Astronomy:SPECULOOS-3

From HandWiki

SPECULOOS-3, also known as LSPM J2049+3336, is a red dwarf star (spectral type M6.5) located 54.6 light-years from Earth[1] in the constellation Cygnus. It is one of the smallest known stars, and is much cooler, dimmer and smaller than the Sun, having 0.1 times the mass, 0.08% the Sun's luminosity, and an effective temperature of 2,800 K (2,530 °C), which is less than half of the Sun's temperature (5,772 K).[1] It is orbited by one known exoplanet, and is the second ultra-cool dwarf discovered to have a planetary system, after TRAPPIST-1.[2][3]

Stellar properties

The age of SPECULOOS-3 is constrained at 6.6 billion years, 44% older than the Solar System, with significant margins of error. A bayesian analysis of the star derived a mass of 0.101 M☉, an effective temperature of 2,800 K (2,530 °C; 4,580 °F) and a luminosity of 8.35×10−6 L☉. These characteristics classify SPECULOOS-3 as an ultracool dwarf, which are stars at the end of the main sequence, with low temperatures, low luminosites and sizes similar to Jupiter. It is spinning at a rotational velocity of 4.8 km/s and has a projected rotational period of 1.34 days.[1]

The stellar radius, computed using the Stefan–Boltzmann law, is 0.134 R☉ (93,000 kilometres).[1] This makes SPECULOOS-3 the second-smallest star known to host a transiting planet, just marginally larger than TRAPPIST-1,[1] and its size is similar to that of Jupiter.[4] Its apparent magnitude is estimated at 17.8,[5] which is too faint to be seen by the naked eye.

It was first discovered in 2005 as part of the LSPM-North catalog, whose objective was to map stars in the northern celestial hemisphere with proper motions larger than 0.15" per year and apparent magnitudes smaller than 21m.[5] Its trignometric parallax was first measured in 2014 at 67.5±1.7 mas, translating into a distance of 14.8 parsecs (48.27 ly).[6] Gaia Data Release 3 (2023) published a parallax of 59.7 milliarcseconds, translating into a distance of 16.75 parsecs (54.6 ly).[7] This make this star relatively close to Earth.[8]

Red dwarf stars such as SPECULOOS-3 are the most numerous type of stars, making up 70% of all stars in the Milky Way galaxy. They are expected to live 10 times more than the Sun, with lifespans longer than 100 billion years.[8]

Planetary system

See also: Astronomy:SPECULOOS-3 b

SPECULOOS-3 hosts one exoplanet, discovered in 2024 via the transit method.[9] Named SPECULOOS-3 b, it is an Earth-sized exoplanet that has a radius similar to that of Earth, equivalent to 0.98 Earth radii.[1] It takes only about 17 hours to complete an orbit around SPECULOOS-3, and, because of that proximity, it receives very high levels of radiation and is likely tidally locked, meaning that one side of the planet always faces its host star.[4] Its discovery was made using the SPECULOOS project, and was announced on 15 May 2024 in the academic journal Nature Astronomy.[10]

The mass of SPECULOOS-3 b has been not measured,[1] but it has been estimated by NASA's Eyes on Exoplanets at 0.894 M⊕.[11] Its equilibrium temperature is about 553 K (280 °C; 536 °F), meaning that its dayside is likely formed by solid rock.[1] The planet is an optimal target for characterization with the James Webb Space Telescope, giving more information about the planet's mineralogy[10] and the possibility of hosting an atmosphere.[12]

The SPECULOOS-3 planetary system[1]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
b — 0.007330(55) 0.71912603(57) — 89.44±0.39° 0.977±0.022 R⊕

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Gillon, Michaël; Pedersen, Peter P.; Rackham, Benjamin V.; Dransfield, Georgina; Ducrot, Elsa; Barkaoui, Khalid; Burdanov, Artem Y.; Schroffenegger, Urs et al. (2024-05-15). "Detection of an Earth-sized exoplanet orbiting the nearby ultracool dwarf star SPECULOOS-3" (in en). Nature Astronomy 8 (7): 865–878. doi:10.1038/s41550-024-02271-2. ISSN 2397-3366. Bibcode: 2024NatAs...8..865G. https://rdcu.be/dH0aN. 
  2. ↑ Anderson, Natali (2024-05-15). "Earth-Sized Exoplanet Found Orbiting Nearby Ultracool Red Dwarf" (in en-US). https://www.sci.news/astronomy/earth-sized-exoplanet-ultracool-red-dwarf-12934.html. 
  3. ↑ "Detection of an Earth-sized exoplanet orbiting the ultracool dwarf star SPECULOOS-3" (in en). https://www.sciencedaily.com/releases/2024/05/240515122831.htm. 
  4. ↑ 4.0 4.1 Hill, Samantha (2024-05-16). "Found: An Earth-sized exoplanet named SPECULOOS-3 b" (in en-US). https://www.astronomy.com/science/found-an-earth-sized-exoplanet-named-speculoos-3-b/. 
  5. ↑ 5.0 5.1 Lépine, Sébastien; Shara, Michael M. (2005-03-01). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)". The Astronomical Journal 129 (3): 1483–1522. doi:10.1086/427854. ISSN 0004-6256. Bibcode: 2005AJ....129.1483L. https://ui.adsabs.harvard.edu/abs/2005AJ....129.1483L.  SPECULOOS-3's database entry at VizieR.
  6. ↑ Dittmann, Jason A.; Irwin, Jonathan M.; Charbonneau, David; Berta-Thompson, Zachory K. (2014-04-01). "Trigonometric Parallaxes for 1507 Nearby Mid-to-late M Dwarfs". The Astrophysical Journal 784 (2): 156. doi:10.1088/0004-637X/784/2/156. ISSN 0004-637X. Bibcode: 2014ApJ...784..156D. https://ui.adsabs.harvard.edu/abs/2014ApJ...784..156D.  SPECULOOS-3's database entry at VizieR.
  7. ↑ Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  8. ↑ 8.0 8.1 "Discovery Alert: An Earth-sized World and Its Ultra-cool Star - NASA Science" (in en-US). https://science.nasa.gov/universe/exoplanets/discovery-alert-an-earth-sized-world-and-its-ultra-cool-star/. 
  9. ↑ Template:Cite EPE
  10. ↑ 10.0 10.1 "Astronomers discover new Earth-sized world orbiting an ultra-cool star" (in en). May 15, 2024. https://phys.org/news/2024-05-astronomers-earth-sized-world-orbiting.html. 
  11. ↑ "SPECULOOS-3 b - NASA Science" (in en-US). https://science.nasa.gov/exoplanet-catalog/speculoos-3-b/. 
  12. ↑ Lea, Robert (2024-05-15). "Earth-size planet discovered around cool red dwarf star shares its name with a biscuit" (in en). https://www.space.com/earth-size-planet-speculoos-3b. 

Cite error: <ref> tag with name "SIMBAD" defined in <references> is not used in prior text.

Cite error: <ref> tag with name "constellation" defined in <references> is not used in prior text.



Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:SPECULOOS-3&oldid=4134310"