Starship Asterisk*

and imagine how big this really is when you know New Horizons is 4.5+ light hours away and took 9 years to get there on a " fast rocket " and this structure is 10 LY wide in one dimension. It is going to take a few Santa Maria " voyages of discovery and some really wealthy Spanish queens

[quote="Chris Peterson"]Lord Rosse, who named the Crab nebula based on an initial observation, couldn't even manage to see it that way in subsequent observations![/quote]

Maybe he'd been seeing his eyelashes as I usually do the first time out.

People might be interested in a version of the crab I did in June of the visible portion of the Crab in mediumband green by Hubble. it was artificially colored to add visual interest only. It is one of those things I think is very interesting to compare to the available narrowband imagery.
[url=https://flic.kr/p/vPng5Z][img]https://farm1.staticflickr.com/337/19570369685_cf6828a3bb.jpg[/img][/url]

[quote="quigley"]Are the thousands of pillars visible in the image the same as those we see in star forming regions of nebulae?[/quote]
No. These are filaments of gas and dust that are dispersing. Star forming regions are in the process of collapsing and coalescing- just the opposite of what's happening here.

Are the thousands of pillars visible in the image the same as those we see in star forming regions of nebulae?

I was traveling thru the farm country in eastern Washington last year and I saw a farmer running his manure spreader behind his tractor. This is the cosmological equivalent.

[quote="George Dunbar"]Does the image of the Crab Nebula show any significant (visible) change during the passage of weeks, months or years?[/quote]

In addition to the expansion and gradual changes in outer filaments shown in that caparison, there are much faster changes due to the pulsar wind very close to it - [url=http://chandra.harvard.edu/photo/2002/0052/animations.html]here[/url] is a comparison of Hubble and Chandra time-lapse sequences.

The nebula is noticeably smaller in the first published photographs taken about a century ago now. When Messier found it, it was only about 3/4 of its present size and may have been rather brighter (weasel words because it's unusual among supernova remnants in shining largely from pulsar spindown rather than cooling of the explosion debris as such).

[quote="George Dunbar"]Does the image of the Crab Nebula show any significant (visible) change during the passage of weeks, months or years?[/quote]
Here's an animation comparing 1999 to 2012, by Adam Block.

[vimeo]https://vimeo.com/71117055[/vimeo]

Does the image of the Crab Nebula show any significant (visible) change during the passage of weeks, months or years?

[quote="Steve Dutch"]To me, this looks nothing like a crab. Maybe a sea slug. The Orion Nebula looks far more like a crab, with the central bright area the carapace and the two outer arms the claws.[/quote]
Virtually none of the long-named astronomical objects look like their namesakes when observed by the HST (or any high resolution imager). The pareidolia involved in deciding those names depends upon interpreting a fuzzy gray spot in a telescope eyepiece. Does the bunny you see in a cloud still look like a bunny when you can examine the cloud droplet by droplet?

(Lord Rosse, who named the Crab nebula based on an initial observation, couldn't even manage to see it that way in subsequent observations!)

To me, this looks nothing like a crab. Maybe a sea slug. The Orion Nebula looks far more like a crab, with the central bright area the carapace and the two outer arms the claws.

Always such an awesome sight....

:---[===] *

Surprised I can't find the pulsar! (Long, long, ago I was, for just half an hour, the only person in the world who knew that the X-rays from Crab pulsed! Then I phoned a colleague and told him that my Fourier-analysis had found a signal.)

[url=http://apod.nasa.gov/apod/ap150816.html][img]http://apod.nasa.gov/apod/calendar/S_150816.jpg[/img] [size=150]M1: The Crab Nebula from Hubble[/size][/url]

[b]Explanation:[/b] This is the mess that is left when a star explodes. The [url=http://messier.seds.org/more/m001_h2.html]Crab Nebula[/url], the result of a [url=http://imagine.gsfc.nasa.gov/science/objects/supernovae1.html]supernova[/url] seen in [url=http://messier.seds.org/more/m001_sn.html]1054 AD[/url], is filled with [url=http://www.youtube.com/watch?v=5VnJ9pRR8-8]mysterious[/url] filaments. The [url=http://apod.nasa.gov/apod/ap980208.html]filaments[/url] are not only tremendously complex, but appear to have [url=http://adsabs.harvard.edu/abs/1995ApJ...454L.129F]less mass than expelled[/url] in the original supernova and a [url=http://adsabs.harvard.edu/abs/1998PASP..110..831N]higher speed than expected[/url] from a free explosion. The [url=http://hubblesite.org/newscenter/archive/releases/2005/37/]featured image[/url], taken by the [url=http://apod.nasa.gov/apod/ap950810.html]Hubble Space Telescope[/url], is presented in three colors chosen for [url=http://s9.favim.com/orig/131225/cat-galaxy-glasses-Favim.com-1181244.jpg]scientific interest[/url]. The [url=http://en.wikipedia.org/wiki/Crab_Nebula]Crab Nebula[/url] spans about 10 [url=http://starchild.gsfc.nasa.gov/docs/StarChild/questions/question19.html]light-years[/url]. In [url=https://www.youtube.com/watch?v=vPxLVgTIAbk]the nebula[/url]'s very center lies a [url=http://www.jb.man.ac.uk/~pulsar/Education/Sounds/sounds.html]pulsar[/url]: a [url=http://www.astro.umd.edu/~miller/nstar.html]neutron star[/url] as massive as the [url=http://en.wikipedia.org/wiki/Sun]Sun[/url] but with only the size of a [url=http://www.cityofhoughton.com/]small town[/url]. The [url=http://apod.nasa.gov/apod/ap020920.html]Crab Pulsar[/url] rotates about 30 times each second.

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