Vikram sends back first moon readings
India's Chandrayaan-3 mission has recorded temperatures on the lunar surface, offering new insights into the Moon's thermal behavior and characteristics of lunar soil. The temperature dropped significantly as the probe dug deeper into the lunar surface, with temperatures of around 55°C at the topmost level and around -10°C at a depth of about 8cm. The experiment is set to continue for 10 more days.
Chandrayaan-3’s Vikram lander module has recorded temperatures at various layers of the lunar surface, the Indian Space Research Organisation (Isro) said on Sunday, in the first such experiment that is set to offer new insights into Moon’s thermal behaviour and characteristics of lunar soil, especially close to its south pole.
The temperature graphs, released by the space agency on Sunday, revealed that the temperature dropped significantly as the probe dug deeper into the lunar surface, which, while not unexpected, is the first time it has been quantified minutely.
“Chandrayaan-3 Mission: Here are the first observations from the ChaSTE payload on-board Vikram Lander. ChaSTE (Chandra’s Surface Thermophysical Experiment) measures the temperature profile of the lunar topsoil around the pole, to understand the thermal behaviour of the moon’s surface,” Isro said in a statement on Sunday.
The ChaSTE payload, one of the four on board Vikram, was designed to measure how the lunar surface absorbs heat, which it did so by measuring the temperature a little above the surface, and then at various intervals as the probe dug up till about 8cm into the ground.
“ChaSTE has a temperature probe equipped with a controlled penetration mechanism capable of reaching a depth of 10 cm beneath the surface. The probe is fitted with 10 individual temperature sensors,” Isro said.
According to the findings relayed to Isro by Vikram, a temperature of around 55°C was recorded at the topmost level of the reading, which was a little above the ground level. At a depth of about 8cm, the temperature fell to around -10°Celsius, the data showed.
“The presented graph illustrates the temperature variations of the lunar surface/near-surface at various depths, as recorded during the probe’s penetration. This is the first such profile for the lunar south pole. Detailed observations are underway,” the agency said.
The payload was designed by scientists at Isro’s Space Physics Laboratory in the Vikram Sarabhai Space Centre and the Physical Research Laboratory.
Apart from measuring heat flows on the lunar surface, and the temperature of the regolith (loose soil and rock debris that blankets the bedrock), ChaSTE will also provide data on the characteristics of lunar soil.
Isro activated the payload on August 24, a day after the lander made a successful soft landing near the south pole of the Moon, making India the first country in the world to achieve the feat.
The experiments are scheduled to go on for 10 more days, till the lunar sunset, Isro chief S Somanath said.
“We have around 10 more days of experiments to go and during the course we will be receiving some very critical data. The lander and the rover are also sending a lot of pictures from the lunar surface, some unique ones that have never been taken so far. Our data network teams are processing those,” Somanath said.
Apart from ChaSTE, the lander is carrying the Instrument for Lunar Seismic Activity (ILSA) for measuring the seismicity around the landing site and the Langmuir Probe (LP) to estimate the plasma density and its variations. A passive Laser Retroreflector Array from the National Aeronautics and Space Administration (NASA) has also been accommodated for lunar laser ranging studies.
The rover, on the other hand, has the payload of the Alpha Particle X-ray Spectrometer (APXS) and Laser Induced Breakdown Spectroscope (LIBS) for deriving the elemental composition in the vicinity of landing site.