Chandrayaan 1 Current Affairs

Scientists create first global map of water on Moon

Scientists from Brown University in US have created first map of water trapped in uppermost layer of Moon’s soil. The  was build using NASA’s Moon Mineralogy Mapper onboard of India’s Chandrayaan-1 spacecraft.

The map builds on initial discovery of water and related molecule — hydroxyl (consists of one atom each of hydrogen and oxygen) in lunar soil in 2009. It may prove useful to future lunar explorers.

Water Presence on Moon

The signature of water is present nearly everywhere on lunar surface and not limited to polar regions as it was previously reported. The distribution of waster on moon is largely uniform rather than splotchy. The way in which it is distributed across Moon gives clues about its source.

The amount of water on moon increases toward poles and does not show significant difference among distinct compositional terrains. It reaches a maximum average of around 500 to 750 parts per million (ppm) in higher latitudes, less than what is found in sands of Earth’s driest deserts.

However, its concentrations gradually decrease toward equator. This pattern is consistent with implantation via solar wind from Sun, which can form hydroxyl (OH) and molecular water once emplaced.

Bulk of water mapped in this study can be attributed to solar wind with some exceptions. For example, higher-than-average concentration of water was found in lunar volcanic deposits near Moon’s equator, where water in surrounding soil was scarce. In this case, it is assumed that water comes from deep within Moon’s mantle and erupted to surface in lunar magma rather than coming from solar wind.

The concentration of water also changes over course of lunar day at latitudes lower than 60 degrees, going from wetter in early morning and evening to nearly bone dry around lunar noon. The fluctuation can be as much as 200 ppm.

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NASA scientists found lost Chandrayaan-1 orbiting Moon

Scientists at NASA’s Jet Propulsion Laboratory (JPL) have found India’s first lunar probe, Chandrayaan-1 which was considered lost, is still orbiting the moon. They also have found NASA’s Lunar Reconnaissance Orbiter (LRO).

The ISRO lost communication with Chandrayaan-1 on August 29, 2009, almost a year after it was launched on October 22, 2008. The unmanned spacecraft is still circling some 200 km in the polar orbit around the moon

How these probes were discovered?

Both space probes were discovered using JPL’s new ground-based radar technique by sending out a powerful beam of microwaves towards the moon. The beams were produced using 70-metre antenna at NASA’s Goldstone Deep Space Communications Complex in California. The radar echoes bounced back from lunar orbit were received by the 100-metre Green Bank Telescope in West Virginia.

Key facts
  • The LRO was easily discovered as scientists were working with the mission’s navigators had precise orbit data.
  • But finding of Chandrayaan-1, very small and cuboid in shape, about 1.5 metres in length on each side was little bit difficult as ISRO had last contact with it.
  • Even finding a derelict spacecraft at lunar distance that has not been tracked for years is tricky because the moon is riddled with
  • Mascons are regions with higher-than-average gravitational pull. It is believed that they may had dramatically affected spacecraft’s orbit over time, and even cause it to crashed into the moon. 
Background

Chandrayaan 1 after its launch in October 2008 had operated for 312 days, as against the intended two years, but the mission achieved 95% of its planned objectives. It had sent more than 70,000 images of the lunar surface which provided breathtaking views of lunar mountains and craters, especially craters in the permanently shadowed areas of the Moon’s polar region.

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