Kepler-1625b I

Kepler-1625b I
Exomoon Kepler-1625b I orbiting exoplanet Kepler-1625b (artist concept).[1]
Discovery[2]
Discovered byAlex Teachey, David M. Kipping and Allan R. Schmitt
Discovery date2017
Primary transit
Orbital characteristics
Satellite ofKepler-1625b
Physical characteristics
0.437 RJ
Mass19.069 M🜨
0.06 MJ[3]
Mean density
0.95 g/cm3

Kepler-1625b I, a possible moon of exoplanet Kepler-1625b, may be the first exomoon ever discovered (pending confirmation), and was first indicated after preliminary observations by the Kepler Space Telescope.[4] A more thorough observing campaign by the Hubble Space Telescope took place in October 2017, ultimately leading to a discovery paper published in Science Advances in early October 2018. Studies related to the discovery of this moon suggest that the host exoplanet is up to several Jupiter masses in size, and the moon is thought to be approximately the mass of Neptune. Like several moons in the Solar System,[5] the large exomoon would theoretically be able to host its own moon, called a subsatellite, in a stable orbit, although no evidence for such a subsatellite has been found.[6]

Relative size and distance of Kepler-1625b and its moon Kepler-1625b-I, using images of Jupiter and Neptune
  1. ^ Chou, Felicia; Villard, Ray; Hawkes, Alison; Brown, Katherine (3 October 2018). "Astronomers Find First Evidence of Possible Moon Outside Our Solar System". NASA. Retrieved 5 October 2018.
  2. ^ Teachey, Alex; et al. (2018). "Evidence for a large exomoon orbiting Kepler-1625b". Science Advances. 4 (10): eaav1784. arXiv:1810.02362. Bibcode:2018SciA....4.1784T. doi:10.1126/sciadv.aav1784. PMC 6170104. PMID 30306135.
  3. ^ "The Extrasolar Planet Encyclopaedia — Kepler-1625 b I". Extrasolar Planets Encyclopaedia. Archived from the original on 5 October 2018. Retrieved 7 October 2018.
  4. ^ Teachey, A.; Kipping, D. M.; Schmitt, A. R. (26 July 2017). "HEK. VI. On the Dearth of Galilean Analogs in Kepler, and the Exomoon Candidate Kepler-1625b I". The Astronomical Journal. 155 (1) (published 22 December 2017): 36. arXiv:1707.08563. Bibcode:2018AJ....155...36T. doi:10.3847/1538-3881/aa93f2. S2CID 118911978.
  5. ^ Kollmeier, Juna A.; Raymond, Sean N. (21 November 2018). "Can moons have moons?". Monthly Notices of the Royal Astronomical Society: Letters. 483: L80–L84. arXiv:1810.03304. doi:10.1093/mnrasl/sly219.
  6. ^ Forgan, Duncan H. (11 February 2019). "The habitable zone for Earth-like exomoons orbiting Kepler-1625b". International Journal of Astrobiology. 18 (6): 510–517. arXiv:1810.02712. Bibcode:2019IJAsB..18..510F. doi:10.1017/s1473550418000514. ISSN 1473-5504. S2CID 118857039.