Chandrayaan-1 is a satellite of the Indian Space Research Agency (ISRO) whose mission was developed in polar orbit around the Moon.

This mission had the cooperation of the European Space Agency and NASA.

The project was initially planned for an approximate duration of 2 years, with a spacecraft in polar orbit, about 100 km above the lunar surface.

There is special interest in the study of the polar regions, because it is suspected that they may contain water in the form of ice.

Chandrayaan-1 spacecraft checks prior to launch. Credit: Indian Space Research Organization.

Chandrayaan-1 equipment

Chandrayaan-1 was equipped with instruments to image the Moon in the visible spectrum, near infrared and X-rays.

The spacecraft weighed 1,304 kg and carried equipment designed to impact the Moon and analyze the gases produced by the collision.

Chandrayaan-1 carried twelve scientific instruments: seven came from laboratories in India; and five were of international manufacture.

  • Sub-keV Atom Reflecting Analyzer (SARA), of European origin. With it the surface composition of the Moon was studied.
  • Moon Mineralogy Mapper (M3), of American origin, A spectrometer for analyzing minerals on the lunar surface.
  • S-Band MiniSAR: to detect possible ice on the Moon’s polar caps.
  • Near Infrared Spectrometer (SIR-2), of European origin. To inspect minerals on the lunar surface, using infrared frequencies.
  • Radiation Dose Monitor (RDM), of Bulgarian origin. Its mission was to measure environmental radiation on the Moon.
  • Terrain Mapping Camera (TCM): to obtain panchromatic photographs with a resolution of approximately five meters.
  • Lunar Laser Ranging Instrument (LLRI): Using a laser, this instrument had to determine the topography of the surface.
  • Energy X-ray spectrometer (LEX): to detect the presence of certain minerals such as silicon, aluminum, magnesium, carbon or iron.
  • Hyper Spectral Imager (HySI): to produce a mineralogical map in the bands between four and six hundred nanometers.
  • Moon Impact Probe (MIP): the impactor carried by the satellite to collide with the surface of the Moon and thus study the components of the ejected material.

Launch of the Chandrayaan-1

The Indian launcher PSLV-C11, which carried the probe, took off on October 21, 2008, from the Satish Dhawan Space Center, Sriharikota.

Indian rocket launch. Credit: Reuters.

Arrival of the probe to the Moon

On November 8, 2008, Chandrayaan-1 went into lunar orbit. It was a historic triumph for Indian astronomy.

Six days later, on November 14, 2008, the probe dropped the lunar impact module from a height of 100 kilometers.

Lunar crater as seen by the Chandrayaan-1 Mineralogy Mapping team. Credit: Wikipedia.

For 312 days, Chandrayaan-1 studied the lunar surface and produced a complete map of the lunar topography in three dimensions, as well as its chemical characteristics.

Among other achievements, Chandrayaan-1 detected wet soil on the surface of the Moon, confirming the existence of water on our satellite.

Last days of the Chandrayaan-1 mission

In early 2009, one of the probe’s sensors was burned out by solar radiation.

Technicians raised the orbit of Chandrayaan-1 from 100 km to 200 km above the lunar surface.

On August 28, 2009, contact with the probe was lost. Chandrayaan-1 had operated for 312 days in lunar orbit, making 3,400 orbits and covering 95% of its targets.

The Chandrayaan-2 mission

India continued with attempts to reach the Moon. Ten years later, on July 22, 2019, the Chandrayaan-2 spacecraft was launched into space to complete the lunar mission.

The spacecraft included a lunar orbiter, a lander, and a rover.

The lunar landing module was named Vikram, after the scientist Vikram Sarabhai, father of the Indian space program.

Chandrayaan-2 successfully passed the Moon approach and braking phase upon reaching the chosen landing site.

Vikram broke away from the orbital module and had to fine-tune his speed to land smoothly on the surface of the Moon.

Unfortunately, at an altitude of two kilometers, communication with this lander was lost.

Vikram had to land in a plain near the south pole of the moon, of scientific interest, among other things, because it is probable that there you can find water in the form of ice.

Indian space module impact zone on the Moon. Credit: AFP

To analyze the area, in addition to the lander, the mission had a small rover called Pragyan, which had to travel up to half a kilometer across the lunar surface.

NASA confirmed the discovery, by an Indian hobbyist, of the remains of the Chandrayaan-2 space module that crashed while trying to land on the unexplored south pole of the Moon.

When, on September 27, 2019, the NASA-led team posted images of the lunar region where the Indian spacecraft crashed on social media, many people downloaded them to look for signs of the Vikram.

One of those people was the young mechanical engineer and space hobbyist Shanmuga Subramanian, 33, who from the southern city of Chennai and with his personal computer managed to find the lander of the South Asia mission.