- Are there moons in different planetary programs? There have been a rising variety of tentative detections, however none confirmed but.
- There may be new proof for a potential volcanic moon orbiting an enormous planet 635 light-years away. The moon, if actual, is likely to be just like Jupiter’s moon Io.
- An uncommon cloud of sodium fuel close to the planet is finest defined by a volcanic moon, NASA and Caltech astronomers stated.
A volcanic exomoon like Io?
There are lots of of recognized moons in our photo voltaic system, orbiting planets, dwarf planets and even asteroids. However what about in different planetary programs? We nonetheless don’t know for positive, though there have been some tentative detections (however not confirmed but). Now, there could also be new proof for a moon – or exomoon – 635 light-years from Earth. NASA stated on October 10, 2024, that there are potential indicators of a volcanic exomoon – like Jupiter’s moon Io in our photo voltaic system – orbiting the Saturn-sized exoplanet WASP-49 b. The clues come from an uncommon cloud of sodium near the planet.
Researchers with NASA’s Jet Propulsion Laboratory and Caltech in California revealed their peer-reviewed findings in The Astrophysical Journal Letters on September 30, 2024.
The researchers had beforehand reported in regards to the potential moon again in 2019 as properly, however now the proof appears to be even stronger.
An uncommon sodium cloud
The researchers used the European Southern Observatory’s Very Giant Telescope (VLT) in Chile for his or her observations. So how did they conclude there is likely to be a moon orbiting WASP-49 b? The clues got here from a cloud of sodium close to the planet, first detected in 2017. How did it get there? The supply – no matter it’s – is producing about 220,000 kilos (100,000 kilograms) of sodium per second. Each the planet and its star include solely hint quantities of sodium, not almost sufficient to account for the quantity of sodium detected.
So the place else might the sodium come from? The researchers, led by Apurva Oza, previously at NASA’s Jet Propulsion Laboratory and now a workers scientist at Caltech, assume it’s more likely to be a moon orbiting the planet. In that case, it may very well be just like Jupiter’s volcanic moon Io. Io’s volcanoes launch sulfur dioxide, sodium, potassium and different gases into area frequently. They kind diffuse clouds round Jupiter, as much as an unimaginable 1,000 occasions Jupiter’s radius. Might the identical factor be occurring at WASP-49 b? The sodium cloud can be excessive above the planet’s environment. That is just like the fuel cloud that Io’s volcanoes produce close to Jupiter.
Is that this a volcanic moon 635 light-years away? Video by way of NASA/ JPL-Caltech.
A volcanic exomoon for WASP-49?
Within the new examine, the researchers tried to find out what the supply of the sodium cloud is likely to be. That was no straightforward process, given how far-off the planet is from us at 635 light-years. Consequently, it took just a few years of observations of the WASP-49 system to give you the very best reply.
These observations confirmed the sodium cloud was most certainly coming from a physique orbiting the planet, i.e., a moon. On two separate events the analysis workforce discovered the cloud elevated in measurement when it was farthest from the planet. The cloud would seem and disappear behind the planet and the star at irregular intervals. The planet itself, nevertheless, all the time orbits its star each 2.8 days. The researchers used a pc mannequin to strive to determine if a moon may very well be accountable. And certainly, they discovered a moon orbiting the planet about each eight hours would clarify the information.
As well as, the cloud was shifting sooner than the planet itself. This additionally recommended that the cloud originated from a separate physique. The moon could be shifting sooner in its orbit than the planet itself was shifting. Additionally, the cloud was shifting in the wrong way than if it have been one way or the other related to the planet’s environment. As Oza famous:
We expect this can be a actually important piece of proof. The cloud is shifting in the wrong way that physics tells us it must be going if it have been a part of the planet’s environment.
Compelling proof
Co-author Rosaly Lopes is a planetary geologist on the Jet Propulsion Laboratory. She stated:
The proof may be very compelling that one thing apart from the planet and star are producing this cloud. Detecting an exomoon could be fairly extraordinary, and due to Io, we all know {that a} volcanic exomoon is feasible.
The researchers don’t know the way massive the exomoon could also be. However they stated that whether it is comparable in measurement to Earth’s moon (or smaller), then it would doubtless ultimately disintegrate. That is from a mixture of shedding mass by way of its volcanoes and being squeezed by its planet’s gravity. The identical factor occurs on Io, the place Jupiter’s immense gravity squeezes it when it’s closest to the planet. It’s that flexing that retains Io sizzling and molten on the within.
Different potential exomoons
Astronomers reported the first potential exomoon again in 2014. That one, if truly a moon, was orbiting a rogue, free-floating planet. In 2018, the Hubble House Telescope tentatively found the primary exomoon round a planet orbiting one other star, Kepler-1625b. It will be a lot bigger than any moons in our personal photo voltaic system, nevertheless.
Quite a few different potential exomoons have additionally been discovered lately, as EarthSky has reported on. The purported moon for WASP-49 b is simply the most recent, however actually probably the most compelling.
Backside line: Astronomers with NASA and Caltech have discovered {that a} volcanic exomoon could also be producing a cloud of sodium fuel close to an enormous exoplanet 635 light-years away.
Supply: Redshifted Sodium Transient close to Exoplanet Transit
Learn extra: Astronomers uncover 6 potential new exomoons
Learn extra: 1st moon-forming disk round an exoplanet
