end of the mission was failure of the power supply due to overheating.
Perhaps Chandrayaan-1’s
most important finding was related to the question of water on the Moon.
In September 2009,
scientists published results of data collected by the American M3 instrument which had detected absorption features on the polar regions of the surface of the Moon
usually linked to hydroxyl- and/
or water-bearing molecules. This finding was followed later,
in August 2013, by a further announce-
ment of evidence of water molecules locked in mineral grains on the
surface of the Moon, i.e.,
“magmatic water,” or water that originates from deep in the Moon’s interior.