Normally, space is portrayed as static. With objects thousands of light years across, and tens of thousands of parsecs away, what change could we possibly see from earth?
Yet in this video of the crab nebula, we see a dynamic object expanding, rife with shockwaves and speeding outflows. Over the course of 1260 days (3.5 years), we can see the gas in the nebula expand at a blistering pace by about 163,296,000,000 kilometers, or about 0.017 light years. So what’s causing these outflows?
At the center of the Crab Nebula are two faint stars, one of which is the star responsible for the existence of the nebula. It was identified as such in 1942, when Rudolf Minkowski found that its optical spectrum was extremely unusual. The region around the star was found to be a strong source of radio waves in 1949 and X-rays in 1963, and was identified as one of the brightest objects in the sky in gamma rays in 1967. Then, in 1968, the star was found to be emitting its radiation in rapid pulses, becoming one of the first pulsars to be discovered.
Pulsars are sources of powerful electromagnetic radiation, emitted in short and extremely regular pulses many times a second. They were a great mystery when discovered in 1967, and the team who identified the first one considered the possibility that it could be a signal from an advanced civilization. However, the discovery of a pulsating radio source in the center of the Crab Nebula was strong evidence that pulsars were formed by supernova explosions. They now are understood to be rapidly rotating neutron stars, whose powerful magnetic fields concentrates their radiation emissions into narrow beams.
The Crab Pulsar is believed to be about 28–30 km (17–19 mi) in diameter; it emits pulses of radiation every 33 milliseconds. The energy released as the pulsar slows down is enormous, and it powers the emission of the synchrotron radiation of the Crab Nebula, which has a total luminosity about 75,000 times greater than that of the Sun. The pulsar’s extreme energy output creates an unusually dynamic region at the center of the Crab Nebula. While most astronomical objects evolve so slowly that changes are visible only over timescales of many years, the inner parts of the Crab Nebula show changes over timescales of only a few days. The most dynamic feature in the inner part of the nebula is the point where the pulsar’s equatorial wind slams into the bulk of the nebula, forming a shock front. The shape and position of this feature shifts rapidly, with the equatorial wind appearing as a series of wisp-like features that steepen, brighten, then fade as they move away from the pulsar to well out into the main body of the nebula.
Video
Details:
All data is from the Hubble proposals #13109, #13196, #13348, #13510, #13751, #13772, #14329
In order, the dates of the 16 frames are as follows:
- 2013-2-24
- 2013-4-14
- 2013-8-13
- 2013-12-01
- 2014-1-20
- 2014-4-13
- 2014-8-10
- 2014-8-21
- 2014-11-16
- 2015-1-21
- 2015-4-16
- 2015-8-12
- 2015-11-1
- 2016-1-22
- 2016-4-13
- 2016-8-7
Processing:
All processing was done in pixinsight and DaVinci resolve
- Subframes were star aligned
- Subframes were cropped
- Subframes were batch linear fit to the first subframe
- Batch stretch
- Batch LHE
- Batch Sharpening
- Timelapse assembly was done in davinci resolve