You can search by either selecting keyword only or dates only or with both keyword and dates.
You cannot select "news" previous than 1st March 2016.


How is geotail helping Chandrayaan-2 learn about Moon (Relevant for GS Prelims; Science & Technology)

The geotail is a region in space that allows the best observations. The region exists as a result of the interactions between the Sun and Earth. On its website, ISRO explains how the region is formed, and how it helps scientific observations.

LAST WEEK, the Indian Space Research Organisation (ISRO) tweeted that an instrument on Chandrayaan-2, CLASS, designed to detect signatures of elements in the Moon’s soil, had detected charged particles during the mission. This happened in September, during the orbiter’s passage through the “geotail”.

The geotail is a region in space that allows the best observations. The region exists as a result of the interactions between the Sun and Earth. On its website, ISRO explains how the region is formed, and how it helps scientific observations.

The Sun emits the solar wind, which is a continuous stream of charged particles. These particles are embedded in the extended magnetic field of the Sun. Since the Earth has a magnetic field, it obstructs the solar wind plasma. This interaction results in the formation of a magnetic envelope around Earth (see illustration). On the Earth side facing the Sun, the envelope is compressed into a region that is approximately three to four times the Earth radius. On the opposite side, the envelope is stretched into a long tail, which extends beyond the orbit of the Moon. It is this tail that is called the geotail.

Once every 29 days, the Moon traverses the geotail for about six days. When Chandrayaan-2, which is orbiting the Moon, crosses the geotail, its instruments can study the properties of the geotail, ISRO said.

For the CLASS instrument seeking to detect element signatures, the lunar soil can be best observed when a solar flare provides a rich source of X-rays to illuminate the surface. Secondary X-ray emission resulting from this can be detected by CLASS to directly detect the presence of key elements like Na, Ca, Al, Si, Ti and Fe, ISRO said.

Source: The Indian Express



en_USEnglish
hi_INहिन्दी en_USEnglish