HD 20781 e

HD 20781 e
Discovery[1]
Discovered byMayor et al.
Discovery date2011, published in 2019[2]
Radial velocity[3]
Orbital characteristics[4]
0.3374+0.0155
−0.0170 AU
Eccentricity0.06+0.06
−0.04
85.5073+0.0983
−0.0947 d
2,455,513.3912+14.3623
−16.0090 JD
70.59°+61.40°
−67.58°
Semi-amplitude2.60±0.14 m/s
StarHD 20781
Physical characteristics
~2.17 R🜨 (estimate)[2]
Mass≥14.03±1.56 M🜨[4]

HD 20781 e is a hot Neptune around the star HD 20781. The planet has a minimum mass of 14.03 Earth masses[4] and it orbits with a semi-major axis of 0.3374 astronomical units and an orbital eccentricity of approximately 0.06.[2][4] With the same composition as Neptune, it would have a radius of 3.79 times that of the Earth. With the same composition as Earth, it would have a radius of 2.08 times that of the Earth. It orbits near the inner edge of the habitable zone of HD 20781.[citation needed]

This planet was initially reported in a 2011 preprint, which referred to it as HD 20781 c.[1] However, the 2017 paper (published in a journal in 2019) that confirmed the planet designated it HD 20781 e, using the c designation for a different, shorter-period planet.[4]

  1. ^ a b Cite error: The named reference Mayor2011 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference nasaref was invoked but never defined (see the help page).
  3. ^ "Planet HD 20781 e". Extrasolar Planets Encyclopaedia. Retrieved 2 January 2016.
  4. ^ a b c d e Cite error: The named reference Udry2019 was invoked but never defined (see the help page).