| YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets | |
|
|
Author | Message |
---|
Sirius_Alpha Admin
Number of posts : 4319 Location : Earth Registration date : 2008-04-06
| Subject: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets 13th August 2017, 8:24 pm | |
| The HARPS search for southern extra-solar planets XLII. A system of Earth-mass planets around the nearby M dwarf YZ Cet https://arxiv.org/abs/1708.03336 - Quote :
- Exoplanet surveys have shown that systems with multiple low-mass planets on compact orbits are common. Except for few cases, however, the masses of these planets are generally unknown. At the very end of the main sequence, host stars have the lowest mass and hence offer the largest reflect motion for a given planet. In that context, we monitored the low-mass (0.13Msun) M dwarf YZ Cet (GJ 54.1, HIP 5643) intensively and obtained both radial velocities and stellar-activity indicators derived from both spectroscopy and photometry. We find strong evidence that it is orbited by at least three planets in compact orbits (P=1.97, 3.06, 4.66 days), with the inner two near a 2:3 mean-motion resonance. The minimum masses are comparable to that of Earth (Msini=0.75+-0.13, 0.98+-0.14, and 1.14+-0.17 Mearth) and also the lowest masses measured by radial velocity so far. We note the possibility for an even lower-mass, fourth planet with Msini=0.472+-0.096 Mearth at P=1.04 days. An n-body dynamical model is used to put further constraints on the system parameters. At 3.6 parsecs, YZ Cet is the nearest multi-planet system detected to date.
_________________ Caps Lock: Cruise control for 'Cool'!
| |
|
| |
tommi59 Jovian
Number of posts : 593 Age : 46 Location : Baile Atha Cliath Registration date : 2010-07-31
| Subject: Re: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets 14th August 2017, 3:04 am | |
| Nice good chances to detect transits especially for unconfirmed candidate. | |
|
| |
Edasich dK star
Number of posts : 2267 Location : Tau Ceti g - Mid Latitudes Registration date : 2008-06-02
| Subject: Re: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets 14th August 2017, 4:29 am | |
| Great find. More exoplanets in the Solar Neighborhood. | |
|
| |
Sirius_Alpha Admin
Number of posts : 4319 Location : Earth Registration date : 2008-04-06
| Subject: Re: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets 31st August 2017, 6:57 pm | |
| _________________ Caps Lock: Cruise control for 'Cool'!
| |
|
| |
Sirius_Alpha Admin
Number of posts : 4319 Location : Earth Registration date : 2008-04-06
| Subject: Re: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets 22nd August 2018, 8:42 pm | |
| Aliasing in the Radial Velocities of YZ Ceti: An Ultra-Short Period for YZ Ceti c? https://arxiv.org/abs/1808.07059 - Quote :
- Mid-late M stars are opportunistic targets for the study of low-mass exoplanets in transit because of the high planet-to-star radius ratios of their planets. Recent studies of such stars have shown that, like their early-M counterparts, they often host multi-resonant networks of small planets. Here, we reanalyze radial velocity measurements of YZ Ceti, an active M4 dwarf for which the HARPS exoplanet survey recently discovered three exoplanets on short-period (P = 4.66, 3.06, 1.97 days) orbits. Our analysis finds that the orbital periods of the inner two planets cannot be uniquely determined using the published HARPS velocities. In particular, it appears likely that the 3.06-day period of YZ Ceti c is an alias, and that its true period is 0.75 days. If so, the revised minimum mass of this planet is less than 0.6 Earth masses, and its geometric transit probability increases to 10%. We encourage additional observations to determine the true periods of YZ Ceti b and c, and suggest a search for transits at the 0.75-day period in TESS lightcurves.
_________________ Caps Lock: Cruise control for 'Cool'!
| |
|
| |
Sirius_Alpha Admin
Number of posts : 4319 Location : Earth Registration date : 2008-04-06
| Subject: Re: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets 5th February 2020, 11:59 pm | |
| Another update to the system. No fourth planet, better constraints on the three that are there. No transit detection of the b planet with TESS. The CARMENES search for exoplanets around M dwarfs. Characterization of the nearby ultra-compact multiplanetary system YZ Ceti https://arxiv.org/abs/2002.01772 _________________ Caps Lock: Cruise control for 'Cool'!
| |
|
| |
Sirius_Alpha Admin
Number of posts : 4319 Location : Earth Registration date : 2008-04-06
| Subject: Re: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets 3rd April 2023, 12:03 pm | |
| Possible magnetic star-planet interaction. Coherent radio bursts from known M-dwarf planet-host YZ Ceti https://www.nature.com/articles/s41550-023-01914-0?utm_campaign=natastronTWT - Conclusions wrote:
- Using simple Poisson statistics, the probability of seeing at least one event in the 3.6 h associated with epoch 5 is ~24%. By contrast, the probability of seeing one burst, on two separate occasions within 2 h of a given phase (a 4 h window) is only 5.1%—small but insufficient as conclusive evidence. It is thus plausible that the bursts could have no association with the planetary system and be a normal part of the radio stellar activity of slowly rotating M dwarfs, which is not yet well studied. The mechanisms powering the emission remain inconclusive, and we thus categorize YZ Cet as an SPI candidate, requiring further follow-up to discern the nature of the radio bursts.
_________________ Caps Lock: Cruise control for 'Cool'!
| |
|
| |
Sponsored content
| Subject: Re: YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets | |
| |
|
| |
| YZ Cet - Very nearby (3.6 pc) M dwarf with Earth-mass planets | |
|