NGC 40, the Bow Tie Nebula, is an unusual red planetary nebula located in the constellation of Cepheus.

Although it is relatively small with an apparent size of 72 x 60 arcseconds, it is bright at magnitude 10.3, and easily observed and photographed, even from observing locations compromised by light pollution. Its central star is also easily visible at magnitude 11.5.

Noted observer and professional astronomer Brian Skiff points out that NGC 40 is something of a peculiarity as far as planetary nebula go. Its central star has the spectra of a massive Wolf-Rayet star, but its brightness is approximately 10,000 times less luminous than that type of star. Planetary nebula usually form around stars that have masses similar to the Sun and not massive Wolf-Rayet stars. He says this discrepancy was noted by Williamina Fleming more than 100 years ago, but the puzzle is still not solved.

NGC 40 is located 3,500 light-years away. At that distance its true size would be 1.2 light-years in diameter.

NGC 40 was discovered by William Herschel on November 25, 1788.

North is to the top in the above image.

NGC 40 Catalogs: NGC 40, PK 120+9.1 Common Name: Bow Tie Nebula Object Type: Planetary Nebula Magnitude: 10.3v Size: 72" x 60" Constellation: Cepheus Image Field Centered At: RA: 00h 13m 09s Dec: +72° 32' 25"