Extrasolar planet studies has grown by leaps and bounds. A total of 5,090 exoplanets have been confirmed and another 8,933 are waiting to be confirmed. There have been Neptune-like gas giants (1,779), gas giants comparable to Jupiter or Saturn (1,536), and rocky planets many times the size of Earth. The transit method is the most effective way to find planets. When a planet passes in front of a star, it is known as a transit photometry.

An international team of astronomy has discovered a three-planet system around a Sun-like star. The team theorizes that the exoplanets consist of a rocky planet several times the size of Earth and two gas giants smaller than Neptune. This system is close enough to be ideal for follow-up studies and characterizations with theJWST.

An artist’s illustration of the mini-Neptune TOI 560.01 losing its atmosphere and transitioning to a super-Earth. Credit: Adam Makarenko (Keck Observatory)

The paper that describes the findings of the research was published online. The two mini Neptunes, designated TOI 411.01) and 411.02 (planets c and b), were identified using TESS data and were found to have an average orbital period of 9.27 and 4.14 days, respectively. There was a signal that indicated the presence of a third planet with a period of about 46 days. Cacciupoti sent an email to Universe Today.

Two planets were found by the first automated search. I was working on another project related to TESS at the beginning of the 21st century. This is a citizen science project with which we analyzed TESS candidates to find false positives.

There is a new signal in the lightcurve of TOI-411 that may be a sign of a third planet. Ordinarily, an astronomer would try to confirm a transit signal using the radialvelocity method, where the parent star's data is compared to the observer's data. This is used to calculate the force acting on the star from a planetary system. Cacciupoti said, "Yes."

The paper made the best use of TESS data as well as other ground-based observations. We didn't use high-resolution spectrum of the star, but we did eliminate any other possibilities that could cause the signal. The signal might be caused by stellar spots, but we didn't use them.

Artist’s impression of a Super-Earth orbiting the Sun-like star HD 85512 in the southern constellation of Vela (The Sail). Credit: ESO

The stability of the planetary system was determined using N-body simulations. Computer simulations were used to see if the planets would survive or if there would be instability. They looked at the dynamics of planetary systems to see if pairs of planets could host more than one.

The criterion allows us to determine if there's enough space for a fourth planet. There are several examples in literature in which new planets were found with different techniques that eclipses couldn't find.

Cacciupoti and his colleagues hope to conduct follow-up observations of this system using a 3.6 meter telescope at the La Silla Observatory. The transit method can only be used to find exoplanets around bright stars. They hope to take advantage of the space telescope's advanced technology.

When it comes to obtaining spectrum from distant exoplanets, Webb has shown its ability. Analyzing the atmosphere of exoplanets will help determine if they can support life. The fact that HOI 411 is a Sun-like star and has a multi-planet system makes it a prime target for follow-up studies.

Finding good candidates to search for planets that have atmospheres can be difficult if we don't know which ones. We use information on the star, the planet, and its path to predict the strength of the atmosphere as seen by the JWST. One of the highest predicted strengths for an atmospheric signal among the planets of its kind is that of planet TOI-411 c.

ArXiv is further reading.