Depth 37 · Pulsar wind nebula

Crab Nebula

The Crab Nebula is the expanding debris of a star that exploded as a supernova seen from Earth in 1054. At its heart is a pulsar, a city-sized neutron star spinning about 30 times a second, which energises the surrounding cloud and makes it one of the most studied objects in the sky.

Fact sheet

Type

Supernova remnant and pulsar wind nebula

Distance

About 6,500 light-years from Earth

Size

About 6 light-years across

Constellation

Taurus

Position in the sky

Right ascension 5h 35m, declination +22° 01′

Seeing it from Earth

At about magnitude 8.4 it is too faint for the naked eye but can be found with a small telescope, and NASA lists January as the best month to look.

On the voyage

Depth 37, in the Milky Way section of the route, between the Ring Nebula and the Eagle Nebula

Things to know

• Chinese astronomers recorded the 1054 supernova as a 'guest star' that could be seen in daylight for nearly a month. NASA
• English astronomer John Bevis found the nebula in 1731, and Charles Messier's later sighting of it, which he first took for a comet, prompted him to start his famous catalogue. NASA
• The central pulsar is a neutron star only about 20 km (12 miles) wide that rotates about 30 times per second and pours out roughly 100,000 times the Sun's energy. NASA Chandra
• Comparing Hubble images taken about 25 years apart shows the nebula's filaments moving outward at about 5.5 million km per hour. ESA/Hubble
• Webb's measurements of nickel and iron suggest the explosion may have been a weak iron-core collapse, not only the rarer electron-capture type that earlier studies favoured. NASA

Sources

• NASA – Messier 1 (The Crab Nebula)
• Chandra – Crab Nebula fact sheet
• ESA/Hubble – Hubble revisits Crab Nebula to track 25 years of expansion (heic2607)
• NASA – Investigating the Origins of the Crab Nebula With NASA's Webb