NGC 5189
| NGC 5189 | |
 Bild på NGC 5189 tagen med Rymdteleskopet Hubble. Foto: HST/NASA/ESA | |
| Observationsdata | |
|---|---|
| Typ | Planetarisk nebulosa |
| Stjärnbild | Flugan |
| Rektascension | 13t 33m 32,97 s |
| Deklination | -65° 58′ 26,7″ |
| Avstånd | ca 3 000 (900 pc) ljusår |
| Skenbar storlek | 90 x 62 bågsekunder |
| Skenbar magnitud | 8,2 |
| Noterbart | En speciell planetarisk nebulosa med en dubbelstjärna i centrum. |
| Upptäckt | |
| Upptäcktsår | 1 juli 1826 |
| Upptäckare | James Dunlop |
| Andra beteckningar | |
| IC 4274, PK 307-3.1, ESO 96-PN16, GC 3570, Gum 47, AM 1329-654, Dun 252, h 3514, HD 117622 | |
| Se även: Nebulosor, Lista över nebulosor | |
NGC 5189 är en planetarisk nebulosa belägen i stjärnbilden Flugan. Den upptäcktes 1 juli 1826 av James Dunlop, som katalogiserade den som Δ252.[1] Ett populärt smeknamn är "Spiralplanetariska nebulosan". Under många år, långt in på 1960-talet, ansågs den vara en ljusstark emissionsnebulosa. Det var Karl Gordon Henize, som 1967 först beskrev NGC 5189 som kvasiplanetarisk baserat på dess spektrala emissionslinjer.
NGC 5189 beräknas befinna sig 1 780 ljusår eller 546 parsek[2]från jorden. Andra mätningar har gett resultat upp till 900 pc (~3 000 ljusår).[3]
Egenskaper
Sedd genom ett teleskop verkar NGC 5189 ha en S-form, som påminner om en stavspiralgalax. S-formen, tillsammans med punktsymmetriska knutar i nebulosan, har länge gett astronomer anledning att förutsätta att en dubbelstjärna finns i nebulosans centrum.[4] Bildanalyser från Hubbleteleskopet har visat att denna S-formade struktur verkligen är två täta lågjoniseringsregioner. Den ena rör sig mot nordost och den andra rör sig mot sydvästra delen av nebulosan,[5] vilket kan vara ett resultat av ett nyligen inträffat utbrott från centralstjärnan. Observationer med Southern African Large Telescope har visat en vit dvärg som följeslagare i en 4,04 dygns omloppsbana kring den sällsynta lågmassestjärnan av Wolf-Rayet-typ i centrum av NGC 5189.[6]
Referenser
- Den här artikeln är helt eller delvis baserad på material från engelskspråkiga Wikipedia, NGC 5189, 27 juli 2021.
Noter
- ^ Classic Deep-Sky and Double Stars : NGC 5189 (Mus) [1] Southern Astronomical Delights
- ^ http://simbad.u-strasbg.fr/simbad/sim-id?Ident=NGC+5189. Hämtad 2012-12-21.
- ^ SABIN L.; VAZQUEZ R.; LOPEZ J.A.; GARCIA-DIAZ M.T.; RAMOS-LARIOS G. (2012). ”The filamentary multi-polar planetary nebula NGC 5189”. Rev. Mex. Astron. Astrofís. 48: sid. 165–76. Bibcode: 2012RMxAA..48..165S. http://www.astroscu.unam.mx/rmaa/RMxAA..48-2/PDF/RMxAA..48-2_lsabin.pdf.
- ^ Phillips J. P.; Reay N. K. (1983). ”Ansae and the precession of central stars in planetary nebulae - The cases of NGC 5189 and NGC 6826”. Astronomy and Astrophysics 117: sid. 33–37. Bibcode: 1983A&A...117...33P.
