Ross 128

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Star
Ross 128
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation Virgin
Right ascension 11 h 47 m 44.4 s
declination + 00 ° 48 ′ 16.4 ″
Apparent brightness 11.15 likes
Typing
Known exoplanets 1
B − V color index +1.75 
U − B color index +1.32 
R − I index +1.68 
Spectral class M4.5V
Variable star type UV 
Astrometry
Radial velocity (−31.17 ± 0.09) km / s
parallax (296.31 ± 0.07)  mas
distance (11.00 ± 0.01)  ly
(3.37 ± 0.01)  pc
Visual absolute brightness M vis +13.49 mag
Proper movement 
Rec. Share: (+607.68 ± 0.14)  mas / a
Dec. portion: (−1223.32 ± 0.08)  mas / a
Physical Properties
Dimensions (0.178 ± 0.004)  M ☉
radius (0.210 ± 0.006)  R ☉
Luminosity

(0.0036 ± 0.0004)  L ☉

Effective temperature (3192 ± 60)  K.
Metallicity [Fe / H] (−0.02 ± 0.08)
Age 5 billion  a
Other names
and catalog entries
Gliese catalog FY 447 [1]
Hipparcos catalog HIP 57548 [2]
Tycho catalog TYC 272-1051-1 [3]
2MASS catalog 2MASS J11474440 + 0048164 [4]
Other names Ross 128 • FI Virginis • ASCC 1136005 • USNO-B1.0 0908-00204201

Ross 128 is a red dwarf star about 3.4  pc (10.9  light years ) from our solar system. Its closest neighbor is Wolf 359 , which is about 1.2 pc (3.8 light years) away. Ross 128 can be found near the ecliptic , near the constellation Virgo, and is one of the UV Ceti stars .

Planetary system

In September 2017, a team of scientists reported on the planet Ross 128 b . It orbits the star at a distance of about 0.05  AU with an orbital period of 9.9 days. It is unclear whether the planet is inside or outside the habitable zone . Assuming that its albedo is in the range of the planets of the solar system , its equilibrium temperature is estimated to be around −60 to +20 ° C. The planet has a weak magnetic field , which could make an atmosphere possible. These data are based on an evaluation of recordings by the High Accuracy Radial Velocity Planet Searcher (HARPS) from 2005 to 2016.

After Proxima Centauri b , it is the second closest known planet outside the solar system, on which the conditions for earth-like life could be given.

Unusual radio signals

On May 12, 2017, unusual broadband radio signals were received from the direction of Ross 128b at the Arecibo Observatory in Puerto Rico . It was an approximately periodic signal with decreasing frequency. However , this observation could not be repeated during further observations in Arecibo such as at the Green Bank Telescope and the Allen Telescope Array . This suggests that the puzzling signal may have come from a satellite in orbit.

See also

Web links

Commons : Ross 128  - collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d e f g h Ross 128. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed November 6, 2018 .
  2. ↑ a b FI Vir. In: VSX. AAVSO, accessed November 6, 2018 .
  3. ↑ calculated from apparent brightness and distance
  4. ↑ a b P. E. Kervella, F. Arenou, F. Mignard, F. Thévenin: Stellar and substellar companions of nearby stars from Gaia DR2. Binarity from proper motion anomaly . In: Astronomy & Astrophysics . 623, p. A72. arxiv : 1811.08902 . bibcode : 2019A & A ... 623A..72K . doi : 10.1051 / 0004-6361 / 201834371 .
  5. ^ Ross 128. In: NASA Exoplanet Archive . Retrieved November 6, 2018 .
  6. ↑ a b c Ross 128 b. In: Extrasolar Planets Encyclopaedia . Retrieved November 6, 2018 .
  7. ↑ a b X. Bonfils, N. Astudillo-Defru, R. Diaz, J.-M. Almenara, T. Forveille, F. Bouchy, X. Delfosse, C. Lovis, M.Mayor, F. Murgas, F. Pepe, NC Santos, D. Segransan, S. Udry, A. Wunsche: A temperate exo-Earth around a quiet M dwarf at 3.4 parsecs , Astronomy and Astrophysics .
  8. ↑ Closest planet with moderate climate discovered around calm star, ESA press release , November 15, 2017.
  9. ↑ Abel Mendez: Strange Signals from the Nearby Red Dwarf Star Ross 128 . In: Planetary Habitability Laboratory at University of Puerto Rico at Arecibo . July 12, 2017. Retrieved July 17, 2017.
  10. ↑ Abel Mendez: Strange Signals from the Nearby Red Dwarf Star Ross 128 . In: Planetary Habitability Laboratory at University of Puerto Rico at Arecibo . July 17, 2017. Archived from the original on July 17, 2017. Retrieved July 17, 2017.
  11. ↑ Strange signals from Ross 128 - contact? , Heise.de, May 15, 2017, accessed July 15, 2017.
  12. ↑ Abel Méndez, Jorge Zuluaga: The Weird! Signal . In: University of Puerto Rico at Arecibo . July 21, 2017. Retrieved July 22, 2017.
  13. Jump up ↑ JE Enriquez, A. Siemion, R. Dana, S. Croft, A. Méndez, A. Xu, D. DeBoer, V. Gajjar, G. Hellbourg, H. Isaacson, M. Lebofsky, DHE MacMahon, DC Price, D. Werthimer, J. Zuluaga: Breakthrough Listen Follow-up of the Reported Transient Signal Observed at the Arecibo Telescope in the Direction of Ross 128 , October 23, 2017.
  14. ↑ Mike Wall: Not Aliens: Weird Radio Signal from Star Likely Has Duller Explanation . In: Space.com . July 21, 2017. Retrieved July 22, 2017.