NGC 2264

NGC 2264: Cone Nebula at bottom with inverted Christmas Tree cluster above the cone. Image credit: ESO

  The Cone Nebula is actually a mass of gas and dust located 2,500 light-years away in the constellation of the Unicorn. The NGC 2264 nebula has a conical shape, the red color is emitted by the hydrogen gas that has been stimulated by the large amount of ultraviolet radiation, coming from hot blue stars in the region. 

  This nebula has the particularity of being a variable luminosity, due to the star that illuminates the cloud, and that varies of irregular form. This photo (Image NGC 2264) shows a cone of 2.5 light years. The pillar has a full size of seven light years. Radiation from young and hot stars (at the top of the image), slowly eroding the top of the nebula.

An infrared Spitzer Space Telescope image of NGC 2264. Image credit: NASA/ESA

NGC 2371

  NGC 2371/2. Image source: (1)

  NGC 2371, is a planetary nebula, the bright remains of a star similar to the Sun. The visible remnant resulting from the explosion of the NGC 2371 superheated core after its red giant stage, now stripped of its outer layers. Its scorching surface temperature is 240,000 degrees Fahrenheit. NGC 2371 is located about 4,300 light years away from Earth in the constellation Gemini. The Hubble image reveals several notable features, especially the prominent pink clouds ejected in the opposite direction of the central star.  

  What also draws attention are the many very small pink points, marking small and dense gas knots, which are also on the sides diametrically opposed to the star. These characteristics appear to represent the expulsion of gas from the star along a specific direction. The direction (of the jet) has changed over time for the last few thousand years.