Misplaced Pages

VVV-WIT-07

Article snapshot taken from[REDACTED] with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
(Redirected from VVV WIT 07) Star noted for unusual dimming events

VVV-WIT-07

Context star field of
VVV-WIT-07
Observation data
Epoch J2000      Equinox J2000
Constellation Scorpius
Right ascension 17 26 29.387
Declination −35° 40′ 56.20″
Astrometry
Proper motion (μ) RA: 2.469 mas/yr
Dec.: 1.374 mas/yr
Parallax (π)2.5190 ± 1.1187 mas
Distanceapprox. 1,300 ly
(approx. 400 pc)
Other designations
Gaia DR2 5974962995291907584
Database references
SIMBADdata

VVV-WIT-07 is a unique variable star which presents a sequence of recurrent dimmings (Ks~14.35 – 16.164) with a possible deep eclipse in July 2012. The star, located in the Scorpius constellation about 23,000 ly (7,100 pc) away, is not a binary star, which would eliminate such a system from explaining the various observed dimmings.

Overview

A light curve for VVV-WIT-07, adapted from Saito et al. (2019). The inset plot shows the July 2012 dimming event with an expanded scale.

The star was found by the "Vista Variables in the Via Lactea" (VVV) project, which is a survey of European Southern Observatory (ESO) variability of the innermost bulge of the Milky Way galaxy. The near-infrared spectra of VVV-WIT-07 appear without features, without prominent emission or absorption lines. The characteristics found in the light curve of VVV-WIT-07 (WIT refers to "What Is This?") are similar to those seen in J1407 (Mamajek's Object), a pre-MS K5 dwarf with a ring system that eclipses the star or, alternatively, to Tabby's star, an F3 IV/V star that shows irregular and aperiodic obscurations in its light curve.

From 2010 to 2018, the star dimmed and brightened irregularly (v~14.35 – 16.164), and seemed similar to Tabby's star, except the light from VVV-WIT-07 dimmed by up to 80 percent, while Tabby's star faded by only about 20 percent. Another star, J1407, however, has been found to have dimmed by up to 95%, which may be more similar to the light curve presented by VVV-WIT-07. Nonetheless, according to ESO astronomer Valentin Ivanov, "A key word that could be used to describe our finding is extreme. In every aspect ... We have identified a system that challenges the imagination even more than usual, because it is so unlike our own planetary system."

See also

References

  1. ^ Saito, Roberto K.; et al. (2019). "VVV-WIT-07: another Boyajian's star or a Mamajek's object?". Monthly Notices of the Royal Astronomical Society. 482 (4): 5000–5006. arXiv:1811.02265. Bibcode:2019MNRAS.482.5000S. doi:10.1093/mnras/sty3004. S2CID 119068259.
  2. Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  3. ^ Ivanov, Valentin D. (22 March 2019). "What Is This? - Astronomers discover mysterious star displaying never-seen-before behaviour". European Southern Observatory. Retrieved 9 June 2019.
  4. Saito, R.K.; et al. (6 November 2018). "VVV-WIT-07: another Boyajian's star or a Mamajek's object?". Monthly Notices of the Royal Astronomical Society. 482 (4): 5000–5006. arXiv:1811.02265. Bibcode:2019MNRAS.482.5000S. doi:10.1093/mnras/sty3004. S2CID 119068259.
  5. Seidel, Jamie (23 November 2018). "VVV-WIT-07: This ancient, erratic star hides a dark secret". The Advertiser. Retrieved 8 June 2019.
  6. Anderson, Paul Scott (29 November 2018). "Have astronomers found another Tabby's Star? - Remember when astronomers found Tabby's Star and said they'd never seen anything like it? Now there's another one … maybe". Earth & Sky. Retrieved 8 June 2019.
  7. Redd, Nola Taylor (21 November 2018). "Have Astronomers Found Another "Alien Megastructure" Star? - Scientists now have a second example of a strange stellar phenomenon speculatively linked to extraterrestrial intelligence in 2015". Scientific American. Retrieved 8 June 2019.
  8. ^ Grossman, Lisa (22 December 2018). "Astronomers spot another star that flickers like Tabby's star - It's unclear what's causing the newly discovered object to blink, but it's probably not aliens". Science News. Vol. 194, no. 12. p. 9. Retrieved 8 June 2019.

External links

Constellation of Scorpius
Stars
Bayer
Flamsteed
Variable
HR
HD
Other
Exoplanets
Star
clusters
NGC
Other
Nebulae
NGC
Galaxies
NGC
Other
Category
Extraterrestrial life
Events and objects
Signals of interest
Misidentified
Stars
Other
Life in the Universe
Planetary
habitability
Space missions
Interstellar
communication
Types of alleged
extraterrestrial beings
Hypotheses
Fermi paradox solutions
Related topics
Portals: Categories:
VVV-WIT-07 Add topic