U Scorpii

Recurrent nova system first seen in 1863

Not to be confused with Upsilon Scorpii.

U Scorpii

Location of U Scorpii (circled in red)

Observation data
Epoch J2000      Equinox J2000
Constellation | Scorpius
Right ascension | 16h 22m 30.78s[1]
Declination | −17° 52′ 42.8″[1]
Apparent magnitude (V) | 7.5 Max.
17.6 Min.[2]
Characteristics
Spectral type | ? / White Dwarf
Variable type | Recurrent nova[2]
Astrometry
Radial velocity (Rv)| 65[3] km/s
Proper motion (μ)|  RA: −0.380±0.202[4] mas/yr
Dec.: −7.591±0.144[4] mas/yr
Parallax (π)| −0.0945±0.1334 mas[4]
Distance| 19600+21000
−5300[2] pc
Other designations
AAVSO 1616-17, Nova Sco 1863, BD−17 4554, Gaia DR2 6246188565119443072, 2MASS J16223079-1752431[3]
Database references
SIMBAD| data

U Scorpii (U Sco) is a recurrent nova system, one of 10 known recurring novae in the Milky Way galaxy.[5] Located near the northern edge of the constellation Scorpius it normally has a magnitude of 18, but reaches a magnitude of about 8 during outbursts. Outbursts have been observed in 1863, 1906, 1936, 1979, 1987, 1999,[6] 2010,[7] and 2022.

The 2010 outburst was predicted to occur April 2009 ± 1.0 year, based on observations during quiescence following the 1999 outburst.[8] The U Sco 2010 eruption faded by 1 magnitude in 1 day, and by 4 magnitudes in 6 days. By February 6 it was dimmer than magnitude 13. Between February 10–19, it was flickering around magnitude 14. The eruption ended on day 64, which is the fastest observed decline to quiescence of a recurring nova.[9] This eruption of U Sco became the best-observed nova event to its day, with 22,000 magnitudes accumulated.[9] Astronomers then predicted that another eruption of U Sco would occur in 2020±2. This prediction was correct: it brightened to +7.8 magnitude on 6 June 2022.[citation needed]

AAVSO light curve of recurrent nova U Sco from 1 Jan 2010 to 1 Sept 2010. Up is brighter and down is fainter. Day numbers are Julian day. Different colors reflect different bandpasses.

Originally identified as a nova in 1863 by English astronomer N.R. Pogson, U Scorpii was the third nova to be identified as recurrent, by American astronomer and historian of science Helen L. Thomas, in the years preceding World War II.[10][11]

## References

[edit]

1. ^ a b Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
2. ^ a b c Schaefer, Bradley E. (2018). "The distances to Novae as seen by Gaia". Monthly Notices of the Royal Astronomical Society. 481 (3): 3033–3051\. arXiv:1809.00180. Bibcode:2018MNRAS.481.3033S. doi:10.1093/mnras/sty2388. S2CID 118925493.
3. ^ a b "U Scorpii". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-08-17.
4. ^ a b c 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.
5. ^ Comprehensive Photometric Histories of All Known Galactic Recurrent Novae, B. Schaefer
6. ^ The 1999 Outburst of the Recurrent Nova U Scorpii, Anupama & Dewangan
7. ^ Thar She Blows! U Scorpii Erupts as Predicted, A. MacRobert
8. ^ B. Schaefer; A. Pagnotta; et al. (October 2010). "Discovery of the 2010 Eruption and the Pre-Eruption Light Curve for Recurrent Nova U Scorpii". The Astronomical Journal. 140 (4): 925–932\. arXiv:1004.2842. Bibcode:2010AJ....140..925S. doi:10.1088/0004-6256/140/4/925. S2CID 118394042. Retrieved 12 February 2015.
9. ^ a b Matthew Templeton (May 6, 2010). "Long-term monitoring of the recurrent nova U Scorpii". AAVSO. Retrieved 2010-11-15.
10. ^ Templeton, Matthew. "U Scorpii | aavso". www.aavso.org. Retrieved 2022-05-28.
11. ^ "Eloge: Helen Meriwether Lewis Thomas, 21 August 1905-6 August 1997". Isis. 89 (2): 316–317\. 1998-06-01. doi:10.1086/384004. ISSN 0021-1753. S2CID 144636725.

