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Posted: 1/27/2016 2:29:03 PM EDT
[#1]
Quote HistoryQuoted:
ETA: Evolution could do us in in a number of ways too. I'd dare say that has already begun |
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Posted: 1/27/2016 4:44:25 PM EDT
[#2]
Quote HistoryQuoted:
This is from NASA's Planetary Fact Sheet: PLUTO Mass (1024kg)0.0146 Diameter (km) 2370 Density (kg/m3) 2095 Gravity (m/s2) 0.7 Escape Velocity (km/s)1.3 Rotation Period (hours)-153.3 Length of Day (hours)153.3 Distance from Sun (106 km)5906.4 Perihelion (106 km)4436.8 Aphelion (106 km)7375.9 Orbital Period (days)90,560 Orbital Velocity (km/s)4.7 Orbital Inclination (degrees)17.2 Orbital Eccentricity0.244 Axial Tilt (degrees)122.5 Mean Temperature (C)-225 Surface Pressure (bars)0 Number of Moons5 Ring System?No Global Magnetic Field?Unknown What stands out to me is the mean temperature = -225 deg C (-337 deg F). At that temperature, most things we think of as gases (nitrogen, carbon dioxide, oxygen, methane) are liquids or solids. Also, it's spin axis is tilted 122.5 deg from north. How can it be tilted more than 90 deg from north, it's not as if there's a big "North" printed on the pole.  Quote HistoryQuoted:
This is from NASA's Planetary Fact Sheet: PLUTO Mass (1024kg)0.0146 Diameter (km) 2370 Density (kg/m3) 2095 Gravity (m/s2) 0.7 Escape Velocity (km/s)1.3 Rotation Period (hours)-153.3 Length of Day (hours)153.3 Distance from Sun (106 km)5906.4 Perihelion (106 km)4436.8 Aphelion (106 km)7375.9 Orbital Period (days)90,560 Orbital Velocity (km/s)4.7 Orbital Inclination (degrees)17.2 Orbital Eccentricity0.244 Axial Tilt (degrees)122.5 Mean Temperature (C)-225 Surface Pressure (bars)0 Number of Moons5 Ring System?No Global Magnetic Field?Unknown What stands out to me is the mean temperature = -225 deg C (-337 deg F). At that temperature, most things we think of as gases (nitrogen, carbon dioxide, oxygen, methane) are liquids or solids. Also, it's spin axis is tilted 122.5 deg from north. How can it be tilted more than 90 deg from north, it's not as if there's a big "North" printed on the pole. The International Astronomical Union (IAU) defines the geographic north pole of a planet or any of its satellites in the Solar System as the planetary pole that is in the same celestial hemisphere relative to the invariable plane of the Solar System as Earth's North pole.[1] This definition means that an object's direction of rotation may be negative (retrograde rotation) — in other words, it rotates clockwise when viewed from above its north pole, rather than the "normal" counterclockwise direction exhibited by Earth's north pole.
Those wacky astronomers. |
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Posted: 1/27/2016 5:19:04 PM EDT
[#3]
you might be interested in this, article which talks to the people who designed the new horizons sensors in a little town in the UK
http://www.eetimes.com/author.asp?doc_id=1327882 |
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Posted: 1/28/2016 2:16:23 PM EDT
[#4]
I don't know what to say about this. Big weird thing found: http://www.iflscience.com/space/giant-invisible-structures-could-be-hiding-milky-way
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Posted: 1/28/2016 4:40:27 PM EDT
[#5]
Only 158 days until Juno reaches Jupiter.
