Strong flashes of hot gas in young red dwarfs can make living conditions on new planets unsuitable. Artistic vision shows an active young dwarf (right) destroying the atmosphere of an orbital planet (left). Scientists have found that flares from young dwarfs (40 million years) are 100–1000 times more energetic than those of older stars.
The word HAZMAT is used to describe substances that are dangerous to the environment or life itself. The term also applies to all planets where outbursts of violence by a host star can make the world uninhabitable by affecting their atmosphere. The NASA Hubble Space Telescope observes such stars through a special program HAZMAT (habitat zones and active M-dwarfs).
M-dwarf is a red dwarf star, which is considered the smallest, most common and most long-lived star in the galaxy. The HAZMAT program is an ultraviolet (UV) examination of red dwarfs in three different age groups: young, medium and ancient. Star flashes of red dwarfs are especially bright in UV waves compared to stars of the solar type. Hubble's UV sensitivity makes the telescope valuable for viewing such flashes. It is believed that the flashes feed on intense magnetic fields entangled during the rotation of the stellar atmosphere. When the entanglement becomes too intense, the fields break down and reunite, releasing a large energy flow.
The team noticed that flares from the youngest red dwarfs (40 million years old) are 100–1000 times more energetic than those of older stars. This is the youngest age when earthly planets form around stars. About 3/4 stars of the Milky Way are red dwarfs. Most of the planets rotating in the habitat zone (there is an opportunity for the presence of liquid water) are likely to live near red dwarfs. The star closest to the Sun is Proxima Centauri, which is of the red dwarf type and has an Earth-like planet in its habitat zone.
But still we are talking about active stars that produce UV-flash, whose energy can affect the chemistry of the atmosphere and even destroy the atmospheric layer itself. The goal of the HAZMAT program is to help understand the habitability of planets around low-mass stars. The new study examined the frequency of outbreaks of 12 young red dwarfs. The observation showed one of the most intense star flares in UV light, surpassing the solar readings over the entire study period. Can flashes of red dwarfs destroy lives on other planets? Scientists believe that the observed events can remove the atmospheric layer and condemn the potential life worlds to death. Or there lives a completely different life that does not need an atmosphere.
The next part of the study will study the red dwarfs of middle age (650 million years). Then scientists will take up the old stars, comparing with previous indicators, to understand the evolution of the environment of UV radiation.