NGC 2440
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Planetary nebula data from NGC 2440 |
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| Photo from the Hubble Space Telescope | |
| AladinLite | |
| Constellation | Aft deck of the ship |
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Position equinox : J2000.0 |
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| Right ascension | 07h 41m 55.3s |
| declination | -18 ° 12 ′ 30 ″ |
| Appearance | |
| Apparent brightness (visual) | 9.4 mag |
| Apparent brightness (B-band) | 10.8 mag |
| Angular expansion | 1.32 ′ × 1.32 ′ |
| Central star | |
| designation | HD 62166 |
| Apparent brightness | 17.7 mag |
| Physical data | |
| Redshift | +0.000209 |
| Radial velocity | +62.7 km / s |
| distance | 1600 ly |
| history | |
| discovery | William Herschel |
| Date of discovery | March 4, 1790 |
| Catalog names | |
| NGC 2440 • PK 234 + 2.1 • ESO 560-PN9 • GC 1567 • H IV 64 • h 3095 • CS = 14.3 | |
NGC 2440 is the name of a planetary nebula in the constellation Puppis . NGC 2440 has an angular extent of around 1.32 arc minutes and a magnitude of 9.4 mag. Its central star , a white dwarf , is the hottest known star with a surface temperature of almost 200,000 K and glows in visible light with an apparent brightness of 17.7 mag. Its absolute luminosity exceeds that of our sun by 250 times.
The gas clouds ejected by this central star show two very different regions that evidently formed in different periods of time: a bright inner region with two pronounced focus of brightness, hence the name insect nebula, which is sometimes used , and a much fainter outer area with a far greater extent. The distance of NGC 2440 to our solar system is generally estimated to be 1,600 light years .
The planetary nebula NGC 2440 was discovered on March 4, 1790 by the German-British astronomer Wilhelm Herschel .
Visual observation
NGC 2440 is one of the visually brighter planetary nebulae, just bright enough to be photographed with a commercially available webcam on a medium-sized instrument (photo on the left). Finding it is very easy: just under 9 ° north is the 3.9 mag bright asterisk α Monocerotis in the unicorn . Halfway to NGC 2440, in a precisely southerly direction, you inevitably pass NGC 2438 , another planetary nebula.
In the eyepiece of a medium-sized instrument with an 8 "aperture, NGC 2440 shows itself at approx. 260x magnification as a small, pale and diffuse fog, the shape of which is more reminiscent of a gummy bear.