Scientists at the University of New Mexico (UNM) and the Massachusetts Institute of Technology (MIT) have discovered and validated two of the longest-period exoplanets TESS has ever discovered. These long-period large exoplanets orbiting K dwarfs belong to the class of planets known as warm Jupiters. It has an orbital period of 10 to 200 days and a radius at least six times that of the Earth. This latest discovery offers exciting future research opportunities in the search for long-period planets similar to our Solar System. The research paper, entitled “TOI-4600 b and c: Two long-period giant planets orbiting early K dwarfs,” will appear in a future issue of The Astrophysical Journal Letters. Exoplanets TOI-4600 b and c were discovered using photometric data from the Transiting Exoplanet Survey Satellite (TESS) and then observed using high-resolution ground-based telescopes. The observing strategy employed by NASA’s TESS will divide each hemisphere into 13 sectors and survey them over about 28 days, making it the most extensive search of the entire sky for transiting planets. This approach has already demonstrated its ability to detect both large and small planets around various types of stars. For TOI-4600, this star is a K dwarf, also known as an orange dwarf, which is slightly smaller and cooler than the Sun.

To be detected by the Science Processing Operations Center (SPOC) pipeline and the Quick Look Pipeline (QLP), exoplanets must pass the host star at least twice within the TESS observation period (2 minutes and 30 minutes ). – Duration of minutes – Browse pipelines. Minute-by-minute cadence TESS data. Most of his discovered TESS exoplanets have periods of less than 40 days, as 74 percent of TESS’s full sky range is observed for only 28 days. Therefore, TOI-4600 b has a period of 82.69 days, or almost 3 months, while TOI-4600 c has a period of 482.82 days, or 16 months, making the discovery even more valuable. Lead author Ismael Mireles of the University of New Mexico analyzed the data, along with Diana Dragomir, assistant professor at the UNM Institute for Physical Astronomy, and collaborators from the Massachusetts Institute of Technology and the University of Bern. Then measure the periods and sizes of these planets. After initially discovering the transits, Mireles and her team had to confirm that they were in fact planets and determine what signals the stars were coming from. A diagnostic tool using TESS showed that the signal from the target was indeed correct. With the help of Subgroup 1 (SG1) of the TESS Tracking Observations Program (TFOP), a worldwide network of professional and amateur astronomers with access to small and large telescopes, they observed the transit and thereby Confirmed by researchers. It means that this planet is actually achieving its goals. Another factor Mireles and his team had to consider was the mass and size of the planet. To do this, instead of speed measurements, they observed how much the host wobbles as it pulls on the planet.

After initially discovering the transits, Mireles and her team had to confirm that they were in fact planets and determine what signals the stars were coming from. A diagnostic tool using TESS showed that the signal from the target was indeed correct. With the help of Subgroup 1 (SG1) of her TESS Tracking Observations Program (TFOP), a worldwide network of professional and amateur astronomers with access to small and large telescopes, they observed the transit, I confirmed it with the researchers. It means that this planet is actually achieving its goals. Another factor Mireles and his team had to consider was the mass and size of the planet. To do this, instead of speed measurements, they observed how much the host wobbles as it pulls on the planet. “There was very little movement in the target star when we took the measurements. So if you start, you could be responsible for what we saw. These 2 Combining the two almost eliminates that possibility, and at that point we were convinced there were two planets,” Mireles said. The researchers found that the two planets, along with the inner planet TOI-4600 b, are 82.69 days long and have radii about just under seven times the radius of Earth. It is between Neptune and Saturn in size. The planet TOI-4600 b has an estimated temperature of about 170 degrees Fahrenheit, which is hot, but colder than many astronomers have found. The second planet found, TOI-4600 c, is about 9.5 times the radius of Earth, or roughly the size of Saturn. When TESS first observed this star, at first he only passed the star once, and almost three years later he passed the second time.

“If you have two passages, you know what the period is like. It could be the 965 days that separate them, the half of it, the third, the quarter, etc. The shorter period may be ruled out because TESS has been observing this star for a long time, leaving only two periods of 965 days or halves,” Mireles explained. The researchers used a model developed by Hugh Osborne of the University of Bern to compare possible orbit times and determine which one was the most likely. They found half of 965 days more likely, or more specifically 482.82 days. With a period of 482.82 days, TOI-4600 c is the longest-period planet TESS has discovered so far, and with a temperature of around minus 110 degrees Fahrenheit, it is one of the coldest planets discovered by TESS. Katharine Hesse, TOI and Review Lead at MIT, collaborated with Mireles and his team on the TESS data analysis. Hesse helped process and analyze large amounts of data, placing the system in the context of other multiplanetary systems discovered on missions such as TESS. Comparing the TOI-4600 system to other discovered exoplanet systems will help investigate features such as formation times and processes, and will help researchers put this system into the broader context of exoplanet systems. It helped me position myself. “It’s important to learn more about planet formation, because based on what we know about exoplanets that have been discovered so far, nothing really resembles our solar system. It’s interesting. , that we want to know about the formation of this planet. There are currently over 5,000 exoplanets, but none of them actually resemble our solar system. So we want to know how these different types of systems formed and migrated,” Mireles said.

These discoveries are of interest to Mireles and the researchers because two long-period giant planets have been discovered. This is an arrangement not often seen by astronomers, but the discovered solar system contained four large long-period planets, or one long-period planet. This leads to further research debates and questions, as Mireles points out. “You want to know how these are formed?” Are there other planets in this system? This means that these giant planets may or may not be there. Can it tell us anything about how it affects small planets that don’t exist, and why they don’t exist? ” Finally, Mireles makes a call to action for citizen scientists and astronomy enthusiasts to get involved and get involved in this research discovery. On Monday, October 16th, another possible transit opportunity will open for those interested in observing this planet, to further confirm that the outer planet’s cycle is indeed 482 days. There will be People with even smaller telescopes can participate if they have the right tools. “There are definitely people who are citizen scientists and amateur astronomers who have their own telescopes and are helping with all these observations.” We are basically confirming that the transit phenomenon is happening in the star,” Mireles said.

source:https://iopscience.iop.org/article/10.3847/2041-8213/aceb69#apjlaceb69s5