Crab Nebula, Messier 1,(JWST)

Crab Nebula,Messier 1, The Crab Nebula is the remnant of the of a star 6-10x the size of the Sun and is the result of a supernova seen in 1054 AD.  The Crab Nebula spans about 13 light years and is about 6 arc seconds in size in the sky or about 1/5 of the size of the full moon. It is 6500 light years distant.  In the nebula’s center lies a neutron star: a star as massive as the Sun but is only 30 kilometers in size. Supernovae from large dying stars 6-10X the size of the Sun either result in a neutron star or a black hole. In this case the remnant is a neutron star and can be located in the image as the a small dim star near the center of the image surrounded by a bluish ellipitical halo that is only visible in this JWST image.  This halo follows the magnetic field of the neutron star which causes charged particles to emit light called synchrotron radiation.    The neutron star rotates about 30 times each second with extreme precision similiar to an atomic clock and emits a beam of energy along its poles ranging from radio frequencies to gamma rays. At X-ray wavelengths (above 1 keV), it is one of the brightest, continuously emitting sources in the sky. At optical wavelengths it is quite dim but is 1000X brighter than any other known neutron star in the sky and as such is visible in this image. Such a neutron star is referred to as a Pulsar. The beam is the result of the rotational energy of the neutron star, which generates an electrical field from the movement of its very strong magnetic field, resulting in the acceleration of protons and electrons on the star surface and the creation of an electromagnetic beam emanating from the poles of the magnetic field. The It is described as a “lighthouse” emitting a regular pulsating beam of light. The rotating beam is caused by a miss alignment of the rotation axis and the magnetic field axis.  The nebula surrounding the neutron star was created by the remnant gas and dust from the star explosion. It is expanding at a rate of 1500km/sec, 0.5% of the speed of light.

This image done by the James Webb Space Telescope in infrared provides an interesting complement to the Hubble telescope image done in visual light.https://earthandskyimaging.com/product/crab-nebula-messier-1/ It is a combination of 5 images done by the near infrared camera, NIRCAM and the mid range infrared camera(MIRI). The two images seem to have similiar colors inspite of the difference in wavelengths, but they are both false color images. The crisscrossing bands in the Hubble image come from the  0.5 u wavelength associated with doubly ionized oxygen but the bands only showed up in the 18u and 21u MIRI images. These bands are fractured parts of the nebula that has been broken up by the outward pressure of the neutron star. One of the most interesting aspects of the Webb image not visible in the Hubble image is the large  multiple banded elliptical  bluish synchrotron radiation tracks which shows up in great detail around the neutron star.  These bands are most prominent in the 1.6u radiation and are bluish in this image which are more apparent than the whitish bands in the NASA version. Like with the Hubble image I have chosen to lower the exposure and enhance the color to bring out more detail than is visible in the NASA image. https://www.nasa.gov/missions/webb/the-crab-nebula-seen-in-new-light-by-nasas-webb/

This image like the Hubble image of the Crab nebula was difficult to process. The main difficulty here was that it is a combination of images from the NIRCAM and MIRI cameras which have different focal lengths and different field of views. In addition, the MIRI images, in particular,  had a significant amount of artifact defects in the images that needed to be removed.