James Webb finds the missing element for life on the moon Europa

Portada Carbono en Europa

Jupiter's moon Europa is one of the most interesting places in the solar system from an astrobiology point of view. It is one of the largest known deposits of liquid water, which is key to life as we know it on Earth. However, the rest of the necessary element compounds had never been detected. The James Webb Space Telescope found traces of carbon dioxide for the first time, which must have formed recently.

Photograph of Europa obtained by the NIRCam instrument on the James Webb Space Telescope. The white regions correspond to Tara Regio (right) and Powys Regio (left). Credits: NASA, ESA, CSA, G. Villanueva (NASA/GSFC), S. Trumbo (Cornell Univ.), A. Pagan (STScI).

Europe: a frozen world

Among the dozens of moons that constantly orbit Jupiter, Europa is part of those known as Galileans and is the second in proximity to the gas giant. It is tidally coupled, that is, it always offers the same face to the planet.

It has a relatively thin ice shell that protects an extensive ocean of salty liquid water. Thanks to the joint work of probes such as Galileo, Cassini and Juno, and space telescopes such as Hubble, There has been enormous interest in understanding the chemistry that takes place in the interior of Europe. Being one of the main sites in the solar system with the potential to give way to life.

jupiter hi res atmo 1
First photograph of Jupiter taken by James Webb. Europe appears on the left side. Its ice crust reflects a large amount of infrared light, showing great brightness. Credits: NASA, ESA, CSA.

Carbon: pillar of life

Organic chemistry focuses on the study of the interactions between elements that make life possible. Such as oxygen, hydrogen, carbon, phosphorus, nitrogen and sulfur. It is necessary to have all of them so that the necessary reactions can occur to form molecules and, later, living beings.

A team of researchers took advantage of James Webb's incredible resolution and sensitivity to analyze compounds present in Europa. They achieved iidentify the presence of carbon dioxide on the frozen surface. Different analyzes ruled out external sources such as meteorites as a possible origin. Confirming for sure that it must come from the underground ocean.

Plot of NIRCam (left) and NIRSpec observations at wavelengths associated with crystalline carbon dioxide. Credits: NASA, ESA, CSA, G. Villanueva (NASA/GSFC), S. Trumbo (Cornell Univ.), A. Pagan (STScI).

Observing at different wavelengths, a map was made that shows the intensity of light emission associated with crystalline carbon dioxide.. The main location being the region known as Tara Regio, an area classified as chaotic terrain. In this there is a constant interaction and exchange of matter between the inner ocean and the outer crust.

Carbon dioxide is not stable on the surface of Europa, so researchers assume it must have formed recently, in terms of geological time scales. Although carbon is one of the most common elements in the universe, it is a good indicator of the possibility of the presence of life on the moon.

A hope for life

Carbon is a fairly abundant element in the atmospheres and surfaces of all the planets in the solar system, both rocky and gaseous. The discovery lays the foundation for future observations by the Europa Clipper and JUICE probes, which will study the intriguing moon up close. More tests and observations are still needed to determine if life really exists outside of Earth.

Francisco Andrés Forero Daza