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Posted: 1/28/2016 8:54:39 PM EDT
[#6]
V774104, the solar system’s most distant photographed object:
  Right now we don't know much more than this: This body, designated V774104 for now, lies 103 a.u. away in the direction of west-central Pisces — that's 9.6 billion miles or 15.4 billion km. |
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Posted: 1/28/2016 9:28:53 PM EDT
[#7]
Quote HistoryQuoted: V774104, the solar system’s most distant photographed object: http://www.skyandtelescope.com/wp-content/uploads/V774104-discovery-images.gif http://www.skyandtelescope.com/wp-content/uploads/Location-of-V774104.jpg Right now we don't know much more than this: This body, designated V774104 for now, lies 103 a.u. away in the direction of west-central Pisces — that's 9.6 billion miles or 15.4 billion km. http://www.skyandtelescope.com/astronomy-news/v774104-most-distant-solar-system-object-11212015/ |
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Posted: 1/28/2016 9:29:38 PM EDT
[#8]
Quote HistoryQuoted:
V774104, the solar system’s most distant photographed object: http://www.skyandtelescope.com/wp-content/uploads/V774104-discovery-images.gif http://www.skyandtelescope.com/wp-content/uploads/Location-of-V774104.jpg Right now we don't know much more than this: This body, designated V774104 for now, lies 103 a.u. away in the direction of west-central Pisces — that's 9.6 billion miles or 15.4 billion km. http://www.skyandtelescope.com/astronomy-news/v774104-most-distant-solar-system-object-11212015/ and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. |
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Posted: 1/28/2016 9:40:51 PM EDT
[#9]
Quote HistoryQuoted: and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. There are a number of models for how the solar system formed and several have the large planets forming closer in than they are now and during the chaos potentially ejecting a planet from or nearly from the system. Finding this planet will lend credence to those models. |
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Posted: 1/28/2016 9:47:00 PM EDT
[#10]
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bunch of big ones. looks like all those direct imaged are larger than Jupiter. I wonder if they can't see one smaller than that. Quote HistoryQuoted:
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That's amazing. It looks like the potential for about seven planets. http://upload.wikimedia.org/wikipedia/commons/f/fb/HD_106906_b_image.jpg http://en.wikipedia.org/wiki/List_of_directly_imaged_exoplanets bunch of big ones. looks like all those direct imaged are larger than Jupiter. I wonder if they can't see one smaller than that. I bet we can when the Webb space observatory is deployed! Posted Via AR15.Com Mobile |
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Posted: 1/28/2016 9:48:13 PM EDT
[#11]
Quote HistoryQuoted:
define failed star... Does Jupiter count? Because if the predictions are right the planet will be much smaller than Jupiter. Closer to Neptune in size... about 9 times the size of Earth. Quote HistoryQuoted:
Quoted:
and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. Jupiter is sometimes debated and in fact we had a long discussion about in in planetary astronomy. I would point out that Jupiter has a positive heat signature. It puts off much more heat than it should so the core has some reaction going on (not full on fusion of course). Jupiter is a Hot MOFO |
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Posted: 1/28/2016 9:53:49 PM EDT
[#12]
Quote HistoryQuoted:
Someone mentioned dragons? http://imgsrc.hubblesite.org/hu/db/images/hs-2006-01-a-xlarge_web.jpg 
Holy shit, its rocky dennis! |
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Posted: 1/28/2016 9:55:55 PM EDT
[#13]
Quote HistoryQuoted: define failed star... Does Jupiter count? Because if the predictions are right the planet will be much smaller than Jupiter. Closer to Neptune in size... about 9 times the size of Earth. There are a number of models for how the solar system formed and several have the large planets forming closer in than they are now and during the chaos potentially ejecting a planet from or nearly from the system. Finding this planet will lend credence to those models. Quote HistoryQuoted: Quoted: and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. There are a number of models for how the solar system formed and several have the large planets forming closer in than they are now and during the chaos potentially ejecting a planet from or nearly from the system. Finding this planet will lend credence to those models. |
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Posted: 1/28/2016 9:57:55 PM EDT
[#14]
Quote HistoryQuoted:
Right now the odds are pointing towards the universe ending in heat death long after the sun dies out. Basically the the universe will expand faster than gravity can pull matter together. If humans don't colonize other planets (which is impossible for the foreseeable future) the sun will kill us if we or an impact don't do us in. ETA: Evolution could do us in in a number of ways too. Quote HistoryQuoted:
Quoted:
Since what we see is light years old history, how much warning do we get when our universe has some final ending? Light seems to lie to us, not telling us what's now - it tells us what was. Just thinking out loud, actually thought of this last week - but it took this long to get posted. ETA: Evolution could do us in in a number of ways too. Just think. Every second that goes by now will extend how long our future travelers will have to go, unless the destination is Andromeda. Posted Via AR15.Com Mobile |
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Posted: 1/28/2016 10:28:03 PM EDT
[#15]
