Oct. 11 () –
The existence of a moon located outside our solar system has never been confirmed, but a new NASA-led study may provide indirect evidence for it.
New research conducted at NASA’s Jet Propulsion Laboratory (JPL) reveals possible signs of a rocky volcanic moon orbiting an exoplanet 635 light years from Earth.
The most important clue is a sodium cloud that, according to the findings, is close to the exoplanet, a Saturn-sized gas giant called WASP-49 b, but slightly out of sync with it, although more research is needed to confirm the behavior of the cloud. Within our solar system, gas emissions from Jupiter’s volcanic moon Io create a similar phenomenon..
Although the existence of exomoons (moons of planets outside our solar system) has not been confirmed, multiple candidates have been identified. These planetary companions have likely gone unnoticed because they are too small and faint for current telescopes to detect.
The sodium cloud around WASP-49 b was first detected in 2017, which caught the attention of Apurva Oza, former postdoctoral researcher at NASA’s Jet Propulsion Laboratory and now a scientist at Caltech, which manages JPL.
Oza has spent years researching how exomoons can be detected through their volcanic activity. For example, Io, the most volcanic body in our solar system, constantly spews sulfur dioxide, sodium, potassium and other gases that can form enormous clouds around Jupiter up to 1,000 times the radius of the giant planet.. It’s possible that astronomers observing another star system could detect a gas cloud like Io’s even if the moon itself were too small to see.
Both WASP-49 b and its star are composed primarily of hydrogen and helium, with traces of sodium. None of them contain enough sodium to explain the cloud, which appears to come from a source that produces approximately 100,000 kilograms of sodium per second. Even if the star or planet could produce that much sodium, it’s unclear what mechanism could eject it into space.
COULD THE SOURCE BE A VOLCANIC EXMOON?
Oza and his colleagues set out to try to answer the question of whether it could be a volcanic exomoon. The work was immediately challenging because, from such a great distance, the star, planet and cloud often overlap and occupy the same tiny, distant point in space. Therefore, the team had to observe the system over time.
As detailed in a new study published in Astrophysical Journal Letters, they found several pieces of evidence suggesting that the cloud is created by a separate body orbiting the planet, although more research is needed to confirm the behavior of the cloud.
For example, twice their observations indicated that the cloud suddenly increased in size, as if it were refueling, when it was not next to the planet.
They also observed that the cloud was moving faster than the planet in a way that would seem impossible unless it was generated by another body that was moving independently of the planet and faster than it.
“We think this is a really crucial test. The cloud is moving in the opposite direction that physics tells us it should go if it were part of the planet’s atmosphere.”“says Oza.
Although these observations have intrigued the research team, they say they would need to observe the system for longer to be sure of the orbit and cloud structure.
Add Comment