Comments on: Astronomers detect exoplanet half as massive as the Earth around second closest star system https://behindtheblack.com/behind-the-black/points-of-information/astronomers-detect-exoplanet-half-as-massive-as-the-earth-around-second-closest-star-system/ Wed, 02 Oct 2024 13:57:49 +0000 hourly 1 https://wordpress.org/?v=6.9.4 By: Madrocketsci https://behindtheblack.com/behind-the-black/points-of-information/astronomers-detect-exoplanet-half-as-massive-as-the-earth-around-second-closest-star-system/#comment-1523743 Wed, 02 Oct 2024 13:57:49 +0000 https://behindtheblack.com/?p=108794#comment-1523743 Different methods sensitive to different things.

Direct observation: far far orbiting super jovian planets like fomalhaut b

Gravitational interactions: close orbiting super jovian

Transit method: Close orbiting smaller planets

Frustratingly, earth is sort of in between the range of all these methods. Might be able to pick up with transit method, but would require a long observation time, and the ecliptic plane to just happen to lie on line of sight

]]> By: sippin_bourbon https://behindtheblack.com/behind-the-black/points-of-information/astronomers-detect-exoplanet-half-as-massive-as-the-earth-around-second-closest-star-system/#comment-1523660 Wed, 02 Oct 2024 04:55:39 +0000 https://behindtheblack.com/?p=108794#comment-1523660 The first confirmed exoplanet was was announced 29 years ago, next week.
In my mind, that would explain why most discoveries are shorter orbital periods. It can take years of data to find these things.

The smallesr exoplanet found to dat is 2x the size if the Moon, orbiting a pulsar 2300 LY away.

]]> By: sippin_bourbon https://behindtheblack.com/behind-the-black/points-of-information/astronomers-detect-exoplanet-half-as-massive-as-the-earth-around-second-closest-star-system/#comment-1523656 Wed, 02 Oct 2024 04:43:30 +0000 https://behindtheblack.com/?p=108794#comment-1523656 Mr Eastman,
HD 118203c found this year.
It is further than Jupiter from its star, at 6.2 AU, taking over 13.9 years to orbit.
Estimated radius 1.11 compared to Jupiter, but much higher density, with a mass estimated at 11.1 Jupiters.

Found using the radial velocity method (Doppler shift).

The star is in the Ursa Major constellation, approximately 300 LY distant. G0 V star, so a little hotter than Sol, and in the main sequence. Not visible to the naked eye.

]]> By: David Eastman https://behindtheblack.com/behind-the-black/points-of-information/astronomers-detect-exoplanet-half-as-massive-as-the-earth-around-second-closest-star-system/#comment-1523555 Tue, 01 Oct 2024 19:27:12 +0000 https://behindtheblack.com/?p=108794#comment-1523555 I once heard, but haven’t seen the math confirmed, that the techniques we are currently using to detect exoplanets are not sufficiently high resolution to detect our own solar system if we were observing from 20 light years or so away. We’re mostly finding planets that orbit very close to their stars with periods measured in days, because even something like Jupiter doesn’t perturb the sun enough for our current techniques to notice, it’s simply too far out and thus moving slowly enough that we’d have to observe a star very precisely for decades to notice.

]]>