Why do the bright stars appear to have four points?

sheilab8 · Post by **sheilab8** » Mon Aug 09, 2010 10:16 pm

Why do the bright stars appear to have four points in the photographs? Is it an effect of the telescope or camera?

neufer · Post by **neufer** » Mon Aug 09, 2010 10:32 pm

sheilab8 wrote:Why do the bright stars appear to have four points in the photographs? Is it an effect of the telescope or camera?

It is not uncommon to use four struts to secure the secondary mirror:

owlice · Post by **owlice** » Mon Aug 09, 2010 10:43 pm

Sheila, welcome to Asterisk! Yes, they are from the telescope. They are called diffraction spikes, and more information about them can be found in this Wikipedia article.

BMAONE23 · Post by **BMAONE23** » Tue Aug 10, 2010 2:39 am

They can also be utilized to point out some near by binary stars as these could have split diffraction spikes
similar to Pluto/Charon

http://www.google.com/imgres?imgurl=htt ... CCYQ9QEwAw

neufer · Post by **neufer** » Tue Aug 10, 2010 3:07 am

http://antwrp.gsfc.nasa.gov/apod/ap010415.html

BMAONE23 wrote:
[size=175][color=#0000FF]4-vane spider, 3-vane spider, etc.[/color][/size]

"The code" is so "vane" he probably thinks those "spiders" are about him.

Starship Asterisk*

Why do the bright stars appear to have four points?

Why do the bright stars appear to have four points?

Re: Why do the bright stars appear to have four points?

Re: Why do the bright stars appear to have four points?

Re: Why do the bright stars appear to have four points?

Re: Why do the bright stars appear to have four points?