When sun-like stars die, they devour and destroy the planets closest to them.
Planets caught up in the huge gravitational force of a white dwarf star appear to be metal pollution around these burned stars. To reconstruct the metal composition of such already extinct exoplanets and other rock-based planets, he is helping researchers with lithium and potassium markers in the contamination of white dwarfs.
A white dwarf is what’s left of a small star after it consumes its fuel – converting all its hydrogen into helium, and helium into carbon and oxygen, and shedding its outer layers. The remnant of the stellar nucleus is extremely dense; its mass can be the mass of the sun, but its volume can be the volume of the Earth.
Usually, the gravitational force of white dwarfs quickly collapses below the surface of elements heavier than hydrogen and helium. But in some cases, white dwarfs have signs that their atmosphere is polluted by heavy elements. This pollution is associated with the Dead star after it pulls and consumes rock systems from the planetary system around it.
By measuring the amounts of lithium, sodium, potassium and calcium around the contaminated white dwarf, scientists have determined the abundance of elements found on ancient exoplanets, where metals originated. This is especially important, it is possible to understand the abundance history of lithium, which is less specific than other elements.
Considering that most of the metals were formed five minutes after the Big Bang, it seems that lithium was consumed by stellar nuclear reactions. Planets and other rocky elements store lithium. Because our solar system is only 4.5 billion years old, we can do this by studying stars or exoplanets that are too old to look at the history of the metal.