- ^ Danehkar, A.; Karovska, M.; Maksym, W.P.; Montez Jr., R. (2018). ”Mapping Excitation in the Inner Regions of the Planetary Nebula NGC 5189 using HST WFC3 Imaging”. Astrophys. J. 852 (2): sid. 87. doi:. Bibcode: 2018ApJ...852...87D.
- ^ Manick R.; Miszalski B.; McBride V. (2015). ”A radial velocity survey for post-common-envelope Wolf-Rayet central stars of planetary nebulae: first results and discovery of the close binary nucleus of NGC 5189”. Monthly Notices of the Royal Astronomical Society 448 (2): sid. 1789–1806. doi:. Bibcode: 2015MNRAS.448.1789M.
Externa länkar
Wikimedia Commons har media som rör NGC 5189.- A Cosmic Holiday Ornament, Hubble-Style
- Southern African Large Telescope: Elusive Binary System
Media som används på denna webbplats
A swoosh in space: Merry Christmas from Hubble
The NASA/ESA Hubble Space Telescope celebrates the holiday season with a striking image of the planetary nebula NGC 5189. The intricate structure of the stellar eruption looks like a giant and brightly coloured ribbon in space.
Planetary nebulae represent a final brief stage in the life of a star like the Sun. While consuming the last of the fuel in its core, the star expels a large portion of its outer regions, which then heats up and glows brightly, showing intricate structures that scientists are still trying to fully understand. The structure visible within NGC 5189 is particularly dramatic, and Hubble’s image of the nebula is by far the most detailed yet made of this object [1].
Hubble has been a key tool for studying planetary nebulae for years, and many of its images have become famous. As well as being highly attractive, planetary nebulae tell us about the ultimate fate of the Sun, which will form such a nebula when it runs out of fuel in a little over five billion years.
These nebulae were named by astronomers studying them through early telescopes with little magnification and optics that were far from sharp. The brightly coloured nebulae are often roughly spherical, and many appear green or blue like Uranus and Neptune, so their appearance evoked that of gas giant planets like those in the outer Solar System.
Many of them do indeed look somewhat planetlike, but NGC 5189 certainly does not: the nebula forms a dramatic reverse S-shape.
Looking at the detail of Hubble’s image, possible thanks to Hubble’s very high resolution, the nebula shows a series of dense knots in the clouds of gas. The gas and radiation flowing out from the dying star carves out shapes in the clouds, forming glowing bow-wave-like patterns towards the centre of the nebula.
The knots in NGC 5189 are a reminder of just how vast the planetary nebula is. They might look like mere details in this image, but each and every one is a similar size to the entire Solar System.
The star at the centre of the nebula, a dense white dwarf, is far too small to see as anything other than a point of light, even though it is roughly the size of the Earth.
The overall shape of NGC 5189 can counterintuitively tell us about what is happening on very small scales around the tiny central star. NGC 5189’s shape is reminiscent of a lawn sprinkler, with matter being expelled from the star, which is wobbling as it rotates.
Similar structures have been seen before, especially in planetary nebulae with binary stars at their centres. This is also a likely explanation for the structure of NGC 5189, though to date, only one star has been found at the nebula’s centre. Notes
The Hubble Space Telescope is a project of international cooperation between ESA and NASA.
[1] Previously, the best images of NGC 5189 came from the Gemini Observatory and the European Southern Observatory’s New Technology Telescope. Hubble’s surpasses both in clarity and sharpness.
Image credit: NASA, ESA and the Hubble Heritage Team (STScI/AURA)
About the Object
Name: NGC 5189
Type: • Milky Way : Nebula : Type : Planetary
• Nebulae Images/Videos
Colours & filters Band Wavelength Telescope
Optical [OIII] 502 nm Hubble Space Telescope WFC3 Optical H-alpha 657 nm Hubble Space Telescope WFC3 Optical [SII] 673 nm Hubble Space Telescope WFC3 Optical V 606 nm Hubble Space Telescope WFC3 Infrared I 814 nm Hubble Space Telescope WFC3.
