Scientists have discovered a planet that could have good conditions to support life, and it is one of the closest known planets around Earth. The planet, called GJ 3378b, is about 25 light-years away, and is very close to the Milky Way.
It is roughly twice the size of Earth, and orbits its star in the habitable zone around the Sun, where temperatures can allow liquid water to exist. The planet also receives about 90% of the sunlight that Earth receives from the Sun. For this reason, astronomers say it is one of the most promising nearby planets in the search for life outside our solar system.
What scientists have discovered about GJ 3378b and why it matters
The study, published in The Astrophysical Journal and titled “Mass and Revised Period of the Habitable Zone of Super-Earth GJ 3378 b: A Planet Stretching the Cosmic Shoreline,” was led by Paul Robertson, associate professor of astronomy at the University of California, Irvine.
The researchers updated previous measurements and found that the planet’s mass is about 2.3 times the mass of Earth. They also confirmed that it orbits within the habitable zone around its star, also known as the Goldilocks zone, where conditions may be suitable for liquid water.“It’s one of our closest cosmic neighbors. Twenty-five light-years seems like a long way, but the width of the Milky Way is about 100,000 light-years, so in that respect it’s our next-door neighbor,” the New York Post reported.
The team made the discovery using two ground-based instruments: the Habitable Zone Planet Detector on the Hobby-Eberly Telescope in Texas, and the NEID Spectrometer on the WIYN Telescope in Arizona. The research was funded by the National Science Foundation and NASA.
Why is the atmosphere of GJ 3378b so important in the search for life?
Although GJ 3378b looks promising, scientists still don’t know something very important: whether it has an atmosphere or not. Without an atmosphere, liquid water is unlikely to exist on the planet’s surface, making life as we know it much less likely.The planet is located near what scientists call the cosmic coastline. This is the point at which radiation from the star can slowly strip away the planet’s atmosphere. Mars is an example from our solar system. Scientists believe it once had a thicker atmosphere, but over billions of years, much of it was lost to radiation.Robertson explained how thin the atmosphere is by comparing the Earth to an apple. He said that if the Earth were the size of an apple, its atmosphere would be as thick as an apple’s skin.
Although it is very thin, it is enough to create the pressure necessary for liquid water to exist.
When will scientists know if GJ 3378b can support life?
Scientists say the answer will take time. Currently, no space telescope is able to confirm whether GJ 3378b has an atmosphere.This mission is expected to be carried out by NASA’s Habitable Worlds Observatory, which is currently expected to launch in the 2040s. The telescope will be able to take direct images of planets like GJ 3378b and study their atmospheres in detail.If scientists confirm that the planet has an atmosphere, they will next look for biosignatures. These are chemicals found in the planet’s atmosphere that can be produced by living organisms.“I think that’s very interesting,” Robertson said while talking about the possibility of searching for signs of life.This discovery also adds GJ 3378b to the growing list of nearby planets that future space telescopes will study.
Robertson said scientists are still exploring our near cosmic neighborhood, looking for planets around the closest stars because they are the easiest places to look for signs of life.For now, GJ 3378b remains one of the most exciting nearby planets yet discovered. It’s the right size, located in the right part of its star system, and receives roughly the same amount of energy from the Sun as Earth. Whether it can actually support life is a question scientists hope to answer in the future.