Starship Asterisk*

Also isn't there a theory that the Pencil Nebula is a separate supernova remnant?

[quote="Ann"][quote="DavidLeodis"]The following annotated link shows well the Pencil Nebula's location in the Vela Supernova Remnant [url]http://apod.nasa.gov/apod/image/0803/VelaMosaicLabels_gendler1200.jpg[/url][/quote]

Thanks! That image gives us a very good idea of the size, brightness and color of the Pencil Nebula compared with the rest of the Vela supernova remnant.

By the way, the brilliant star designated Dun 65 is the well-known O + Wolf Rayet star [url=http://stars.astro.illinois.edu/sow/regor.html]Gamma-2 Velorum[/url].

Ann[/quote]
An updated labeled version is [url=http://www.robgendlerastropics.com/VelamosaicLabels.html]here[/url].

[quote="DavidLeodis"]The following annotated link shows well the Pencil Nebula's location in the Vela Supernova Remnant [url]http://apod.nasa.gov/apod/image/0803/VelaMosaicLabels_gendler1200.jpg[/url][/quote]

Thanks! That image gives us a very good idea of the size, brightness and color of the Pencil Nebula compared with the rest of the Vela supernova remnant.

By the way, the brilliant star designated Dun 65 is the well-known O + Wolf Rayet star [url=http://stars.astro.illinois.edu/sow/regor.html]Gamma-2 Velorum[/url].

Ann

Wow Dave Jurasevich is the guy that discovered the Soap Bubble Nebula! :shock: :clap:

The following annotated link shows well the Pencil Nebula's location in the Vela Supernova Remnant [url]http://apod.nasa.gov/apod/image/0803/VelaMosaicLabels_gendler1200.jpg[/url]

If you zoom in to the 12:30 position there Is the appearance of a Double star (Brighter on top). Just below this appears to be a Screaming Specter ala [url=http://www.edvardmunch.org/the-scream.jsp]Edvard Munch[/url] though this scream is having a bright idea

If you click on the picture, or zoom out a bit, it looks like an "angel" on a surfboard....

Really nice image.
:---[===] *

[quote="Velligis"]Anyone else think this looks a little like the nexus from [i]Star Trek: Generations[/i]?[/quote]

I was looking at the bright star in the top right and wondering why they have a picture of my wife using a lectern while three bearded gentlemen from the Victorian-era Royal Society listen to her lecture.

Not that she ever did.

Or would.

Anyone else think this looks a little like the nexus from Star Trek: Generations?

[quote="RocketRon"]Would you actually get a 'shock wave' in the vacuum of space ?
Or is this a simplification - of something ?

And, why would it slow ?
How do we know it slowed ?

Its what's not said that is often the interesting stuff....[/quote]

[float=left][img]http://cache4.asset-cache.net/xd/487239118.jpg?v=1&c=IWSAsset&k=2&d=DF8D445051B40C74DE1AAE2E3B00B553DD9BE2D9A1DB104C94F71DDAA6ADA1EB2E9ED959007B0637[/img][c][size=75]Car driving in snowfall. Photo: http://www.gettyimages.com/detail/video/car-driving-at-night-on-snowy-road-in-snowfall-stock-footage/487239118
[/size][/c][/float] [float=right][img]https://www.angieslist.com/files/styles/adslider_full/public/chicagosnowplowtheft.png?itok=b6cz4jks[/img][c][size=75]Snow plow piling up snow.
Source: https://www.angieslist.com/articles/chicago-area-snow-plow-thefts-pile.htm[/size][/c][/float]














Just because the interstellar medium is extremely rarefied doesn't mean it is a "true" vacuum.

Wherever you have a nebula in space, whether it is an emission or a reflection nebula, there are ions emitting light or dust particles reflecting light. Sometimes both phenomena occur simultaneously.

A reflection nebula in space is basically the same thing as the light from a car's headlights being reflected by the snowflakes of a heavy snowfall. We can pile up snow and make snow piles.

Interstellar dust is slightly similar to snow, in that it is made of tiny grains of dust coated with ice. Interstellar dust, with its associated hydrogen gas, [i]can[/i] be piled up. And while there are no snowplows in space, there are hot stars with terrific stellar winds, and there are shock waves remnants of supernova explosions.

Ann

Would you actually get a 'shock wave' in the vacuum of space ?
Or is this a simplification - of something ?

And, why would it slow ?
How do we know it slowed ?

Its what's not said that is often the interesting stuff....

The tour provided by Dave Jurasevich of the Las Campanas Observatory was especially interesting. Thanks for the tour, Dave. Nice job.

Are you certain it is not a manifestation of The Flying Spaghetti Monster ?

[url=http://apod.nasa.gov/apod/ap160715.html][img]http://apod.nasa.gov/apod/calendar/S_160715.jpg[/img] [size=150]NGC 2736: The Pencil Nebula[/size][/url]

[b] Explanation: [/b] Moving from top to bottom in the frame near the center of this [url=http://starimager.com/Image%20Gallery%20Pages/%20Hydrogen%20Alpha%20Images/ngc%202736%20NB%20bi%20color_LCO%20AP12MC_1250.html]sharply detailed color composite[/url], thin, bright, braided filaments are actually long ripples in a cosmic sheet of glowing gas seen almost edge-on. The shock wave plows through interstellar space at over 500,000 kilometers per hour. [url=http://heritage.stsci.edu/2003/16/supplemental.html]Cataloged as NGC 2736[/url], its elongated appearance suggests its popular name, [url=http://www.nasa.gov/vision/universe/starsgalaxies/pencil_nebula.html]the Pencil Nebula[/url]. The Pencil Nebula is about 5 light-years long and 800 light-years away, but represents only a small part of the [url=http://violet.pha.jhu.edu/~wpb/hstvela/hstvela.html]Vela supernova remnant[/url]. The [url=http://apod.nasa.gov/apod/ap080306.html]Vela remnant itself[/url] is around 100 light-years in diameter, the expanding [url=http://chandra.harvard.edu/xray_sources/supernovas.html]debris cloud of a star[/url] that was seen to explode about 11,000 years ago. Initially, the shock wave was moving at millions of kilometers per hour but has slowed considerably, sweeping up surrounding interstellar material. In the narrowband, wide field image, red and blue-green colors track the characteristic glow of [url=http://apod.nasa.gov/apod/ap051223.html]ionized hydrogen[/url] and [url=http://apod.nasa.gov/apod/ap130307.html]oxygen atoms[/url].

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