Speaking of Venus - On Saturday night (May 8th 2004) at about 9.30pm local time (2030Hrs UT)I could have sworn - in fact I did see the unusual sight of 'Ashen Light' - the sight of the unlit side of Venus.

I was using my 8" SCT at Mag x100 when I easily saw what I could only describe as a 40 arcsecond size disk/ball hanging in my field of view. The 'Darkside' of Venus was clearly visible as a dark brown coloured sphere, directly visible, not even hard to trace. I did'nt even need to use averted vision, the whole planet was clearly traceable, I could even make out the curve of the unlit portion
of the planet, I did'nt use any filters. The sky was still quite bright as the sun set at about 9:10pm. I choose this time as no to let the
light from the bright side of Venus to swamp the view.

I had to call my wife out to have a look, not saying anything, her reaction - OH! the Moon, it looks lovely - that's the earthshine is'nt it!!!!! Well - Independent observer No.1!

So, my question - Is this a rare sighting/or is this to be expected when Venus is this close?? Has anyone else seen this?
This was the 1st time I've ever seen this in 10 years of observing!
Keith..

Was at a talk by Prof. Fred Taylor from Oxford, and he mentioned that the Ashen light may be caused by the surface ov Venus being so hot that it glows, and its this glow that lights up the clouds.

Not so long ago this was thought not to exist!

Cheers,
~Al

Definitely seen it!, just like a 3 day old moon - just seemed further away and no craters
Keith..

Keith/Albert,
I was out observing Venus on the 7th of May between 10 and 10.30 and I thought I was seeing some sort of optical/mind illusion,as if I could make out the rest of the shape of Venus. I thought that the scientific community had dismissed this phenomena ???
Did the latest set of probes to Venus over ther last 10 years all but dismiss the Ashen lights ???

Some people are saying they have seen the Ashen Light of Venus before and after sunset. if you check the March 2001 edition of Sky and Telescope P101, it says the the ashen light of Venus can ONLY be seen well after sunset, what ye ae seeing is an optical illusion where by its disk appears slightly darker as the eye completes the circle of the crescent. In a truly dark sky the brilliance of venus will test any optical system, some refractors will show venus sorrounded by a violet fringe(false colour), they say the use of an occulting bar may help in seeing the ashen light by hiding the crecents glare.As the crescent really begins to thin look for an extension of the horns beyond the 180 degrees sector to which they are usually confined. The thick athmosphere actually reflects and channels light beyond the sunlit hemisphere

Hi,

Not sure about the evidence from recent observations Dave, but this paper from 1992 give a nice overview of the ashen light at various wavelengths. Appears to be written with amateurs in mind.

adsbit.harvard.edu/cgi-bin/nph-iarticle_...=1992raa..proc...43C

Cheers,
~Al

Speaking of Venus - On Saturday night (May 8th 2004) at about 9.30pm local time (2030Hrs UT)I could have sworn - in fact I did see the unusual sight of 'Ashen Light' - the sight of the unlit side of Venus.
I was using my 8" SCT at Mag x100 when I easily saw what I could only describe as a 40 arcsecond size disk/ball hanging in my field of view. The 'Darkside' of Venus was clearly visible as a dark brown coloured sphere, directly visible, not even hard to trace. Keith..

Hi Keith,

Congratulations! I've never seen the ashen light myself. Fred Price discusses this phonomenon in his book The Planet Observer's Handbook, describing the colour variously reported as grey or reddish but that Webb saw it as a brownish colour in 1878. Also, he says English planetary observer, Richard Baum, has observed the ashen light over a period of 35 years, describing it as coppery, deep purple, olive or even rusty brown. So, your observation of a dark brown coloured sphere fits in with previously reported colour.

Gordon

Merging this with the posters other message in another thread to keep the transit thread clean - albertw

Venus, ashen light as a faint glow occasionally observed on the dark side of Venus, was first reported by Riccioli in 1643.

Ever since then, it seems that nearly all natural forms of such illumination have been ruled out, at least for the past 300 years and counting there's not been a viable alternative to those illuminations being other than artificially generated.

Utilizing a band-pass filter of 400~450 nm should offer the most bang for the buck/euro, although a more specific filter should only improve upon those observations, and of a recording whatever might be encoded within that spectrum of photons might be even a little more interesting, to say the least.

However folks, expecting any of these pretentious astronomy types to place their warm and fuzzy stamp of approval upon the notion that Venus could be harboring other life NOT as we know it, apparently this isn't an option, though of having humanity wasting more decades and trillions of dollars is worth every penny, especially if those pennies are going into their institution or better yet into their own pocket, meanwhile the polluting of mother Earth and of the pillaging for energy resources to a fairlywell, along with all of the collateral carnage, is just fine and dandy.

