Tag Archive : Necro planetology

necroplanet

Necro planetology

5 yrs back, scientists discovered a white dwarf star 570 light-years away from Earth. They noticed that the star was dimming at an irregular rate. Closer inspection revealed that the star is devouring the planets in its solar system through a process called tidal disruption.

The discovery was the beginning of a brand new scientific field called the Necro planetology. This term is like placing the word “dead” in front of planetary studies.

A team of researchers from Wesleyan University in Connecticut, the University of Colorado, Boulder, and Warwick University in the U.K. first published the findings on the pre-print website arXiv in 2015. Now this research has been accepted by the Astrophysical Journal for review. They say that this discovery may help in understanding how planets in different systems are gobbled up by parent stars.

Before going into a supernova or turning into a black dwarf, dying stars become white dwarves. In about 6 billion years that would be the fate of our sun also. The atmospheres of these stars usually contain lighter elements such as helium and hydrogen.

Scientists did the research on several clues. One of these clues was that the dimming occurred repeatedly, every 4.5 to 5 hours. The second clue was, that the star’s atmosphere was littered with elements typically found in the cores of rocky exoplanets—heavy elements like iron, oxygen, and magnesium.

To study how these planets met their doom, the researchers created a series of computer simulations. This simulation mapped how 36 different types of planets endured these conditions. For each of these 36 planets in the simulation, they set the orbital period to about 4.5 hours. They ran the simulation 100 times.

According to the results of the simulation, rocky bodies with a tiny core and low-density mantle were the most likely to produce the observations they saw before. These high-density planets are similar to rocky asteroids like Vesta. These are tough enough to endure the bulk of the disruption. But these disintegrate within a short period of time.

WD 1145+017 is not the only star with such a huge appetite. Astronomers observed 21 stars with similar behavior.