V1400 Centauri
![]() A visual band light curve for V1400 Centauri, showing the 2007 eclipse. The main plot shows the SuperWASP data.[1] The inset plot, adapted from Mamajek et al.,[2] shows the data near mid-eclipse. The purple markers show the pairs of small brightness dips due to eclipses by rings. | |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Centaurus |
Right ascension | 14h 07m 47.92976s[3] |
Declination | −39° 45′ 42.7671″[3] |
Apparent magnitude (V) | 12.2 - ~15.6[4] |
Characteristics | |
Evolutionary stage | pre-main sequence[2] |
Spectral type | K5 IV(e) Li[2] |
Variable type | eclipsing[4]
|
Details | |
Myr | |
1SWASP J140747.93-394542.6[8] | |
Database references | |
SIMBAD | data |
V1400 Centauri (also known as 1SWASP J140747.93−394542.6, J1407 and Mamajek's Object) is a pre-main-sequence star in the constellation Centaurus at a distance of about 451 light-years from Earth.[6][9] A relatively young star, its age is estimated to be 16 million years, and its mass is about 90% that of the Sun.[2][10] The star has a maximum apparent magnitude of 12.2 and requires a telescope to be seen. The star's name comes from the SuperWASP (Wide Angle Search for Planets) program and the star's coordinates.
In 2007, J1407 was observed to be eclipsed and possibly orbited by at least one major body, 1SWASP J1407b[11] (shortened as J1407b). J1407b is thought to be either a large gas giant planet or a brown dwarf with an immense ring system.[2][6][12] Subsequent observations have not successfully detected J1407b, suggesting that it may be on a highly eccentric orbit around the star,[5] or that it is a rogue object that coincidentally transited V1400 Centauri.[13]
By 2021, it was discovered the parent star is strongly variable, with a 5.4-year long magnetic activity cycle, and no evidence was detected of additional planets or a repeat of the deep eclipses attributed to a transiting ring system.[14]
Variability
V1400 Centauri is the
The rotation of the V1400 Centauri every 3.2 days causes regular brightness changes with an amplitude of about 0.1 magnitudes. The star is also intrinsically variable, as is common for pre-main-sequence stars, with a slow decrease in brightness being shown over the periods 2001 to 2007 and 2012 to 2020. The 2007 eclipse was up to three magnitudes in depth.[14]
Suspected substellar companion
The discovery of the J1407 system and its unusual
J1407b is the first
J1407b has not been observed since its transit in 2007, suggesting that it may be on a highly
Alternatively, J1407b may also not be bound to J1407. The previous explanation involving J1407b orbiting J1407 would have J1407b as a brown dwarf companion with a large, Hill sphere filling ring system. However, issues with the stability of any rings combined with the lack of detection of another eclipse, suggests that J1407b may not be bound to J1407.[20] No other deep eclipses has been found in the data spanning from 1890 to 1990, nor in recent time-series photometry from 2012-2018. A significant proportion of orbital periods for J1407b from 5 to 20 years can be disregarded, therefore if there is an actual orbital period it is likely outside of this range.[20]
A search for J1407b with ALMA did not detect any bound companion, but did detect a point source consistent with an unbound object of 4-6 MJ. This may be the object which transited J1407 in 2007, or it may be a background galaxy or an artifact, which is considered less likely.[13]
From Earth's point of view, the ring system of J1407b would have an
Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b (unconfirmed) | 20.0±6.0 MJ | 3.9±1.7 | 3725±900 | >0.6 | — | — |
No additional transits from Jupiter-sized or larger planets were discovered in a 21-year long observational series by 2023.[14]
See also
Notes
- 1.arcseconds; 3.74 milliarcseconds) = 0.0000000296 ly; distance = 439 ly. 0.0000000296/439=0.0000000000674 of the sky; 0.00000000162 degrees; 0.000000097 arcminutes; 0.00000583 arcseconds; 0.00583 milliarcseconds
Saturn's main ring system diameter (D-F rings
References
- ^ "Search SuperWASP Time Series". NASA Exoplanet Archive. NASA. Archived from the original on 27 November 2022. Retrieved 27 November 2022.
- ^ S2CID 55818711.
- ^ S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ AAVSO. Archivedfrom the original on 2023-08-01. Retrieved 2023-08-01.
- ^ S2CID 118413749.
- ^ S2CID 56118870.
- .
- ^ "V* V1400 Cen". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 23 May 2024.
- ^ New York Times. Archivedfrom the original on May 20, 2018. Retrieved October 14, 2016.
- ^ a b "Eclipsing Ring System J1407". Cerro Tololo Inter-American Observatory. June 22, 2012. Archived from the original on July 12, 2017. Retrieved January 27, 2015.
- ^ a b "The Extrasolar Planet Encyclopaedia — 1SWASP J1407 b". Extrasolar Planets Encyclopaedia. 2014-10-29. Archived from the original on 2023-11-09. Retrieved 2017-06-01.
- ^ a b "Gigantic ring system around J1407b much larger, heavier than Saturn's". University of Rochester. January 26, 2015. Archived from the original on August 21, 2017. Retrieved January 27, 2015.
- ^ .
- ^ S2CID 235683556
- Bibcode:2015IBVS.6151....1K.
- Discovery News. Archived from the originalon March 11, 2016. Retrieved January 27, 2014.
- ^ Gigantic ring system around J1407b much larger, heavier than Saturn's Archived 2017-12-25 at the Wayback Machine, on University of Rochester website.
- ^ S2CID 119546405.
- CNN.com. Archivedfrom the original on 2020-11-08. Retrieved 2017-06-01.
- ^ S2CID 55015149.
- ^ Pluto Fact Sheet Archived 2018-05-09 at the Wayback Machine, NASA