HomeNewsAstronomy and SpaceTwo exoplanets orbiting a sun-like star found

Two exoplanets orbiting a sun-like star found


HARPS (orange) and CORALIE (blue) radial velocities. In this determine, we current our RV time sequence. As is clearly seen, the info present a long-term and high-amplitude pattern (semiamplitude of ~ 200 m s-1), typical of the signature of an extended interval big planet. Credit: arXiv:2111.08764v1 [astro-ph.EP]

An worldwide staff of astronomers experiences the detection of two new exoplanets orbiting an developed sun-like star often known as HD 137496. The newly discovered extrasolar worlds, recognized utilizing NASA’s Kepler spacecraft, had been labeled as sizzling super-Mercury and chilly Jupiter. The discovery is detailed in a paper printed November 16 on arXiv.org.


Kepler is essentially the most prolific planet-hunting telescope because it has found greater than 2,600 exoplanets up to now. After the failure of its two response wheels in 2013, the mission was repurposed as K2 to carry out high-precision photometry of chosen fields within the ecliptic. The revived Kepler spacecraft, which operated until November 2018, has detected a whole lot of recent extrasolar worlds.

Now, a gaggle of astronomers led by Tomas Silva of the University of Porto, Portugal, experiences the detection of one other two recognized by K2. The discovery was made when the telescope noticed HD 137496 (also referred to as K2-364), a mid-G star close to the primary sequence turn-off, as a part of the Campaign 15 of the K2 mission from August 23, 2017 to November 19, 2017. The observations revealed transit alerts within the mild curve of HD 137496, and planetary nature of those alerts was confirmed by radial velocity (RV) observations from the HARPS and CORALIE spectrographs.

“We report the discovery of a planetary system orbiting HD 137496 (K2-364). With photometry from K2 and precise RVs from both HARPS and CORALIE spanning over two years, we are able to accurately characterize the stellar host, study its chemical composition, and put strong constraints on the planetary companions,” the researchers wrote within the paper.

The exoplanet nearer to the star, designated HD 137496 b is about 30 % bigger than the Earth and round 4 occasions extra large than our planet, what offers density at a degree of 10.49 g/cm3. This planet consists primarily of iron, with the core representing over 70 % of the thing’s mass. HD 137496 b orbits its host each 1.62 days, at a distance of about 0.027 AU from it, therefore its equilibrium temperature is estimated to be some 2,130 Ok. Therefore, the extrasolar world was labeled as a sizzling super-Mercury—an Earth-sized planet with the density of the solar system’s smallest planet.

The second newly found exoplanet acquired designation HD 137496 c. It was labeled as a chilly Jupiter, provided that its minimal mass was calculated to be about 7.66 Jupiter plenty and its equilibrium temperature is roughly 370 Ok. The planet orbits HD 137496 on a extremely (with an eccentricity of 0.477) each 480 days, separated by 1.21 AU from the star.

With an age of about 8.3 billion years, mass of 1.03 solar plenty and radius of roughly 1.59 solar radii, HD 137496 is characterised as a barely developed sun-like star. Its efficient temperature is 5,799 Ok, whereas its metallicity was discovered to be at a degree of -0.03.

In concluding remarks, the astronomers underlined the peculiarity of the newly detected planetary system. They famous that HD 137496 b is certainly one of only some well-characterized dense planets, what makes it an attention-grabbing goal for testing planet formation theories, density enhancing mechanisms, and likewise the presence of an prolonged comet-like mineral wealthy exosphere. Moreover, provided that HD 137496 c is a high-eccentricity planet, this method generally may very well be an attention-grabbing goal for planetary evolution research.


Astronomers discover twin sub-Neptune exoplanets orbiting nearby star


More info:
T. A. Silva et al, The HD 137496 system: A dense, sizzling super-Mercury and a chilly Jupiter. arXiv:2111.08764v1 [astro-ph.EP], arxiv.org/abs/2111.08764

© 2021 Science X Network

Citation:
Two exoplanets orbiting a sun-like star found (2021, November 26)
retrieved 26 November 2021
from https://phys.org/news/2021-11-exoplanets-orbiting-sun-like-star.html

This doc is topic to copyright. Apart from any truthful dealing for the aim of personal research or analysis, no
half could also be reproduced with out the written permission. The content material is supplied for info functions solely.





Source link

RELATED ARTICLES

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Most Popular

Recent Comments