Quote HistoryQuoted: Just think. Every second that goes by now will extend how long our future travelers will have to go, unless the destination is Andromeda. Posted Via AR15.Com Mobile Quote HistoryQuoted: Quoted: Quoted: Since what we see is light years old history, how much warning do we get when our universe has some final ending? Light seems to lie to us, not telling us what's now - it tells us what was. Just thinking out loud, actually thought of this last week - but it took this long to get posted. ETA: Evolution could do us in in a number of ways too. Just think. Every second that goes by now will extend how long our future travelers will have to go, unless the destination is Andromeda. Posted Via AR15.Com Mobile We're in a swirling mass of stars. Some going away... some toward... and some not appreciably changing either way. |
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Posted: 1/29/2016 7:26:02 AM EDT
[#16]
Quote HistoryQuoted:
Yah, Jupiter would need to be about 100x larger to have fusion so this is far from a failed star. If there was a "failed star" out there we would have picked it up from it's IR emissions by now. Quote HistoryQuoted:
Quoted:
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and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. There are a number of models for how the solar system formed and several have the large planets forming closer in than they are now and during the chaos potentially ejecting a planet from or nearly from the system. Finding this planet will lend credence to those models. Only if we looked for it. JW will be imaging in IR wavelengths and be more definitive. Yes Jupiter would need to be 100x larger to start fusion but both Jupiter and Saturn are comprised of the corrected elements they just don't have the mass to get the full process started. Both emit more energy than they absorb from the Sun. |
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Posted: 1/29/2016 7:19:23 PM EDT
[#17]
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Posted: 1/29/2016 8:46:35 PM EDT
[#18]
Quote HistoryQuoted: Only if we looked for it. JW will be imaging in IR wavelengths and be more definitive. Yes Jupiter would need to be 100x larger to start fusion but both Jupiter and Saturn are comprised of the corrected elements they just don't have the mass to get the full process started. Both emit more energy than they absorb from the Sun. Quote HistoryQuoted: Quoted: Quoted: Quoted: and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. There are a number of models for how the solar system formed and several have the large planets forming closer in than they are now and during the chaos potentially ejecting a planet from or nearly from the system. Finding this planet will lend credence to those models. Only if we looked for it. JW will be imaging in IR wavelengths and be more definitive. Yes Jupiter would need to be 100x larger to start fusion but both Jupiter and Saturn are comprised of the corrected elements they just don't have the mass to get the full process started. Both emit more energy than they absorb from the Sun. |
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Posted: 1/29/2016 8:59:24 PM EDT
[#19]
Quote HistoryQuoted:
Jupiter is sometimes debated and in fact we had a long discussion about in in planetary astronomy. I would point out that Jupiter has a positive heat signature. It puts off much more heat than it should so the core has some reaction going on (not full on fusion of course). Jupiter is a Hot MOFO Quote HistoryQuoted:
Quoted:
Quoted:
and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. Jupiter is sometimes debated and in fact we had a long discussion about in in planetary astronomy. I would point out that Jupiter has a positive heat signature. It puts off much more heat than it should so the core has some reaction going on (not full on fusion of course). Jupiter is a Hot MOFO Jupiter may get hot, but its no where near fusion, to sustain or even begin fusion it requires about 80x the mass of Jupiter. if there were a brown dwarf its mass would have a much more noticeable effect. |
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Posted: 1/29/2016 9:05:02 PM EDT
[#20]
Quote HistoryQuoted: We have. There was a survey done. There is nothing Saturn's size or larger left to be discovered in our solar system. Quote HistoryQuoted: Quoted: Quoted: Quoted: Quoted: and about that possible 9th planet. (I feel it is a failed companion star due to the fact that very often stars are actually binary systems) I can't wait for the data to prove or disprove it. There are a number of models for how the solar system formed and several have the large planets forming closer in than they are now and during the chaos potentially ejecting a planet from or nearly from the system. Finding this planet will lend credence to those models. Only if we looked for it. JW will be imaging in IR wavelengths and be more definitive. Yes Jupiter would need to be 100x larger to start fusion but both Jupiter and Saturn are comprised of the corrected elements they just don't have the mass to get the full process started. Both emit more energy than they absorb from the Sun. |
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Posted: 1/29/2016 9:58:56 PM EDT
[#21]
Quote HistoryWe have. There was a survey done. There is nothing Saturn's size or larger left to be discovered in our solar system.
Quote HistoryWe have. There was a survey done. There is nothing Saturn's size or larger left to be discovered in our solar system.
Yup, WISE would have found it from the IR signature. Good point, but something is going on so I look forward to it getting figured out. |
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Posted: 1/30/2016 4:48:13 PM EDT
[#22]
Here's an informative vid on how the apollo docking mechanism works. It doesn't hurt that I would watch this woman read the phone book:
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Posted: 1/30/2016 9:45:11 PM EDT
[#23]
 Andromeda Galaxy if it were bright enough to see in such lighting conditions. |
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Posted: 1/31/2016 2:05:02 PM EDT
[#24]
The moon and Earth from the deep space climate observatory:
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Posted: 1/31/2016 6:55:54 PM EDT
[#25]
found this last night.
