Suggested topics for Space.com articles

Is there a thread of some kind that allows topic suggestions for the great writers here at Space.com?

Some folks here may have some unique experiences and knowledge worth offering.
 
To my knowledge, there is no formal paper on the Sun’s true color — defined as the color we would see of the solar disk when viewed from above our atmosphere and properly attenuated. I doubt there needs to be a paper, to be fair.

My avatar is an image from the McMath-Pierce solar observatory that demonstrably falsifies the yellow hypothesis that became incredibly ubiquitous.

Also, how it became “yellow” is quite a story born out of early stellar spectroscopy by Rutherford, Secchi and others.
 
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Helio, FYI. I view the Sun regularly using my 90-mm refractor with glass, white light solar filter that fits on the dew cap in front of the telescope optics. Common observations range 30x to 70x or so in my stargazing log I keep. I viewed the Sun seven times in June (6th-16th), observing sunspot AR2765 reported at spaceweather.com. When I see the Sun, at 0800 the Sun appears somewhat yellow with tint of slight orange around the limb. Later viewing the Sun near 1400 EDT, much higher elevation angle and the Sun appears more white with slight tint of yellow around the limb. I do not observe using H-alpha filter though. However, this is not solar observing *above our atmosphere* :)
 
rod, have you ever projected the solar image on a white or "gray" card? If not, just do a 2mm diameter hole in a card and allow sunlight to project the image. For a higher altitude Sun, you won't see any yellow, though by diffraction at the edge, perhaps you will. Refractors and especially filters will change the color. The limb coloring you note is because of the CLV (Center to Limb Variation). The limb temperature is that of the upper photosphere and it is cooler (5000K) whereas the lower region of the photosphere is seen when viewing the central region (6,390K) -- that's a lot of temperature difference. Yet even a 5000K blackbody doesn't produce a yellow result unless an atmosphere or filter is used.

I think the Baader filters give a white Sun, except near the horizon. My filter also gives a yellow results.
 
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I thought there was a thread about suggested topics already, but I haven't been able to find it. As for moving comments to new threads, that is not something we can do. We could rename THIS thread, but I think you could as well.

Wolfshadw
Moderator

Edit: It was a Question of the Week thread

-Wolf sends
I have started a new thread... The True Color of the Sun

Hopefully, this will move the discussion there and restore the purpose of this thread.
 
Shill that I am....

A full article on the first successfully light communications from Earth to someone in space, including the use of a blue laser, was accomplished by the San Antonio Astronomy Assoc. in 2012. Astronauts Don Pettit and Dan Burbank on the ISS received and imaged light signals that came from a small observatory. It was Don that developed the camera imaging system that would allow nighttime imaging.

The whole story was never told but snippets were found on many blogs. It was Don's interest in astrophotography that connected him to Robert Reeves, an author of about 1/2 dozen books, primarily in astrophotography. They decided it would be great to try it, though others had tried but failed, apparently. There were challenges including the fact that astronauts operate on GMT, so their fly-over was 1am their time, affecting NASA's schedule.

The Atlantic picked up the story back then.
 
It would be cool if there was a quiz thread asking some unique questions, like what the peak color of the Sun emissions really are -- based on both the energy vs. wavelength, and photon flux density vs. wavelength. The results are different colors. You could also ask what the peak color is using a blackbody equation (Wien's law).
 
The recent article on Betelgeuse reminds me of a few predicted signs we may be able to look for just prior to it going supernova. But they were forum speculations.

Are there some expected observations that would cut the 100k year time frame to, say, 100 years?

I would bet most signs would each have their own time-till-blowing. A huge neutrino burst, for example, would cut that 100k years down to a couple of seconds. :)
 

Catastrophe

"There never was a good war, or a bad peace."
"The world's largest International Dark Sky Reserve is coming to Texas and Mexico, thanks to a partnership between The University of Texas at Austin's McDonald Observatory, The Nature Conservancy, the International Dark-Sky Association (IDA) and many others. The designation, granted by the IDA, recognizes the commitment of organizations, governments, businesses and residents in the region to maintaining dark skies. The move will benefit not only astronomical research, but also wildlife, ecology and tourism."

Cat :)
 
"The world's largest International Dark Sky Reserve is coming to Texas and Mexico, thanks to a partnership between The University of Texas at Austin's McDonald Observatory, The Nature Conservancy, the International Dark-Sky Association (IDA) and many others. The designation, granted by the IDA, recognizes the commitment of organizations, governments, businesses and residents in the region to maintaining dark skies. The move will benefit not only astronomical research, but also wildlife, ecology and tourism."
Indeed. McDonald Obs. has the darkest skies of all the US mainland major observatories. But the growth in the oil field work prompted action. I don't know the whole story, but our local (San Antonio) club became aware of the effort (especially Bill Wren) and a few of us got involved, including writing letters explaining that a simple rule or two would make greatly limit light pollution and also provide more light on the ground for the users. Thus, it was a simple change in fixture design that reflects all the light downward rather than most the light.

Bill Wren is quite a story in himself. He designed a special telescope to allow wheel-chaired observers, and I think it's aperture is about 16". In the early 1990s, there was a great hunt for SN to help determine Ho, so with his smaller telescope he observed galaxies as they were near the meridian. [Herschel did the same thing with his big scope.] His regular nightly effort allowed him to memorize their locations so he was able to cover a lot of galaxies each night.
 
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