Scientists from National Institute of Standards
and Technology’s (NIST) have developed an Astrocomb. It is a custom made
frequency comb which can precisely measure frequencies or colours of light.
The instrument will help the precision needed
for discovering and characterising planets orbiting M dwarf stars. M dwarfs
(also known as red dwarfs) are the most common stars, comprising nearly 70% of
all the stars in the Milky Way Galaxy.
A star’s nuclear furnace emits white light. This
light is modified by elements in the atmosphere that absorb certain narrow
bands of colour. There are oscillations in colour due to the gravitational pull
of an orbiting planet. Astronomers look into these periodic changes in colour to
search for planets orbiting distant stars.