Draft:ASASSN-24fw

  • Comment: That's why i completely overhauled the article Abdullah1099 (talk) 04:22, 6 March 2026 (UTC)
  • Comment: very interesting. this objetcs has been widely covered by the media. it would be great to some see some more secondary sources. Astropedian (talk) 12:35, 5 March 2026 (UTC)

ASASSN-24fw

Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Monoceros
Right ascension 07h 51m 41.996s[1]
Declination +09° 23′ 9.79″[1]
Characteristics
Evolutionary stage Main-sequence
Spectral type F8IV[2]
Astrometry
Radial velocity (Rv)36.87 [3] km/s
Proper motion (μ) RA: -3.75[3] mas/yr
Dec.: -7.612[3] mas/yr
Distance3,260[4] ly
Details[4][2]
Mass1.40+0.07
−0.11
 M
Radius1.95+0.05
−0.06
 R
Age2.75 ± 0.24 Gyr
Other designations
ASASSN-24fw, 2MASS J07051897+0612195, WISE J070518.97+061219.5, UCAC4 482-031200, Gaia DR3 3152916838954800512[3]
Database references
SIMBADdata

ASASSN-24fw is a F-type main-sequence star that underwent a rare, prolonged occultation event detected by the All Sky Automated Survey for SuperNovae (ASAS-SN), resulting in a deep dimming of approximately 4.1 magnitudes in the g-band lasting about 8–9 months from late September 2024 to late May or June 2025.[5][6]

Observation

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The star is located approximately 3,260 light-years away in the constellation of Monoceros. It has an estimated mass of about 1.4 M and exhibits an infrared excess indicative of circumstellar dust, with pre-event photometry showing stability over more than a decade of ASAS-SN monitoring.[4]

One model attributes the occultation to optically thick rings or a circumplanetary disk surrounding either a red dwarf or a substellar companion[7][8] (brown dwarf or massive gas giant, minimum mass around 3–3.4 MJ), with ring radius ~0.17 AU forming a large structure at ~14 AU orbital separation.[4][9]

The ASASSN-24fw planetary system[2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(years)
Eccentricity Inclination Radius
Ab (unconfirmed) 3.4 MJ 14.0 16060.0 0.88±0.07

See also

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References

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  1. ^ a b Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b c Martin, Pierre-Yves (2025). "Planet ASASSN-24fw Ab". exoplanet.eu. Retrieved 2026-03-06.
  3. ^ a b c d "UCAC4 482-031200". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2026-03-01.
  4. ^ a b c d Zakamska, Nadia L.; Pallathadka, Gautham Adamane; Bizyaev, Dmitry; Merc, Jaroslav; Owen, James E.; Reggiani, Henrique; Schlaufman, Kevin C.; Bąkowska, Karolina; Bednarz, Sławomir; Bernacki, Krzysztof; Gurgul, Agnieszka; Hall, Kirsten R.; Hambsch, Franz-Josef; Joachimczyk, Barbara; Kotysz, Krzysztof (2026-02-02). "ASASSN-24fw: Candidate Gas-rich Circumsecondary Disk Occultation of a Main-sequence Star". The Astronomical Journal. 171 (2): 95. arXiv:2507.05367. Bibcode:2026AJ....171...95Z. doi:10.3847/1538-3881/ae1fd9. ISSN 0004-6256.
  5. ^ Forés-Toribio, Raquel; JoHantgen, B.; Kochanek, C. S.; Jorstad, S. G.; Hermes, J. J.; Armstrong, J. D.; Ashall, C.; Burns, C. R.; Gaidos, E.; Hoogendam, W. B.; Hsiao, E. Y.; Medler, K.; Morrell, N.; Pfeffer, C.; Shappee, B. J. (2025-08-07). "ASASSN-24fw: An 8-month long, 4.1 mag, optically achromatic and polarized dimming event". The Open Journal of Astrophysics. 8: 114. arXiv:2507.03080. Bibcode:2025OJAp....8E.114F. doi:10.33232/001c.143105. ISSN 2565-6120.
  6. ^ Shah, Sarang; Marshall, Jonathan P; del Burgo, Carlos; Hajdu, Gergely; Rebollido, Isabel; Pilecki, Bogumił; Mahabal, Ashish; Zeegers, Sascha T; Reddy, Bacham Eswar; Kemper, Francisca; Kasliwal, Mansi M; Karambelkar, Viraj; Graham, Matthew J; Djorgovski, S G; Stern, Daniel (2026-02-03). "The nature of ASASSN-24fw's occultation: modelling the event as dimming by optically thick rings around a substellar companion". Monthly Notices of the Royal Astronomical Society. 546 (3) staf2251. doi:10.1093/mnras/staf2251. ISSN 0035-8711.
  7. ^ "Dusty structure explains near vanishing of faraway star | Department of Astronomy". astronomy.osu.edu. Retrieved 2026-03-06.
  8. ^ Tomaswick, Andy (2026-01-26). "Investigating the Star That Almost Vanished for Eight Months". Universe Today. Retrieved 2026-03-06.
  9. ^ Thompson, Mark (2026-02-15). "The Mystery of the Fading Star". Universe Today. Retrieved 2026-03-02.
[edit]
  • Anton Petrov (27 February 2026). The Star That Almost Vanished: The 97% Dimming Mystery. Video on YouTube.