Welcome toAtheist Universe
Sign Upor Sign In
Or sign in with:
We are a worldwide social network of freethinkers, atheists, agnostics and secular humanists.
Give a Gift
Give a Gift
Give a Gift
Give a Gift
Give a Gift
Cosmology Astrophysics Astronomy
Latest Activity: on Monday
Cosmology - Astrophysics - Astronomy
Hubble Wallpaper - Awesome Hubble Images
Started by Tom Sarbeck. Last reply by Tom Sarbeck Jul 23, 2017.
Started by Mrs.B. Last reply by Mrs.B Apr 9, 2016.
Started by Davy. Last reply by Onyango Makagutu Mar 8, 2016.
Started by Davy Oct 3, 2013.
Started by Davy. Last reply by Davy Aug 15, 2013.
A dark star is a theoretical type of star that may have existed early in the history of the universe before conventional stars were able to form. They would be composed mostly of normal matter, like modern stars, but a high concentration of neutralino dark matter within them would generate heat via annihilation reactions between the dark matter particles. This heat would prevent them from collapsing into the relatively compact sizes of modern stars and therefore prevent nuclear fusion among the normal matter atoms from being initiated.
Under this model, a dark star is predicted to be an enormous cloud of hydrogen and helium ranging between 4 and 2000 astronomical units in diameter and with a surface temperature low enough that the emitted radiation would be invisible to the naked eye.
It is possible that dark stars have endured to the modern era. Although they would emit no visible light they could be detectable by their emissions of gamma rays, neutrinos, and antimatter and would be associated with clouds of cold molecular hydrogen gas that normally wouldn’t harbor such energetic particles.
No, this was was extraordinary because of the sun storm that happened last Saturday, it made it visible from much lower latitudes than usual. And i missed it :-(
now, i am wracking my brain to remember what time of night that was, and i've been going outside every hour or two, to try to see one again. THe one i saw, didn't last very long at all, no idea how long it had been there prior to my noticing it,
but, it only lasted about 10 or 15 minutes after i did see it,
til it faded away, was only barely perceptible after that.
Is this something that we can try to look for EVERY October, then? sounds like it, by the article. Yet another reason to love fall, i guess!
It's great to got to see this, JM!! No chance here in NYC! Check out my Weekly Science Fix (blog) for a link to more images. And do not miss the video "The Mountain"
I SAW THIS! I SAW THIS!! JUST THE OTHER NIGHT, two nights ago, maybe. Flipped right out! what a shock! what an awesome breathtaking surprising sight! I"d never ever seen them here before!!
the one i saw, was psychedelic pink, magenta, and silver........WOW AND WOW!!
I was out walking the dog, and it caught my eye immediately, it was HUGE, covered half the sky, and was sort of undulating a bit, too.
I ran back home, made my family wrap up in blankets and throw on shoes to come out to see it. They didn't really feel like it, but i insisted. They were amazed, and really stoked, it WAS something to behold...
wow..............SO GLAD YOU POSTED THIS, DOONE, i had been meaning to investigate to see what that WAS!!?? OR rather, WHY, after all these years, i am now seeing aororas HERE in THIS town!!?!
I did recognize them, having only seen them THAT dramatically in photos before, but, i had no idea WHY i can NOW see them here....cool!!!
Explanation: As northern hemisphere nights grow longer, October is a good month for spotting auroras, or even other eerie apparitions after dark. And this week the night sky did not disappoint. On October 24th a solar coronal mass ejection impacted planet Earth's magnetosphere triggering far ranging auroral displays. On that night, this dramatic silhouette against deep red and beautiful green curtains of shimmering light was captured near Whitby, Ontario, Canada. But auroras were reported even farther south, in US states like Alabama, Kansas, and Oklahoma at latitudes rarely haunted by the northern lights. Well above 100 kilometers, at the highest altitudes infused by the auroral glow, the red color comes from the excitation of oxygen atoms.
Check-out the series of really fantastic lightning pictures here.
The Saturn neighborhood is simply awesome.
Explanation: A fourth moon is visible on the above image if you look hard enough. First -- and farthest in the background -- is Titan, the largest moon of Saturn and one of the larger moons in the Solar System. The dark feature across the top of this perpetually cloudy world is the north polar hood. The next most obvious moon is bright Dione, visible in the foreground, complete with craters and long ice cliffs. Jutting in from the left are several of Saturn's expansive rings, including Saturn's A ring featuring the dark Encke Gap. On the far right, just outside the rings, is Pandora, a moon only 80-kilometers across that helps shepherd Saturn's F ring. The fourth moon? If you look closely in the Encke Gap you'll find a speck that is actually Pan. Although one of Saturn's smallest moons at 35-kilometers across, Pan is massive enough to help keep the Encke gap relatively free of ring particles.
Explanation: What created the Waterfall Nebula? No one knows. The structure seen in the region of NGC 1999 in the Great Orion Molecular Cloud complex is one of the more mysterious structures yet found on the sky. Designated HH-222, the elongated gaseous stream stretches about ten light years and emits an unusual array of colors. One hypothesis is that the gas filament results from the wind from a young star impacting a nearby molecular cloud. That would not explain, however, why the Waterfall and fainter streams all appear to converge on a bright but unusual non thermal radio source located toward the upper left of the curving structure. Another hypothesis is that the unusual radio source originates from a binary system containing a hot white dwarf, neutron star, or black hole, and that the Waterfall is just a jet from this energetic system. Such systems, though, are typically strong X-rays emitters, and no X-rays have been detected. For now, this case remains unsolved. Perhaps well-chosen future observations and clever deductive reasoning will unlock the true origin of this enigmatic wisp in the future.
© 2018 Created by Atheist Universe.
Report an Issue |
Terms of Service
Please check your browser settings or contact your system administrator.