God forbid that we should consider upon the obvious prospects or perhaps fact of the matter that Venus isn't quite so darn hot and nasty, nor insisting that of sufficiently smart folks couldn't have managed to have coexisted in spite of our arrogance, greed and utter stupidity.

Ashen lights of Venus have been simply too well noticed, and of various radio astronomy and by way of numerous other instruments (other than photon detections) have not established upon any other natural source for their existence. That's sort of duh-101 for those illuminations being of pure photons which thereby obviously had to be created from the surface or perhaps from aboard some high flying rigid airship cruising quite safely and calm just below those nasty clouds.

The rigid airship notion as for providing a suitable platform by which to operate at perhaps 25+km shouldn't be ruled out. Even the notion of such rigid airships being capable of their cruising above them relatively cool nighttime clouds isn't outside the box of accepted physics-101.

BTW; I have another page or two to offer, but I do need and would appreciate your input:
guthvenus.tripod.com/earthshine-moonshine.htm
guthvenus.tripod.com/illumination-spots.htm
guthvenus.tripod.com/gv-hot-spots.htm

Sorry if you're a devout pro-NASA or more unfortunately a pro-Apollo sport, like I was as of prior to more than three years ago, thoroughly snookered to the hilt and all, and then some.
_________________
Regards, Brad Guth 1-253-8576061
guthvenus.tripod.com/index.htm

Well guess what Dave Lillis and other nice folks, that "very dark purple hue" is perhaps the 425 nm spectrum that's best suited at taking advantage of the opacity of them acidic clouds, and that's a fact. At least of anything below 450 nm isn't all that much in competition with earthshine.

Utilizing a band-pass filter of 400~450 nm should offer the most bang for the buck/euro, although a more specific filter should only improve upon those observations, and of a recording whatever might be encoded within that spectrum of photons might be even a little more interesting, to say the least.

BTW; I have another page or two to offer:
guthvenus.tripod.com/earthshine-moonshine.htm
guthvenus.tripod.com/illumination-spots.htm
guthvenus.tripod.com/gv-hot-spots.htm

Some interesting sites there, but I've yet to see a pic with definitive proof.

I went back to my pics and did all kinds of wonderful photoshop manipulation such as playing arounds with histograms/levels/filters/brightness/contract etc and checking the colour "number" with the surrounding background and could not get any variation in the area where the dark side of the globe would be, i.e. I wasnt able to find anything, and like I said earlier, the exposure was very low in those shots.

BUT, its going to be clear on Saturday/Sunday nights (according to the weather forecasts) and this time I'll see if I can hunt it down with the webcam.
Is this comparible to searching for the Martian Canals during the Mars opposition lat year ??? maybe.

BUT, its going to be clear on Saturday/Sunday nights (according to the weather forecasts) and this time I'll see if I can hunt it down with the webcam.
Is this comparible to searching for the Martian Canals during the Mars opposition lat year ??? maybe.

There are amateurs going to try taking spectroscopic measurements of venus during the transit, something should get absorbed in the clouds, and those lines should be detectable. Its a touch project, and not one that I have the equipment for but a challenge if you are interested.

Cheers,
~Al

Some interesting sites there, but I've yet to see a pic with definitive proof.

Check out the last image on www.vt-2004.org/photos/vt-photos-page8.html

Its in IR, but clearly shows the night side.

Cheers,
~Al

In order to help demonstrate that this form of Venus "ashen light" isn't hardly of earthshine, but certainly could have been artificially produced, I've run off some preliminary numbers that shouldn't surprise you, unless you're as thoroughly snookered and thereby as dumbfounded as most Americans, especially of those of our pro-Apollo or bust cult, and as such I'm reasonably certain that your math is even better than mine, as well as for uncovering the capable candela capability of xenon/mercury lighting cannons that could more than accommodate the task at hand.

Just for argument sake; if we'd started out with using a 500 meter diameter worth of illumination source, and if that source were initially focused to 1°, this is what we should expect such technology application to obtain as for transmitting into and subsequently getting photons through those clouds.

Illumination source elevation: 5 km
Illumination source diameter: 500 meters
Raw illumination divergence: 1°
Cloud bottom elevation at roughly: 50 km
Cloud density/thickness: 20 km
Illuminated zone/diameter upon cloud bottom: 1.286 km

Illuminated zone/diameter upon cloud tops:
At zero further divergence: 1.635 km
At +/- 45° divergence: 12 km
At +/- 60° divergence: 19 km
At +/- 75° divergence: 39 km
At +/- 80° divergence: 58 km
At +/- 85° divergence: 110 km
At +/- 90° divergence: 499 km

At a cloud plus haze depth of 25 km, it may take the +/- 85° through-pass divergence in order to obtain the exit illumination of 500 km diameter, such as that illumination viewed within the "heath4.jpg".