## External links

[edit]

* http://www.phys.lsu.edu/dept/people/schaefer.html Archived 2009-03-13 at the Wayback Machine
* U Scorpii in Outburst
* Long-term monitoring of the recurrent nova U Scorpii (AAVSO 2010 April 9)
* AAVSO: Quick Look View of AAVSO Observations (get recent magnitude estimates for U Sco)

* v
* t
* e

Constellation of Scorpius

* List of stars in Scorpius
* Scorpius in Chinese astronomy

Stars|

| Bayer|

* α (Antares)
* β (Acrab)
* δ (Dschubba)
* ε (Larawag)
* ζ1
* ζ2
* η
* θ (Sargas)
* ι1
* ι2
* κ (Girtab)
* λ (Shaula)
* μ1 (Xamidimura)
* μ2 (Pipirima)
* ν (Jabbah)
* ξ
* ο
* π (Fang)
* ρ (Iklil)
* σ (Alniyat)
* τ (Paikauhale)
* υ (Lesath)
* χ
* ψ
* ω1
* ω2
* G (Fuyue)
* H (β Nor)
* N (α Nor)
* Q

|

Flamsteed|

* 1 (b)
* 2 (A)
* 4
* 11
* 12 (c1)
* 13 (c2)
* 16
* 18
* 22 (i)
* 25
* 27

Variable|

* T
* U
* AH
* AK
* AR
* BM
* V636
* V728
* V884
* V905
* V913
* V915
* V918
* V919
* V921
* V957
* V973
* V1033
* V1036
* V1040
* V1073 (k)
* V1094
* V1104
* V1280
* V1309

HR|

* 5910
* 5969
* 6003
* 6017
* 6070 (d)
* 6094
* 6272
* 6628
* 6675
* 6682

HD|

* 144941
* 145377
* 149274
* 150248
* 153950 (Rapeto)
* 155448
* 159868
* 162020

Other|

* Gliese 667
* Gliese 682
* EPIC 204278916
* EPIC 204376071
* GCRT J1745−3009
* HIP 79431 (Sharjah)
* IGR J17091-3624
* IRAS 17163−3907
* K2-24
* K2-33
* LSS 4067
* MOA-2008-BLG-310L
* OAO 1657-415
* OGLE-2005-BLG-071L
* OGLE-2005-BLG-390L
* OGLE-2006-BLG-109L
* Oph 162225-240515
* Pismis 24-1
* PSR B1620−26
* PSR J1614−2230
* ROXs 12
* 1RXS J160929.1−210524
* Scorpius X-1
* Trumpler 27-1
* UScoCTIO 108
* VVV-WIT-07
* WASP-17 (Dìwö)
* WR 86
* WR 93b
* Wray 17-96

| Exoplanets|

* HD 145377 b
* HD 153950 b (Trimobe)
* HD 159868 b
* HIP 78530 b
* HIP 79431 b (Barajeel)
* K2-24b
* c
* K2-33b
* K2-38b
* OGLE-2005-BLG-071Lb
* OGLE-2005-BLG-390Lb
* OGLE-2007-BLG-368Lb
* PSR B1620−26 b
* WASP-17b (Ditsö̀)
* V921 Scorpii b

|

Star
clusters|

| NGC|

* 6124
* 6139
* 6144
* 6231
* 6242
* 6256
* 6281
* 6380
* 6388
* 6400
* 6441
* 6453
* 6480
* 6496

|

Other|

* Messier 4
* Messier 6
* Messier 7
* Messier 80
* Trumpler 27

Nebulae|

| NGC|

* 6072
* 6153
* 6302
* 6334
* 6337
* 6357

|

Galaxies|

| NGC|

* 6000

|

Other|

* PKS 1622-297
* TXS 1545-234

Category
*[RA:]: Right Ascension
*[Dec.:]: Declination
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*[t]: Discuss this template
*[e]: Edit this template