Astronomers discover new class of potentially habitable exoplanets

(CN) — The hunt for signs of life in the expanse of space enjoyed a massive leap forward as experts identified a new type of potentially habitable planet, according to new research revealed Wednesday.

As scientists comb the cosmos for signs of life outside the boundaries of Earth, finding planets that most closely resemble our own has been the name of the game. Experts have spent years trying to find planets that fall inside the so-called “Goldilocks zone” for habituality, a reference to the countless planetary components — like oxygen levels, climate status and even distance from nearest star — that need to be just right in order for life to exist.

Locating these Goldilocks planets has often proved to be a taxing task for astronomers, but many have assumed the best candidates are those that share the most in common with Earth. A safe bet, in the eyes of some, considering that despite years of searching, Earth stands as the only planet we know of with life.

But now, researchers from the University of Cambridge are challenging that notion.

In a study published in the Astrophysical Journal, experts reveal they’ve identified a class of exoplanets that are shockingly different from Earth but may in fact still have the right concoction of ingredients to support life.

Researchers have dubbed the new bodies Hycean planets and the differences between them and Earth are almost literally night and day. Hycean planets are distinguished by their massive size, hot temperatures and are almost completely covered in oceans. Some known as dark Hycean worlds even come equipped with a side of their planet that is forever trapped in nighttime.

Nikku Madhusudhan from Cambridge’s Institute of Astronomy who led the research says these difference from Earth may be extreme and fly in the face of previous expectations of what a life-supporting planet could look like, but maintains their life-supporting qualities can’t be ignored.

“Essentially, when we’ve been looking for these various molecular signatures, we have been focusing on planets similar to Earth, which is a reasonable place to start,” Madhusudhan said in a statement. “But we think Hycean planets offer a better chance of finding several trace biosignatures.”

Experts believe that despite their warmer atmospheric temperatures, which can reach up to nearly 400 degrees Fahrenheit, the oceans on Hycean planets may be mankind’s best hope in finding alien life. The vast waters of a Hycean planet’s oceans may operate under very similar conditions to those of Earth’s oceans and — not unlike Earth — they may house microbial life in their deepest depths.

Scientists say they also might find life on colder Hycean worlds that receive little radiation from stars or even on the worlds with permanent night, as those temperature changes might open up new doors for life to take hold.

But arguably the biggest surprise in all of this, according to experts, is just how common these planets are. Scientists have known for decades about numerous exoplanets called “super-Earths” or “mini-Neptunes” but they’ve been largely written off as being life-supporting because of their high pressures and temperatures.

Now, however, researchers from Wednesday’s study reveal that an investigation into these exoplanets show many of them may hold the secret to supporting life after all.

With a new batch of targets to focus on, researchers say it is only a matter of time before advancements in telescope technology allows us to accurately look for biological signatures on these hot giants. And once we do, we need to be prepared for what we may encounter.

“A biosignature detection would transform our understanding of life in the universe,” Madhusudhan said. “We need to be open about where we expect to find life and what form that life could take, as nature continues to surprise us in often unimaginable ways.”

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