User talk:John187

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Greetings!

There is a "welcome" page which new users get. It gives the new user some friendly hints, and so on. It looks like yours hasn't arrived yet.

You just made some additions to the Supernova page. And there is one paragaph that I suspect is either incorrect or unclear. You wrote:

The core collapse phase is known to be extremely dense and energetic so only neutrinos are able to escape the collapsing star. Therefore, Supernovae release as many as several Solar masses of energy or more than joules, in a short 10 second burst of neutrinos. This quantity of energy is roughly equivalent to the output of the Sun over its entire lifetime.

You seem to be saying that the equivalent of a mass several times the mass of the sun is transformed into energy. You go on to say that this is roughly equivalent to energy output of the sun, over its lifetime.

Well Fusion is not that efficient. The Fusion of Hydrogen to Helium transforms only a small percentage of the mass of a star to energy. On the order of 1 percent IIRC. Certainly not several 100 percent.

Hopefully this note from me won't prevent you getting your friendly hints! -- Geo Swan 22:12, 2005 Mar 12 (UTC)


Thanks for the clarification but I think the misunderstanding stems from a lack of understanding of the SN core collapse phase. Most SN are occuring in stars of much larger than 1 solar mass, so releasing this much energy is no problem. A typical figure is 10^58 erg, which is several hundred solar masses worth of energy. A solar mass is more like 10^54 erg. I conservatively said "several solar masses" to prevent messages like this.

For all those who are curious about Supernovae there are many good astrophysical reviews in the literature:

http://arxiv.org/abs/hep-ph/0212326 http://arxiv.org/abs/hep-ph/9901300

Also, the statement about the total energy output of the sun was a part of the orig article which I preserved in my edit. I think it's a good benchmark for an average person to understand how much energy we are talking about.

Image Tagging Image:Wavepacket.png

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This image may be deleted.

Thanks for uploading Image:Wavepacket.png. I notice the image page currently doesn't specify who created the image, so the copyright status is therefore unclear. If you have not created the image yourself then you need to argue that we have the right to use the image on Wikipedia (see copyright tagging below). If you have not created the image yourself then you should also specify where you found it, i.e., in most cases link to the website where you got it, and the terms of use for content from that page.

If the image also doesn't have a copyright tag then you must also add one. If you created/took the picture then you can use {{GFDL}} to release it under the GFDL. If you believe the image qualifies as fair use, please read fair use, and then use a tag such as {{Non-free fair use in|article name}} or one of the other tags listed at Wikipedia:Image copyright tags#Fair_use. See Wikipedia:Image copyright tags for the full list of copyright tags that you can use.

If you have uploaded other images, please check that you have specified their source and copyright tagged them, too. You can find a list of image pages you have edited by clicking on the "my contributions" link (it is located at the very top of any Wikipedia page when you are logged in), and then selecting "Image" from the dropdown box. Note that any unsourced and untagged images will be deleted one week after they have been uploaded, as described on criteria for speedy deletion. Thank you. Admrb♉ltz (T | C) 23:56, 23 January 2006 (UTC)


Serpent Mound Image

Copied from User talk:Pollinator

Hi, I noticed you are the contributor of the main image in the Serpent Mound article. This image looks like a photo-manipulation. It is far too green and far over saturated. Can you check to ensure the version you uploaded is not a photo-manip and is in fact authentically what was recorded by your camera or that your camera was not in a setting to record a very saturated picture. I live in Ohio and it is defnly not this green ;) Perhaps you have a problem with the color profile calibration in your monitor?

If you don't have a more natural representation of the Serpent Mound, I can donate one of mine. Nature is beautiful, just as olive and drab as it really is. I think making it greener just makes it look false, not more esthetic. John187 20:08, 10 February 2007 (UTC)

No, the photo is not manipulated in any way. It was a crisp, clear day with very low humidity, which made the images vivid. It was only cropped slightly and resized. I think the criticism is grossly unjustified, and therefore somewhat insulting. If you want to add a drab image from a blah day, please feel free, but I defend this photo as accurate.
By the way, when you add a comment on a user talk page, please put it at the bottom. Pollinator 20:32, 10 February 2007 (UTC)