Gliese 357 d is an exoplanet, considered to be a "Super-Earth" within the circumstellar habitable zone of its parent star.[3][4][5][6] The planet orbits Gliese 357, 31 light-years from the Solar System,[4] The system is part of the Hydra constellation.[4]
 | |
| Discovery | |
|---|---|
| Discovered by | Rafael Luque, Diana Kossakowski |
| Discovery site | TESS |
| Discovery date | 2019 |
| Radial velocity | |
| Orbital characteristics | |
| 0.204±0.015 AU[1] | |
| Eccentricity | ≈0.033 ± 0.057[2] |
| 55.70±0.05 d[1] | |
| Inclination | <40°[2] |
| Star | Gliese 357 |
| Physical characteristics | |
| Mass | 6.1±1.0 M🜨[1] 7.20±1.07 M🜨[2] |
| Temperature | 219.6 ± 5.9 K (−53.55 ± 5.90 °C; −64.39 ± 10.62 °F)[1] |
The planet was discovered by the TESS team and announced in July 2019. The data confirming the presence of the planet was uncovered in ground-based observation dating back to 1998 while confirming the TESS detection of Gliese 357 b, a “hot earth” that orbits much closer to the parent star.[6] Even though Gliese 357 d is 20% closer to Gliese 357 than Earth is to the Sun, Gliese 357 is much smaller than the Sun. So it receives as much energy as Mars. As a result, it is estimated that the average temperature is -64°F (-53°C), but this temperature is survivable for humans; if there is a thick enough atmosphere, the actual temperature could be much higher. If humans traveled there using modern spacecraft, it would take them about 660,000 years to get there.[a] The planet is 6.1 times more massive than Earth and 2.3 times Earth's size.[8]
Footnotes
edit- ^ Calculated assuming the spacecraft travels at 14 km/s. For comparison, the New Horizons spacecraft is exiting the solar system at a velocity of 13.7 km/s as of June 2024.[7]
References
edit- ^ a b c d Luque, R.; Pallé, E.; et al. (2019). "Planetary system around the nearby M dwarf GJ 357 including a transiting, hot, Earth-sized planet optimal for atmospheric characterization". Astronomy & Astrophysics. 628: A39. arXiv:1904.12818. Bibcode:2019A&A...628A..39L. doi:10.1051/0004-6361/201935801. ISSN 0004-6361. Archived from the original on 2023-09-24. Retrieved 2020-05-12.
- ^ a b c Jenkins, J S; Pozuelos, F J; et al. (2019). "GJ 357: a low-mass planetary system uncovered by precision radial velocities and dynamical simulations". Monthly Notices of the Royal Astronomical Society. 490 (4): 5585–5595. arXiv:1909.00831. doi:10.1093/mnras/stz2937. ISSN 0035-8711.
- ^ Falconer, Rebecca (2019-08-01). "Newly uncovered super-Earth 31 light-years away may be habitable". Axios. Archived from the original on 2019-12-18. Retrieved 2019-08-04.
- ^ a b c Reddy, Francis; Center, NASA’s Goddard Space Flight (2019-07-31). "TESS Discovers Habitable Zone Planet in GJ 357 System". SciTechDaily. Archived from the original on 2019-08-01. Retrieved 2019-08-01.
- ^ "Potentially habitable 'super-Earth' discovered just 31 light-years away". NBC News. 31 July 2019. Archived from the original on 2019-07-31. Retrieved 2019-08-01.
- ^ a b Garner, Rob (2019-07-30). "NASA's TESS Helps Find Intriguing New World". NASA. Archived from the original on 2019-08-01. Retrieved 2019-08-01.
- ^ Talbert, Tricia (2021-04-15). "NASA's New Horizons Reaches a Rare Space Milestone". NASA. Archived from the original on August 22, 2022. Retrieved 2021-04-18.
- ^ "plot_GJ_357.png". Planetary Habitability Laboratory. 2019-09-03.
