Starship Asterisk*

The Belt of Venus illustrates this. The upper pink part is directly lit by the Sun. The lower blue part is only scattering light from other parts of the sky. Regarding the lower blue part, which is the Earth's shadow, I wonder if the blue color is not a function of Rayleigh scattering but instead C...

The link to the "webda" page mentioned (https://webda.physics.muni.cz/cgi-bin/ocl_page.cgi?dirname=ngc2169) shows a "Log age" of 7.067 and 10 the power of that is about 11,668,096.17 😊 That's because you have a cheap calculator. Mine has more digits, so I know the age of this cl...

Log Age What about it? The link to the "webda" page mentioned (https://webda.physics.muni.cz/cgi-bin/ocl_page.cgi?dirname=ngc2169) shows a "Log age" of 7.067 and 10 the power of that is about 11,668,096.17 😊 That's because you have a cheap calculator. Mine has more digits, so I ...

LOG Age = 7.067 means 10^^7.067, which on my Casio shows 11,668,096. No, it means "about 11 million years". Or maybe, "about 11.5 million years". All but the first few digits are insignificant, and when you write them out it results in a misleading number, that might fool somebo...

Roy wrote: ↑Tue May 14, 2024 6:09 pmLog Age

What about it?

The color green does not exist outside our human eyes and brains. It is our eyes and brains that "create" the color green. Also then should be the case regarding the sun's green flash, it is an optical phenomenon, as our eyes and brains also create the color green of the sun's green flash...

I wonder if this Wikipedia article on Sky brightness makes sense -- it seems to that there is both direct and indirect sunlight in the sky at twilight -- "Indirectly scattered sunlight comes from ... the atmosphere itself .... the Sun has just set but still illuminates the upper atmosphere dir...

Hopefully someone can clear up some sun confusions for me. Today's APOD shows AR-3664 towards the BOTTOM of the solar disk. That of May 11 showed this cluster to be towards the RIGHT. Does the apparent orientation of the sun shift from day to day? My understanding is that the storms move from left ...

The color green does not exist outside our human eyes and brains. It is our eyes and brains that "create" the color green. Also then should be the case regarding the sun's green flash, it is an optical phenomenon, as our eyes and brains also create the color green of the sun's green flash...

Nowhere in the information supplied do they mention the classification or number of the stars in the cluster. Yet the age of the cluster is estimated to be only 11,668,000 years. Curiously short - and no leftover nebular material. About 30 stars. The cluster does lie inside a region of faint nebulo...

The write-up mentioned that our Sun may have been part of a cluster at one time. Do we know where our sun was born? Was that theoretical cluster here, or did the Sun migrate to here from 'parts unknown'? Do astronomers have any theories of as to where our cluster was? The cluster that the Sun forme...

Nowhere in the information supplied do they mention the classification or number of the stars in the cluster. Yet the age of the cluster is estimated to be only 11,668,000 years. Curiously short - and no leftover nebular material. About 30 stars. The cluster does lie inside a region of faint nebulo...

Hopefully someone can clear up some sun confusions for me. Today's APOD shows AR-3664 towards the BOTTOM of the solar disk. That of May 11 showed this cluster to be towards the RIGHT. Does the apparent orientation of the sun shift from day to day? My understanding is that the storms move from left ...

We are getting alot of photoshopped pictures . What do I mean? In this case, a picture of the sunspots superimposed on the sun in a photo in which the sun would be too bright to look at, to cause an artistic view. Photo or portrait? It's an HDR image, composited from several different exposure time...

Rauf wrote: ↑Mon May 13, 2024 8:10 am So is it 3664 or 6443?

AR 3664.

Last night I tried to photograph the aurora with my DSLR with little success. My wife took these with her IPhone. image_123650291 (1)a.JPG image_123650291 (2)a.JPG image_123650291a.JPG With my eye it was not very apparent but her cell phone captured quite a different scene. :? Is aurora photography...

It works but only if the youtube url is of a specific format, namely like this: https://www.youtube.com/watch?v=1MYJhsjX-C4 And you need to use the right tags: [youtube][/youtube] The result looks like so: https://www.youtube.com/watch?v=1MYJhsjX-C4 I wonder why after I clicked Show in YouTube I wa...

Is this image, its quality and the gesture to publish it, a huge joke? From time to time APOD editions pop into my view, last time I left some abrasive comments was for the photoshoped solar eclipse-moon-something. I literally shoot better (read: much better, link below to our forum) images during ...

And where were they? Is it ever possible to link a specific sunspot group with an aurora? The four CMEs in the last days, and the new one today, all came from this group, and are responsible for the current auroral activity. Ok. Is the cause and effect indisputable? I guess so simply due to travel ...

Ok, where are the sunspots? 😊 Wrong question. Cause and effect. Where were the sunspots a couple of days ago? That's what mattered! And where were they? Is it ever possible to link a specific sunspot group with an aurora? The four CMEs in the last days, and the new one today, all came from this gro...

Pretty good here in central Colorado, 38°N, despite it being pretty cloudy. This is an allsky video from late twilight to 1:30am when it completely clouded over. https://vimeo.com/945334892 Last image below was taken pointing very high, with the Big Dipper in the frame. _ E7_48521p.jpg E7_48527p.jp...

Pretty good here in central Colorado, 38°N, despite it being pretty cloudy. This is an allsky video from late twilight to 1:30am when it completely clouded over. https://vimeo.com/945334892 Last image below was taken pointing very high, with the Big Dipper in the frame. _ E7_48521p.jpg E7_48527p.jpg...

How can evolution favor an organism's death? In the big picture, no species can evolve for long if the old versions aren't eliminated. You need reproduction for adaptation and evolution, and you can't have reproduction without death in any system with limited resources. OK, let's say that hypotheti...

Yes, but why a tree can't live forever? I mean, some have been living for more than a millennia. Why this tree can't live that long? DNA gets damaged over time, toxins accumulate over time. Some pest, parasite, or disease will eventually win. And evolution doesn't favor organisms that don't die and...

Earth is sweeping up “particles” - charged, by the way - from solar flares. What charged particle? Electrons & protons - electricity. Now we get to see if it sis another Carrington event. My thought is: probably not, because there are a lot more wires and a lot more grounds than there were in 1...