V455 And
V515 And
AE Aqr
FO Aqr
V349 Aqr
XY Ari
V405 Aur
V647 Aur
HT Cam
MU Cam
DW Cnc
V709 Cas
V1025 Cen
V1033 Cas
TV Col
TX Col
UU Col
V2069 Cyg
V2306 Cyg
DO Dra
PQ Gem
V418 Gem
DQ Her
V1323 Her
V1460 Her
V1674 Her
EX Hya
NY Lup
V2400 Oph
V2731 Oph
V3037 Oph
V598 Peg
GK Per
AO Psc
HZ Pup
V667 Pup
WX Pyx
V1223 Sgr
V4743 Sgr
CC Scl
V1062 Tau
AX J1740.1
AX J1832.3
AX J1853.3
CTCV J2056
CXO J174954
IGR J04571
IGR J08390
IGR J15094
IGR J16500
IGR J16547
IGR J17014
IGR J17195
IGR J18151
IGR J18173
IGR J18308
IGR J19267
PBC J0927.8
PBC J1841.1
RX J1804
RX J2015
RX J2113
RX J2133
RX J2306
Swift J0717
Swift J1839
Swift J2006
Swift J2138

Full Catalog

Related Systems

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XY Arietis = H0253+193

Links to this object in VSX and in Swift BAT 157 month survey

A non-finding chart for XY Ari

SkyView image of the XY Ari region of the sky (see important notes). This image intentionally left blank, you are staring at the heart of the nearby molecular cloud, MBM 12/Lynds 1457.

  • Equatorial: 02h56m08.15s, +19d26m33.8s (J2000)
  • Galactic: l=159.25, b=-34.49
Finding Chart:
None published (not even in tne IR).
Optical ?; X-rays: 3.0x10-11 ergs cm-2s-1 (BAT 157m; 14-195 keV), 1.4x10-11 ergs cm-2s-1 (4XMM-DR11)
IP Credential:
***** (Ironclad) Eclipses allow one to determine the orbital period with confidence, and the spin period has been detected in multiple independent X-ray observations.
  • Orbital: 0.25269664 d = 6.06471936 hr= 21832.9897 (X-ray eclipses, IR light curves).
    Mid Eclipse = HJD 2447751.8398(1) + 0.25269664 (6) E
    (Allan et al 1996)
  • Spin: 0.00239d = 3.44 min = 206.3s, seen in X-rays.
    No good spin ephemeris known?
  • Others:
80-84 (Hellier 1997)
270+/-100 pc (Littlefair, Dhillon & Marsh 2001)


  1. Halpern & Patterson 1987 (X-rays)
  2. Takano, Koyama & Makishima 1989 (X-rays)
  3. Clemens & Leach 1989 (optical & infrared)
  4. Bhat 1990 (neutron star model)
  5. Patterson & Halpern 1990 (IP behind a molecular cloud)
  6. Koyama et al. 1991 (X-rays, infrared & radio)
  7. Kamata, Tawara & Koyama 1991 (X-rays)
  8. Zuckerman et al. 1992 (infrared photometry)
  9. Kamata & Koyama 1993 (X-rays)
  10. Allan, Hellier & Ramseyer 1996 (infrared photometry)
  11. Hellier 1997 (X-ray eclipse timings)
  12. Hellier, Mukai & Beardmore 1997 (X-rays during outburst)
  13. Hellier, Mukai & Osborne 1998 (X-ray spectroscopy)
  14. Ramsay et al. 1998 (X-ray spectroscopy)
  15. Ezuka & Ishida 1999 (X-ray spectroscopy)
  16. Cropper et al. 1999 (post-chock model with gravity)
  17. Ramsay 2000 (X-ray spectroscpy)
  18. Littlefair, Dhillon & Marsh 2001 (infrared spectroscopy)
  19. Salinas & Schlegel 2004 (X-rays)
  20. Norton & Mukai 2007 (X-ray timing)
  21. Brunschweiger et al. 2009 (X-rays)
  22. Scaringi et al. 2010 (X-rays)
  23. Anzolin et al. 2010 (X-ray flickering)
  24. Yuasa et al. 2010 (X-ray spectroscopy)
  25. Galis et al. 2010 (X-rays)
  26. Pretorius & Mukai 2014 (space density)
  27. Hameury & Lasota 2017 (disk instability model for IPs)
  28. Barrett et al. 2017 (radio)
  29. Zengin Camurdan, Balman & Burwitz 2018 (X-rays)
  30. Schwope 2018 (space density)
  31. Suleimanov, Doroshenko & Werner 2019 (X-ray spectroscopy)

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Please send your comments, suggestions etc. to Koji.Mukai@nasa.gov and/or Koji.Mukai@umbc.edu
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