NGC 2440
Encyclopedia
NGC 2440 is a planetary nebula
, one of many in our galaxy. Its central star, HD62166, is possibly the hottest known white dwarf
. The nebula is situated in the Puppis
constellation
.
It was discovered by William Herschel
on March 4, 1790. He described it as "a beautiful planetary nebula of a considerable degree of brightness, not very well defined." The nebula is located about 1.23 kiloparsecs (3.79×1019 m) or about 4,000 light years from the Sun
.
and 0.028 solar radius, has an apparent magnitude of 17.5..
Planetary nebula
A planetary nebula is an emission nebula consisting of an expanding glowing shell of ionized gas ejected during the asymptotic giant branch phase of certain types of stars late in their life...
, one of many in our galaxy. Its central star, HD62166, is possibly the hottest known white dwarf
White dwarf
A white dwarf, also called a degenerate dwarf, is a small star composed mostly of electron-degenerate matter. They are very dense; a white dwarf's mass is comparable to that of the Sun and its volume is comparable to that of the Earth. Its faint luminosity comes from the emission of stored...
. The nebula is situated in the Puppis
Puppis
Puppis is a constellation in the southern sky. Its name is the Latin word for the poop deck of a ship, and Puppis represents the deck of the ship and its deckhouses...
constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
.
It was discovered by William Herschel
William Herschel
Sir Frederick William Herschel, KH, FRS, German: Friedrich Wilhelm Herschel was a German-born British astronomer, technical expert, and composer. Born in Hanover, Wilhelm first followed his father into the Military Band of Hanover, but emigrated to Britain at age 19...
on March 4, 1790. He described it as "a beautiful planetary nebula of a considerable degree of brightness, not very well defined." The nebula is located about 1.23 kiloparsecs (3.79×1019 m) or about 4,000 light years from the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
.
HD62166
HD62166 has an exceptionally high surface temperature of about 200,000 kelvins and a luminosity 1,100 times that of the Sun. This dense star, with an estimated 0.6 solar massSolar mass
The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...
and 0.028 solar radius, has an apparent magnitude of 17.5..