Hubble Image: Star comparison

I was just admiring the Glactic Fountain of Youth NGC 5775 When I noticed that a few of the closer stars looked very similar in appearance. Use the zoomable feature on the page and check out the whole galaxy, it is amamzing, but the rings aroud those stars kinda baffle me.


The first image is an image overlay using the "Multiplier" layer filter, which means it makes similar colored pixels in each image more pronounced. not exact but interesting to show them all together.
[atsimg]http://files.abovetopsecret.com/images/member/4023b5aa12ae.jpg[/atsimg]

reply to post by BornParadox


I think thats just an optical effect. Stars of a certain size and brightness will tend to look the same when looked at through the same telescope since there is little visual data anyway...basically just a bright dot. The crosses and circles seen are similar to lens flare effects, and have to do with the internal optics of the telescope used.

reply to post by bhornbuckle75


yeah.. check out the hubble mirror. It has indentations right where the bright spots are showing up around the central star exposure. Didn't know there was a central plate, whatever its purpose is. Those rings around the larger one are still really curious thou.. why is it showings rings?

Beautiful! I wonder it's authenticity

very beautiful images, i think the difference in them are to do witht he actual telescope though

reply to post by BornParadox


Good find friend! Yeah that's exactly the kind of stuff that can get reflected around inside the glass of the lens. Smaller cameras do it too. That would always bother me when I'd see a UFO video...which may have in fact been mysterious in and of itself, but then the video would zoom in past the focus range of the lens and suddenly you'd see some odd shape which people unaware of the phenomena suddenly assume is the actual shape of the UFO. Having ran cameras both as a hobby and professionally for a large part of my life I can recognize such shapes as just artifacts caused by lens reflecting the internal mechanisms of the particular camera.

As far as the circles go in these photographs....I do suppose it could be something physical....for instance some gas/particle cloud surrounding the star in an orbit of it. Still I think I'd imagine its more likely another optical effect....I'm sure I've seen it before in more mundane images...for instance before posting this reply I did a really quick Google search looking for Street Lamp pictures...hopping to find one with the ring effect. Unfortunately I didn't (like I said though...I only looked for about 5 minutes or so...given more motivation I'm pretty confident I'd find a picture very similar) Maybe someone out there with a bit more time, can find one and post it here.

The rings are called diffraction rings. They arise due to the fact that diffraction limits the smallest size a point of light can be focused to by a circular aperture. This is called the Airy disk.

The bright spikes are called diffraction spikes, and are caused by the support trusses that hold the secondary mirror in place.

reply to post by nataylor


Hot damn man.. Thanks for helping me piece the puzzle together.