May 16, 2018

Why in news?
The spacecraft, known as the Star-Planet Activity Research CubeSat, or SPARCS, is a new NASA-funded space telescope and will be launched in 2021 .
The satellite will monitor the flares and sunspots of small stars called M dwarfs to assess how habitable the environment is for planets orbiting them.
The stars that SPARCS will focus on are small, dim, and cool by comparison to the Sun. Having less than half the Sun’s size and temperature, they shine with barely one per cent its brightness.
Astronomers have discovered that essentially every M dwarf star has at least one planet orbiting it, and about one system in four has a rocky planet located in the star’s habitable zone.
Since M dwarfs are so plentiful, astronomers estimate that our galaxy alone contains roughly 40 billion rocky planets in habitable zones around their stars. This means that most of the habitable-zone planets in our galaxy orbit M dwarfs.
Need for SPARCS
Although the orbiting Hubble Space Telescope can view stars at ultraviolet wavelengths unhindered, its overcrowded observing schedule would let it dedicate only the briefest of efforts to M dwarfs.