V445 Puppis
| V445 Puppis | |
 Foto av gasskalet som omger V445 Puppis, från 2005 (uppe till vänster) till 2007 (nere till höger) | |
| Observationsdata Epok: J2000.0 | |
|---|---|
| Stjärnbild | Akterskeppet |
| Rektascension | 07t 37m 59,90s |
| Deklination | -25° 56′ 58,9″ |
| Skenbar magnitud () | +8,6 (i maximum),[1] +21 (i minimum) |
| Stjärntyp | |
| Variabeltyp | Nova (NC) |
| Astrometri | |
| Avstånd | 27000 lå (8200 pc) |
| Detaljer | |
| Metallicitet | |
| Andra beteckningar | |
| Nova Puppis 2000, AAVSO 0733-25, ASAS J073757-2557.0 | |
V445 Puppis eller Nova Puppis 2000 var en ljusstark nova i stjärnbilden Akterskeppet som nådde sitt maximum i februari 2000. [2] Den upptäcktes av Kazuyoshi Kanatsu i Matsue i Shimane prefekturen, Japan. Han noterade novans maximum till +8,6 i magnitud den 28 november 2000.[3][4][5]
Positionen för novan överensstämde med en stjärna av magnitud +13,1 som blivit fotograferad 1967.[6]
Den vita dvärgen i V445 Puppis-systemet har en massa som uppskattats till drygt 1,3 M☉ (solmassor) och ökar på grund av att den får ta emot material från sin följeslagare. När den vita dvärgen närmar sig Chandrasekhars gränsmassa vid 1,38 solmassor kommer den förmodligen att få ett utbrott som supernova (typ Ia).[7]
Se även
Referenser
- ^ ”Basic data : V445 Pup -- Nova”. SIMBAD. Centre de Données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=V445+Puppis&submit=SIMBAD+search. Läst 30 april 2015.
- ^ ”VSX for V445 Pup”. The International Variable Star Index. AAVSO. http://www.aavso.org/vsx/index.php?view=detail.top&oid=27047. Läst 20 september 2013.
- ^ ”WebObs Search Results for V445 Pup”. American Association of Variable Star Observers. AAVSO. http://www.aavso.org/apps/webobs/results/?star=V445+Pup&num_results=25&obs_types=all. Läst 20 september 2013.
- ^ ”Variable Star Plotter (VSP) for V445 Pup”. American Association of Variable Star Observers. AAVSO. http://www.aavso.org/vsp/chart. Läst 20 september 2013.
- ^ ”IAUC 7552: Possible Nova in Puppis”. IAU Central Bureau for Astronomical Telegrams. IAU. http://www.cbat.eps.harvard.edu/iauc/07500/07552.html. Läst 20 september 2013.
- ^ ”Circular No. 7556”. IAU Central Bureau for Astronomical Telegrams. IAU. http://www.cbat.eps.harvard.edu/iauc/07500/07556.html. Läst 20 september 2013.
- ^ Kato, Hachisu, Kiyota, Saio (2008). ”Helium Nova on a Very Massive White Dwarf: A Revised Light-Curve Model of V445 Puppis (2000”. The Astrophysical Journal 684 (2): sid. 1366-1373.
Media som används på denna webbplats
V445-Puppis.jpg
Författare/Upphovsman: ESO/P.A. Woudt, Licens: CC BY 4.0
Using the NACO adaptive optics instrument on ESO’s Very Large Telescope and its ability to obtain images as sharp as if taken from space, astronomers have made the first time-lapse movie of a bipolar shell ejected by a “vampire star”, which underwent an outburst after gulping down part of its companion’s matter. This enabled them to determine the distance and intrinsic brightness of the object. It appears that this system is a prime candidate to be one of the long-sought progenitors of the exploding stars known as Type Ia supernovae, critical for the study of dark energy. The images of V445 Puppis cover a time span of two years. The images unambiguously show a bipolar shell, initially with a very narrow waist, with lobes on each side. Two knots are also seen at either extreme end of the shell, which appear to move at about 30 million kilometres per hour. The shell — unlike any previously observed for a nova — is itself moving at about 24 million kilometres per hour. A thick disc of dust, which must have been produced during the last outburst, obscures the central couple of stars.
Författare/Upphovsman: ESO/P.A. Woudt, Licens: CC BY 4.0
Using the NACO adaptive optics instrument on ESO’s Very Large Telescope and its ability to obtain images as sharp as if taken from space, astronomers have made the first time-lapse movie of a bipolar shell ejected by a “vampire star”, which underwent an outburst after gulping down part of its companion’s matter. This enabled them to determine the distance and intrinsic brightness of the object. It appears that this system is a prime candidate to be one of the long-sought progenitors of the exploding stars known as Type Ia supernovae, critical for the study of dark energy. The images of V445 Puppis cover a time span of two years. The images unambiguously show a bipolar shell, initially with a very narrow waist, with lobes on each side. Two knots are also seen at either extreme end of the shell, which appear to move at about 30 million kilometres per hour. The shell — unlike any previously observed for a nova — is itself moving at about 24 million kilometres per hour. A thick disc of dust, which must have been produced during the last outburst, obscures the central couple of stars.