Many of us take the Earth and its many ‘normal’ characteristics for granted, but there are so many exoplanets in the universe around us with their own unique chemical and physical properties that many may seem out of this world (pun intended). Take for example WASP-76b, an exoplanet residing 640 light-years away from Earth with such hellish conditions that the skies don’t rain liquid water, but rather molten iron.
Astronomers took their first glance at WASP-76b with the help of the ESPRESSO instrument on the European Southern Observatory’s Very Large Telescope in Chile. Upon making observations, they ascertained that WASP-76b was twice as large as Jupiter and the host star it orbits very closely is approximately twice as large as our Sun.
It only takes WASP-76b about 1.8 Earth days to complete an orbit around its star, and it’s probably tidally locked. Orbiting so close to such a star equates to receiving 4,000 times the solar radiation that Earth does from the Sun, and consequently, temperatures on WASP-76b reach a blistering 4,350º Fahrenheit (or 2,400 Celsius).
As for how astronomers knew about the molten iron rainstorms, it all comes down to the observations. While using telescopes to look at distant exoplanets, the star’s light passes through their atmospheres. Astronomers also know that certain atoms block certain wavelengths of light, so with this (a method called spectroscopy), it can be determined what the atmosphere might be comprised of.
A world as hot at WASP-76b is unquestionably uninhabitable, but at the same time, it’s difficult to imagine the existence of a world in which liquid metal falls rains from the skies. As it would seem, the temperatures are just so great that the metal is quite literally vaporized and then transferred to other regions of the world’s atmosphere via wind where it then cools down and falls back down toward the center of gravity.
What an amazing universe we live in…
