Posted on behalf of Ashley Yeager

Aside from feeling the love, the Indian Space Research Organization’s first unmanned lunar orbiter, Chandrayaan-1, is now feeling the heat. Some of the probe’s systems have been shut off as temperatures aboard the spacecraft reached 49 degrees Celsius.

The increase was not unexpected, Mylswamy Annadurai, the project director for the lunar mission, told CNN.

Spacecraft typically heat up because as the craft, the moon and the sun line, the probes receive infrared radiation from the Moon as well as energy directly from the Sun. The spacecraft is currently orbiting the moon’s sunlit side and facing external temperatures of 100 degrees Celsius, Annadurai said.

He explained that temperatures aboard Chandrayaan-1 should not surpass 50 degrees Celsius, but noted that the orbiter is designed to withstand up to 60 degrees Celsius. To maintain a safe temperature, however, Chandrayaan-1 has cooling systems that aim to keep the spacecraft’s interior at 40 degrees Celsius.

The craft has since cooled to that temperature. But as a preventative measure and to rule out the possibility of damage to spacecraft, mission scientists have switched off onboard systems that do not necessarily need to be on. Also, because of the heat, scientists will use only one instrument aboard Chandrayaan at a time until temperatures stabilise in late December.

Nine of the 11 onboard instruments have been switched on for checks on their health and calibration. Annadurai told The Economic Times that perhaps by mid-January scientists will be able to operate all instruments simultaneously.

Image: detail from moon photo acquired Chandrayaan-1 on 16 Nov. 2008 / ISRO