Sh2-240, also known as Simeis 147 or the Spaghetti Nebula, is a supernova remnant (SNR) located on the border between the constellations Taurus and Auriga. It is about 3,000 light-years away and spans approximately 150 light-years in diameter, making it one of the largest and most diffuse supernova remnants visible from Earth. 

Believed to be the result of a supernova explosion around 40,000 years ago, Sh2-240 consists of intricate filaments of ionized gas and faint, tangled structures. It is still interacting with the surrounding interstellar medium, emitting faint optical, radio, and X-ray radiation.   At its core, the remnant likely contains a neutron star or pulsar, the collapsed core of the original massive star that exploded.