| 释义 |
- References
- Notes
{{Starbox begin
| name=EV Lacertae
}}{{Starbox image
| image=
| caption=Artist's conception of a flare explosion on EV Lacertae.
}}{{Starbox observe
| epoch=J2000
| ra={{RA|22|46|49.7323}}[1]
| dec={{DEC|+44|20|02.368}}[1]
| appmag_v=10.09[3]
| constell=Lacerta
}}{{Starbox character
| class=M3.5[4]
| b-v=+1.36[5]
| u-b=+0.83[5]
| variable=Flare star
}}{{Starbox astrometry
| radial_v=–1.5[7]
| prop_mo_ra=–704.65[1]
| prop_mo_dec=–459.41[1]
| parallax=199.3
| p_error=0.93
| parallax_footnote={{r|Gatewood1993}}
| absmag_v=
}}{{Starbox detail
| mass=0.35[10]
| radius=0.36[10]
| luminosity=
| temperature={{nowrap|3,400 ± 18}}[12]
| metal_fe={{nowrap|–0.01 ± 0.17}}[12]
| rotation=4.376 days[14]
| rotational_velocity=4.5[10]
| gravity=
| age=
}}{{Starbox catalog
| names=GJ 873, BD+43 4305, LHS 3853, LTT 16695, HIP 112460, PLX 5520
}}{{Starbox reference
|Simbad=EV+Lac
}}{{Starbox end}}EV Lacertae (EV Lac, Gliese 873, HIP 112460) is a faint red dwarf star 16.5 light years away in the constellation Lacerta. It is the nearest star to the Sun in that region of the sky, although with an apparent magnitude of 10, it is only barely visible with binoculars. EV Lacertae is spectral type M3.5 flare star that emits X-rays.On 25 April 2008, NASA's Swift satellite picked up a record-setting flare from EV Lacertae.[17] This flare was thousands of times more powerful than the largest observed solar flare. Because EV Lacertae is much farther from Earth than the Sun, the flare did not appear as bright as a solar flare. The flare would have been visible to the naked eye if the star had been in an observable part of the night sky at the time. It was the brightest flare ever seen from a star other than the Sun. EV Lacertae is much younger than the Sun. Its age is estimated at 300 million years, and it is still spinning rapidly. The fast spin, together with its convective interior, produces a magnetic field much more powerful than the Sun's. This strong magnetic field is believed to play a role in the star's ability to produce such bright flares. After the flare, the star was blue.[1] References1. ^https://m.youtube.com/watch?v=rqsckfsXU8U
2. ^1 {{cite web | first=Brian | last=Dunbar | editors=Smith, Yvette | title=Pipsqueak Star Unleashes Monster Flare | publisher=NASA | date=May 20, 2008 | url=http://www.nasa.gov/multimedia/imagegallery/image_feature_1087.html | accessdate=2010-06-12 }}
3. ^1 {{cite web | title=V* EV Lac -- Flare Star | work=SIMBAD | publisher=Centre de Données astronomiques de Strasbourg | url=http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=EV+Lac | accessdate=2010-06-12 }}
4. ^1 2 3 4 {{cite journal | author=Perryman, M. A. C. |display-authors=etal | title=The HIPPARCOS Catalogue | journal=Astronomy & Astrophysics | volume=323 | pages=L49–L52 |date=April 1997 | bibcode=1997A&A...323L..49P }}
5. ^1 {{cite journal |author1=Montes, D. |author2=López-Santiago, J. |author3=Gálvez, M. C. |author4=Fernández-Figueroa, M. J. |author5=De Castro, E. |author6=Cornide, M. | title=Late-type members of young stellar kinematic groups - I. Single stars | journal=Monthly Notices of the Royal Astronomical Society | volume=328 | issue=1 | pages=45–63 |date=November 2001 | doi=10.1046/j.1365-8711.2001.04781.x | bibcode=2001MNRAS.328...45M |arxiv = astro-ph/0106537 }}
6. ^1 {{cite book | last=Wilson | first=Ralph Elmer | year=1953 | title=General Catalogue of Stellar Radial Velocities | publisher=Carnegie Institution of Washington | location=Washington | bibcode=1953GCRV..C......0W }}
7. ^1 2 {{cite journal | last=Erro | first=B. I. | title=Infrared photometry of UV CET stars | journal=Boletin Del Instituto De Tonantzintla | volume=6 | page=143 | year=1971 | bibcode=1971BITon...6..143E }}
8. ^1 2 3 {{cite journal |author1=Phan-Bao, Ngoc |author2=Martín, Eduardo L. |author3=Donati, Jean-François |author4=Lim, Jeremy | title=Magnetic Fields in M Dwarfs: Rapid Magnetic Field Variability in EV Lacertae | journal=The Astrophysical Journal | volume=646 | issue=1 | pages=L73–L76 |date=July 2006 | doi=10.1086/506591 | bibcode=2006ApJ...646L..73P |arxiv = astro-ph/0603480 }}
9. ^1 {{cite journal |author1=Testa, Paola |author2=Drake, Jeremy J. |author3=Peres, Giovanni | title=The Density of Coronal Plasma in Active Stellar Coronae | journal=The Astrophysical Journal | volume=617 | issue=1 | pages=508–530 |date=December 2004 | doi=10.1086/422355 | bibcode=2004ApJ...617..508T |arxiv = astro-ph/0405019 }}
10. ^1 2 {{cite journal | display-authors=1 | last1=Rojas-Ayala | first1=Bárbara | last2=Covey | first2=Kevin R. | last3=Muirhead | first3=Philip S. | last4=Lloyd | first4=James P. | title=Metallicity and Temperature Indicators in M Dwarf K-band Spectra: Testing New and Updated Calibrations with Observations of 133 Solar Neighborhood M Dwarfs | journal=The Astrophysical Journal | volume=748 | issue=2 | page=93 |date=April 2012 | doi=10.1088/0004-637X/748/2/93 | bibcode=2012ApJ...748...93R | arxiv=1112.4567 | url=http://authors.library.caltech.edu/31363/1/RojasAyala2012p18033Astrophys_J.pdf }}
11. ^{{cite journal |last1=Gatewood |first1=George |last2=de Jonge |first2=Kiewiet Joost |last3=Stephenson |first3=Bruce |title=One-milliarsecond precision parallax studies in the regions of Delta Cephei and EV Lacertae |year=1993 |journal=Publications of the Astronomical Society of the Pacific |volume=105 | issue=692 | pages=1101–1106 |arxiv= |doi=10.1086/133287 |bibcode=1993PASP..105.1101G}}
}}Notes{{reflist|group=nb}}{{Nearest systems|4}}{{Stars of Lacerta}} 5 : Lacerta (constellation)|M-type main-sequence stars|Objects with variable star designations|Flare stars|Ursa Major Moving Group |