Exoplanet Orbiting a White Dwarf Star Gives Researchers Hope That Earth Might Escape Its Eventual Death

A planetary system with a white dwarf star at its center, 4,000 light-years from Earth, gives astronomers their best clue yet about what is expected to happen to our Sun and Earth 8 billion years from now. The scenario comes if Earth survives the red giant phase of Sun, expected to happen in 5 to 6 billion years. In this phase, the Sun is expected to expand to such an extent that it would engulf Mercury and Venus and most probably earth before shriveling into a white dwarf.

The Prospects of Survival of Earth

According to a recently published study in the journal Nature Astronomy, Earth would need to be flung out into a Mars-like orbit or beyond, essentially abandoning it to become a scorched over and frozen world revolving around a burnt-out star. The newly found system presents an Earth-sized planet orbiting a white dwarf of half the mass of the Sun, with this describing how the Earth could look, should it survive this integration.

That makes this potential candidate for a planetary engulfment event even exciting, given the fact that there has been no consensus on whether Earth would escape being swallowed by the red giant Sun. The system includes a huge companion, believed to be a brown dwarf, that is a stellar body having failed to ignite nuclear fusion.

Discovery Process

The planetary system was discovered through a microlensing event, in which the gravitational effect of a body causes the bending of light coming from a more distant source. This event is called KMT-2020-BLG-0414, and observations were performed using the Korea Microlensing Telescope Network; the observation was pursued up to the Keck telescopes in Hawaii with sufficient data to determine that the central star of this system is a white dwarf, since no light is seen coming from it as expected of a main sequence star.

Future Habitable Possibilities

This discovery goes to show that Earth is actually save from destruction. But the question that could be presented is whether or not the life on this Earth can exist or not. According to Jessica Lu, an astronomer from the University of California in Berkeley, the Earth might not get engulfed during the red giant phase, but it might not even be a habitable one at that time. The habitable zone will move past Earth’s orbit, with the suggestion being that humans may soon need to contemplate settling upon the moons of Jupiter or Saturn when those become potentially ocean worlds once the Sun expands.

Conclusion

This work demonstrates the relevance of microlensing in studying planetary systems. The Nancy Grace Roman Telescope, to be launched in 2027, is believed to improve significantly exoplanet discovery and study, and potentially shows how the universe can have other unique configurations.

Related