NGC 6572
|
Planetary Nebula NGC 6572 |
|
|---|---|
|
|
| Photo from the Hubble Space Telescope | |
| AladinLite | |
| Constellation | Snake bearer |
|
Position equinox : J2000.0 |
|
| Right ascension | 18h 12m 06.2s |
| declination | + 06 ° 51 ′ 13 ″ |
| Appearance | |
| Apparent brightness (visual) | 8.1 likes |
| Apparent brightness (B-band) | 9.0 mag |
| Angular expansion | 0.25 ′ × 0.25 ′ |
| Central star | |
| designation | HD 166802 |
| Apparent brightness | 13.6 mag |
| Physical data | |
| Redshift | (-29 ± 3) · 10 −6 |
| Radial velocity | (-8.7 ± 0.9) km / s |
| distance | 2500 ly |
| Age | 2,600 years |
| history | |
| discovery | Wilhelm Struve |
| Date of discovery | July 18, 1825 |
| Catalog names | |
| NGC 6572 • PK 34 + 11.1 • GC 4390 • h 2000 • CS 13.6 • Struve 6 | |
NGC 6572 is the name of a planetary nebula in the constellation Serpent Bearer . NGC 6572 has an angular extent of 0.6 × 0.4 arc minutes and a magnitude of 8.1 mag. Its central star, a white dwarf , shines with an apparent magnitude of 13.6 mag. The distance is estimated to be 2500 light years , from which the apparent size results in an extension of approx. 0.1 × 0.15 light years.
The object was discovered in 1825 by the German astronomer Friedrich Georg Wilhelm Struve .
description
NGC 6572 is a very young and therefore still a small, very bright planetary nebula, the central star of which shed its gas envelope around 2,600 years ago. The gas cloud is currently expanding at a speed of around 15 km / s. The extremely hot central star is relatively low-mass with around 0.57 solar masses and stimulates the surrounding gas cloud to glow with its hard UV radiation. The dominant spectral lines CII, NII and OII give the nebula its intense turquoise color.
Visual observation
NGC 6572 is very easy to find because it is located almost exactly 3 ° south-south-east ("5 o'clock") of the star 72 Ophiuchi (3.73 Mag). At 100x magnification, NGC 6572 is immediately noticeable due to its remarkable brightness and turquoise color, especially since there are no brighter stars in the field of view. At 260x magnification, the slightly oval shape of NGC 6572 can be clearly seen, but the nebula in the eyepiece remains overall without structure. The central star cannot be seen in the eyepiece, it is probably completely outshone by the bright gas cloud.