This is where physics-101 or perhaps physics duh-101 comes into account, in that I'd previously estimated upon the illuminated zone of the heath4.jpg (by; Alan HEATH [Nottingham,UK]) as being 500 km in diameter, and now that I've applied some further math in order to best identify what a reasonably focused beam of xenon/mercury photons striking the bottom of them clouds might have, this is in fact diffused out to that zone of perhaps at most 500 km, that is unless the originating source were of an even larger diameter and/or of greater divergence to start off with.

Surely a smaller and more focused beam would only improve upon reducing the exit illumination zone, whereas cloud and haze depth are of the primary divergence factors, then of cloud elevation and/or source distance from the cloud base being second. The nighttime clouds should be at least 10% lower than by day, and perhaps 20% thinner, as such the nighttime season of cloud illuminations should be offering a somewhat smaller diameter, perhaps as little as 50% the daytime illumination if generated by the same source, although the nighttime illumination energy should require but 10% of creating a daytime event.

The maximum parabolic diameter that I might otherwise suggest upon is 1000 meters, although that only adds another 0.5 km factor into the overall end result, which is merely a 0.1% shift. Thereby a larger diameter of source might only be necessary for improving the focus, of which due to the tremendous amount of divergence and/or diffusion created by transmitting through them clouds makes the need as for anything in excess of a km worth of parabolic source somewhat unnecessary, though perhaps offering a bit more photon delivery efficiency, which certainly could be a factor if there were a shortage of energy by which to drive such an illumination. Although, upon Venus there's hardly anything but a shortage of energy.

Because the bulk of the atmospheric suspended acid is in fact in a transparent droplet form (more spherical droplets than not, and of at least 25% H2O if not 33% H2O) rather than crystal, as such the opacity of such a cloud barrier would not likely fall below 10%, in fact it would be just as likely that a window of 25% opacity for the 400~450 nm spectrum would exist, thus as much as 25% worth of those original photons will manage to illuminate through the clouds to a point where others as snookered and arrogant as far too many Earth humans might notice.

Ongoing observations of such illuminations within the Venus seasons of daytime, as well as for those noticed of their Venus season of nighttime is in fact offering the utmost unusual of all observed topics among all other observed planets, at least as far as this facet being most likely artificial than not. That combined along with the rather obvious notations I've made on behalf of other life for more than three years, of there being significant numbers of massive structures, including a few complex reservoirs, a modified surface feature looking very much as a sizable tarmac, but then there's also a rather substantial rigid airship parked partially into it's hanger or storage bay, with a couple of rows of spherical storage tanks recessed into the landscape (gees folks, I wounder how the hell mother nature managed to accomplish all of that?) along with creating a rational township like community, having of all things a somewhat central parabolic item of good diameter, and of that parabolic item having a central spire or tower is sort of another dead giveaway. Perhaps the fact that there's clearly a nearby suspension bridge that's spanning a rather substantial canyon/rille, along with all sorts of other highly unusual and thereby interesting items of a more likely artificial nature than not, all of this is apparently asking of our crack NASA moderated observers that have been opposing essentially everything under the sun, and to be telling us we need to ignore absolutely all there is, including ignoring and/or skewing the laws of physics, and not to even mention our having to avoid laws of common sense.

Good grief folks; if there's another planet under our observation that offers even 1% as much to work with, perhaps we should be doing something about it. As not even from all that we've obtained from Mars is worth 1% of what's been discovered about Venus, and that a fact.

If you can provide other numbers for those "ashen lights" as illumination spots, such as their worth of lumens, watts/m2 or photons/m2, and of the peak spectrum involved, and/or anything further upon the topic of "earthshine", or of what any good sort of xenon/mercury illumination cannon or laser might otherwise deliver towards Venus, I'd certainly be interested in including that sort of data, or at least including a link into your research.

There's also a perfectly good side topic of interplanetary quantum packets, a worth of photons being frequency modulated as well as amplitude modulation that'll be sure to knock your shocks off.

Hi Albert,
I saw that one alright, but all that proves is that the dark side of Venus is hot ??? which all of Venus is all of the time...

A poker from a fire is hot, but it doesnt necessarily mean it always glows in visible light.

Obviously nighttime remains as too freaking humanly hot, but exactly how hot is hot?

At 5 km I've got the elevated nighttime surface temperature pegged at roughly 625°K, and perhaps at absolute minimum 550°K.

There has been a good number if IR images of Venus, though is there a specific reference data set as to those IR imaged colors?

I understand that the daytime cloud density varies by a ratio of 20:1, thus what is the nighttime density variance?

If it's somewhat cooler on the nighttime side (2900 hours worth), as would the physics formula of "energy in = energy out" statement imply, then of potentially how much less altitude and/or of greater cloud density ratio is there to work with?

Obviously those nighttime clouds must radiate whatever their daytime exposure absorbed, plus conducting away a little something other as extracted from the planet itself.