Too tired to type but here are some good reading on the subject...
You're seeing bloom - it's an artifact caused by imperfect cameras and bright light sources. You can read more
here.
Possibly ironically, the author of that article states, "Don’t put the sun in the shot," but I suppose the guys over at ULA didn't read that article.
Pipinpadiloxacopolis[
S] 1 point 1 year ago*
It seems a very special kind of bloom that conserves details so well though. It seems to capture the exact edge of the sun, instead of radiating from the edges of Venus... I expect bloom to look more like
this (i.e. radiating inwards from the bright bits, and fading fast with distance from the edge).
I agree that it does appear to be translucent.
Is Venus a gas planet? No. It's too heavy and we've landed on its rocky surface.
Is Venus hollow? No. Again, too heavy, and it would be ringing like a bell. Also, quite unlikely.
Are the materials Venus is made of, transparent to ultraviolet light? No. We know that none of the materials that we know Venus is made of, are transparent to UV light to the extent that the sun shines
right through the planet with low-energy photons.
Could it be due to lensing of some sort, perhaps caused by Venus's dense atmosphere? Unlikely. The refractive indices of the gasses comprising the atmosphere are known and the effect is not expected to occur with the configuration found on Venus. There might be an as-yet unidentified aerosol agent present which may give the planet a pearl-like lustre, but other similar effects would also be seen if this were the case.
Could it be an artefact caused by the image capturing equipment, technique, or the processing? Most likely. It may be that some instrument does not capture a single moment, but rather records the
change within a short moment, or the difference between two moments, in which case there would be superimposition of images in the record. Or, perhaps the instrument combines data from more than one source to produce its final image, which too would lead to apparent transparencies.
Not enough is known about the exact details of the equipment and processes involved in creating the imagery to exclude this as a cause, and with most other causes ruled out, it may be said with great confidence that the explanation for this phenomenon lies in the part we don't know enough about.
GG_Henry 3 points 1 year ago
It's almost certainly an artifact due to the camera or compression or transmission or upload our stream.
Pipinpadiloxacopolis[
S] 2 points 1 year ago
That's a very Vulcan answer!
And I mean that in the best way. You're right, it's probably very specific to the way these particular images were created, if no-one recognises a known cause.
image: http://public.media.smithsonianmag.com/legacy_blog/20040608_Venus_Transit.jpg
[/caption] Every century or so, something truly special happens in the sky, and it happens twice: Venus passes in between the sun and earth. The transit of Venus, as it's called, comes in pairs spaced exactly 8 years apart, with each pair separated by gaps more than 100 years long. As a result, only 8 transits have occurred since the invention of the telescope. The most recent one was in 2004, and the second half of the pair is next week, during sunset on June 5th for North American observers, and during sunrise on June 6th for many in Europe and Asia. After this, the next one isn't until 2117. Why does it happen so rarely? Two events need to occur at the exact same time for us to see a transit of Venus. First, Venus needs to pass between us and the sun, so that to an observer looking down at the solar system, all three bodies would be in a straight line. This happens every 584 days, as shown in the bottom part of the diagram below. [caption id="attachment_10068" align="alignright" width="300" caption="Transits of Venus are so rare because the planet must pass between earth and the sun while lining up vertically, as well"]
image: http://public.media.smithsonianmag.com/legacy_blog/Transit_diagram_angles-300x200.png
[/caption] However, Venus also needs to line up vertically so that it appears somewhere in front of the face of the sun from our vantage point. Because Venus and the earth don't orbit the sun on the exact same plane—Venus' orbit is tipped 3.4 degrees relative to ours—most of the time it's too high or too low, as shown in the top part of the diagram. It only lines up in all 3 dimensions and traverses across the sun four times during an unusual 243 year cycle, with the transits coming in pairs separated by alternating periods of 121.5 and 105.5 years. In the United States, the transit will begin at roughly 6:04 Eastern, 5:04 Central, 4:05 Mountain, and 3:06 Pacific Time. Over the course of several hours, Venus will appear as a small dot moving slowly against backdrop of the sun. As with a solar eclipse (or anytime, really), looking directly at the sun can severely damage your retinas, so you should use a special filter or simply project the sun onto the ground or a piece of paper, by holding up a piece of cardboard with a small hole punched in it and allowing the sunlight to pass through. Historically, the transit of Venus played an important role in helping astronomers learn about the dimensions of our solar system, says
Owen Gingerich, professor of astronomy and history of science at the
Harvard-Smithsonian Center for Astrophysics. "The first observed transit was in 1639, but it was in 1716 that the astronomer Edmund Halley noticed that the geometry of it could be useful in determining the distance to the sun," he says. "At the time, the relative distances between the planets was well known, but not the absolute scale of the solar system, and without the absolute scale, you couldn't know how big the sun was." When the next pair of transits came, in 1761 and 1769, the scientific world was ready. "There was an international campaign set up to make the observations, and you needed observers from as far removed places on earth as you could get," says Gingerich. Scientists were dispatched to everywhere from Newfoundland to Tahiti to gather as much data as possible, and at each location, observers attempted to measure as accurately as possible just how long it took Venus to traverse the sun. As Halley had pointed out, if one knew the exact distance between two points on earth—Newfoundland and Tahiti, for example—and also calculated the difference in how long it took Venus to traverse the sun from each of these vantage points, the principle of
parallax could be used to determine the size of the sun itself, and with that our distance from it. "From each observatory, you would get a slightly different measurement for the length of Venus' path," Gingerich says. "And in fact, if you take three of the best observations from 1769 and use them in the calculations, you get a result within 1 percent of the modern value of the size of the sun." Although the transit is no longer as scientifically significant as it was in the 18th century, it will still provide valuable data for many observers. Our ongoing discoveries of planets in other solar systems, for example, depends on the intermittent dimming of distant stars as their planets pass in front of them. Calculating just how much Venus causes the sun to dim during the transit might help us more accurately understand these far-flung exoplanets. Whether you watch the transit to make complex calculations about exoplanets or just to see something unusual in the sky, we have just one recommendation: You'd better not miss it. The next few transits will be in December 2117, December 2125, June 2247 and June 2255. Your grandchildren and great-grandchildren might be watching, but you won't be around to see another one.
Read more:
http://www.smithsonianmag.com/scien...ont-of-the-sun-180947493/#YyD2C6tkbrQ0LZQE.99
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