For the first time, astronomers have been able to spot a water snowline in a protoplanetary disk surrounding a young star. A protoplanetary disk is massive amounts of cosmic gas, dust and debris that may later form into planets. Water snowline is a point in a star’s orbiting disk of debris where water ice first appears. Astronomers were until now unable to see a snowline because usually the snowlines form closer to the star, whose light makes any observation impossible.

Water Snowline
Image Credit: European Southern Observatory

How researchers found the water snowline

In the case of the star V883 Orionis, a sudden burst of brightness pushed the snowline further out, where it can be seen. Astronomers were able to observe it using the ALMA radio telescope in Chile. The star V883 Orionis is located 1350 light years away from Earth in the constellation Orion. Water snowline plays an important role in planet formation. The rocky debris form planets like Mars and Earth, while the snowy particles on the outskirts give rise to gas giants like Jupiter.

Usually, heat from the young stars evaporates water in the protoplanetary disk up to a distance of 280 million miles. Beyond that point, water turns into ice due to extremely low temperature and pressure. However, the star V883 Orionis had a sudden influx of new material that increased its brightness and heat so much that it evaporated the water up to 3.7 billion miles from its center.

A big surprise for scientists

The far-out boundary allowed astronomers led by Lucas Cieza of the Diego Portales University in Chile to observe the water snowline in radio wavelengths using ALMA. It came as a huge surprise to researchers. Zhaohuan Zhu, the co-author of the study, said it provides direct evidence that a frosty region with conditions conducive to the formation of planets does exist around other stars.

Distribution of water ice around new stars is necessary for planet formation and the development of life as we know it. That’s how our sun got its current collection of planets.