Abstract
Giant stellar flares can release large amounts of energy within a few days1,2,3,4,5,6,7: X-ray emission alone can be up to ten per cent of the star's bolometric luminosity. These flares exceed the luminosities of the largest solar flares by many orders of magnitude, which suggests that the underlying physical mechanisms supplying the energy are different from those on the Sun. Magnetic coupling between the components in a binary system or between a young star and an accretion disk has been proposed3,7,8,9 as a prerequisite for giant flares. Here we report X-ray observations of a giant flare on Algol B, a giant star in an eclipsing binary system. We observed a total X-ray eclipse of the flare, which demonstrates that the plasma was confined to Algol B, and reached a maximum height of 0.6 stellar radii above its surface. The flare occurred around the south pole of Algol B, and energy must have been released continuously throughout its life. We conclude that a specific extrastellar environment is not required for the presence of a flare, and that the processes at work are therefore similar to those on the Sun.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Kürster,M. & Schmitt,J. H. M. M. Forty days in the life of CF Tucanae (=HD 5303). The longest stellar X-ray flare observed with ROSAT. Astron. Astrophys. 311, 211–229 (1996).
Foing,B. H. et al. in IAU Colloq. 153: Magnetodynamic Phenomena in the Solar Atmosphere—Prototypes of Stellar Magnetic Activity (eds Uchida, Y., Kosugi, T. & Hudson, H. S.) 283–284 (Kluwer Academic, Dordrecht, 1996).
Graffagnino,V. G., Wonnacott,D. & Schaeidt,S. HR 5110 superflare: an interbinary flare identified? Mon. Not. R. Astron. Soc. 275, 129–142 (1995).
Ottmann,R. & Schmitt,J. H. M. M. ROSAT observation of a giant X-ray flare on Algol: evidence for abundance variations? Astron. Astrophys. 307, 813–823 (1996).
Preibish,T., Zinnecker,H. & Schmitt,J. H. M. M. ROSAT-detection of a giant X-ray flare on LkH-α 92. Astron. Astrophys. 279, L33–L366 (1993).
Preibisch,T., Neuhäuser,R. & Alcala,J. M. A giant X-ray flare on the young star P1724. Astron. Astrophys. 304, L13–L16 (1996=5).
Grosso,N., Montmerle,T., Feigelson,E. D., Andre,P., Casanova,S. & Gregorio-Hetem,J. An X-ray superflare on an infrared protostar. Nature 387, 56–58 (1997).
Ferreira,J. M. On the problem of very energetic flares in binary systems. Astron. Astrophys. 335, 248–254 (1998).
Van den Oord,G. H. J. Filament support and flares in binaries. Astron. Astrophys. 205, 167–180 (1988).
Schmitt,J. H. M. M., Fleming,T. A. & Giampapa,M. S. The X-ray view of the low-mass stars in the solar neighborhood. Astrophys. J. 450, 392–400 (1995).
Schmitt,J. H. M. M. Coronae on solar-like stars. Astron. Astrophys. 318, 215–230 (1997).
Forbes,T. G. in Magnetic Reconnection in the Solar Atmosphere (eds Bentley, R. D. & Mariska, J. T.) Vol. 111, 259–267 (ASP Conf. Ser., 1997).
Hudson,H. S. & Khan,J. I. in Magnetic Reconnection in the Solar Atmosphere (eds Bentley, R. D. & Mariska, J. T.) Vol. 111, 135–144 (ASP Conf. Ser., 1997).
Tsuneta,S. in Magnetic Reconnection in the Solar Atmosphere (eds Bentley, R. D. & Mariska, J. T.) Vol. 111, 409–418 (ASP Conf. Ser., 1997).
Al-Naimiy,H. M. K., Mutter,A. A. A. & Flaih,H. A. UBV photometry and light-curve analysis of Algol. Astrophys. Space Sci. 108, 227–236 (1985).
Stern,R. A., Uchida,Y., Tsuneta,S. & Nagase,F. Ginga observations of X-ray flares on Algol. Astrophys. J. 400, 321–329 (1992).
Van den Oord,G. H. J. & Mewe,R. The X-ray flare and the quiescent emission from Algol as detected by OXOSAT. Astron. Astrophys. 213, 245–260 (1989).
White,N. E., Culhane,J. L., Parmar,A. N., Kellett,B. J., Kahn,S., Van den Oord,G. H. J. & Kuijpers,J. An EXOSAT observation of quiescent and flare coronal X-ray emission from Algol. Astrophys. J. 301, 262–274 (1997).
Boella,G., Butler,R. C., Perola,G. C., Piro,L., Scarsi,L. & Bleeker,J. A. M. The medium-energy concentrator spectrometer on board the BeppoSAX X-ray astronomy satellite. Astron. Astrophys. (suppl.) 122, 327–340 (1997).
Favata,F. & Schmitt,J. H. M. M. Spectroscopic analysis of a superhot giant flare observed on Algol by BeppoSAX. Astron. Astrophys. (accepted).
Tsuneta,S. Structure and dynamics of magnetic reconnection in a solar flare. Astrophys. J. 456, 840–849 (1996).
Strassmeier,K. G. in 176th IAU Symp. on Stellar Surface Structure (eds Strassmeier, K. G. & Linsky, J. L.) 289–298 (Kluwer Academic, Dordrecht, 1996).
Byrne,P. B. in 176th IAU Symp. on Stellar Surface Structure (eds Strassmeier, K. G. & Linsky, J. L.) 299–303 (Kluwer Academic, Dordrecht, 1996).
Saar,S. H. in IAU Colloq. 153: Magnetodynamic Phenomena in the Solar Atmosphere—Prototypes of Stellar Magnetic Activity (eds Uchida, Y., Kosugi, T. & Hudson, H. S.) 367–374 (Kluwer Academic, Dordrecht, 1996).
Masuda,S., Kosugi,S., Hara,H., Tsuneta,S. & Ogawara,Y. A loop-top hard X-ray source in a compact solar flare as evidence for magnetic reconnection. Nature 371, 495–497 (1994).
Hudson,H. S. & Nitta,N. in High Energy Solar Physics (eds Ramaty, R., Mandzhavidze, N. & Hua, X.-M.) 374, 285–293 (AIP Conf. Proc., 1996).
Bray,R. J., Cram,L. E., Durrant,C. J. & Loughhead,R. E. Plasma loops in the solar corona. Cambridge Astrophys. Ser. 18, 239 (1991).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Schmitt, J., Favata, F. Continuous heating of a giant X-ray flare on Algol. Nature 401, 44–46 (1999). https://doi.org/10.1038/43389
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/43389
This article is cited by
-
The high energy Universe at ultra-high resolution: the power and promise of X-ray interferometry
Experimental Astronomy (2021)
-
A large coronal loop in the Algol system
Nature (2010)
-
X-ray spectroscopy of stars
The Astronomy and Astrophysics Review (2009)
-
Magnetic activities on young stars
Earth, Planets and Space (2001)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.