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Posted: 2/1/2016 1:18:06 PM EDT
[#26]
Quote HistoryQuoted:
http://i.imgur.com/TqwPQh5.jpg Andromeda Galaxy if it were bright enough to see in such lighting conditions. Wow, I didn't realize Andromeda was so big in our sky. That's to scale? |
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Posted: 2/1/2016 1:24:00 PM EDT
[#27]
Quote HistoryQuoted:
Wow, I didn't realize Andromeda was so big in our sky. That's to scale? Quote HistoryQuoted:
Quoted:
http://i.imgur.com/TqwPQh5.jpg Andromeda Galaxy if it were bright enough to see in such lighting conditions. Wow, I didn't realize Andromeda was so big in our sky. That's to scale? I had the same skeptical reaction, so I googled and found this: http://www.slate.com/blogs/bad_astronomy/2014/01/01/moon_and_andromeda_relative_size_in_the_sky.html I didn't double-check the math, but it sounds right. |
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Posted: 2/1/2016 2:04:26 PM EDT
[#28]
Quote HistoryQuoted:
http://i.imgur.com/TqwPQh5.jpg Andromeda Galaxy if it were bright enough to see in such lighting conditions. The image makes Andromeda look so close. |
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Posted: 2/1/2016 2:09:48 PM EDT
[#29]
Quote HistoryQuoted: I had the same skeptical reaction, so I googled and found this: http://www.slate.com/blogs/bad_astronomy/2014/01/01/moon_and_andromeda_relative_size_in_the_sky.html I didn't double-check the math, but it sounds right. Quote HistoryQuoted: Quoted: Quoted: http://i.imgur.com/TqwPQh5.jpg Andromeda Galaxy if it were bright enough to see in such lighting conditions. Wow, I didn't realize Andromeda was so big in our sky. That's to scale? I had the same skeptical reaction, so I googled and found this: http://www.slate.com/blogs/bad_astronomy/2014/01/01/moon_and_andromeda_relative_size_in_the_sky.html I didn't double-check the math, but it sounds right. |
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Posted: 2/1/2016 2:17:30 PM EDT
[#30]
Quote HistoryQuoted: The image makes Andromeda look so close. Quote HistoryQuoted: Quoted: http://i.imgur.com/TqwPQh5.jpg Andromeda Galaxy if it were bright enough to see in such lighting conditions. The image makes Andromeda look so close.  |
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Posted: 2/1/2016 2:23:23 PM EDT
[#31]
Quote HistoryQuoted: thanks. I was looking for the source but was reasonably sure it was right based on the listed apparent angular size of the Moon and Andromeda on the sky. Quote HistoryQuoted: Quoted: Quoted: Quoted: http://i.imgur.com/TqwPQh5.jpg Andromeda Galaxy if it were bright enough to see in such lighting conditions. Wow, I didn't realize Andromeda was so big in our sky. That's to scale? I had the same skeptical reaction, so I googled and found this: http://www.slate.com/blogs/bad_astronomy/2014/01/01/moon_and_andromeda_relative_size_in_the_sky.html I didn't double-check the math, but it sounds right. |
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Posted: 2/1/2016 2:33:59 PM EDT
[#32]
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Posted: 2/1/2016 2:43:11 PM EDT
[#33]
Quote HistoryQuoted:
or any of the millions of stars within our galaxy which are heading toward us and not away from us. We're in a swirling mass of stars. Some going away... some toward... and some not appreciably changing either way. Quote HistoryQuoted:
Quoted:
Quoted:
Quoted:
Since what we see is light years old history, how much warning do we get when our universe has some final ending? Light seems to lie to us, not telling us what's now - it tells us what was. Just thinking out loud, actually thought of this last week - but it took this long to get posted. ETA: Evolution could do us in in a number of ways too. Just think. Every second that goes by now will extend how long our future travelers will have to go, unless the destination is Andromeda. Posted Via AR15.Com Mobile We're in a swirling mass of stars. Some going away... some toward... and some not appreciably changing either way. Could be I'm wrong, but my understanding is even billions of years from now when our sun expands and destroys Earth, there will be places in the solar system capable of sustaining life. Even if interstellar travel were impossible, humanity (or whatever the dominant species at the time might be called) could potentially outlive the Earth by billions of years. Cool thread. |
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Posted: 2/1/2016 4:23:16 PM EDT
[#34]
Quote HistoryQuoted: Could be I'm wrong, but my understanding is even billions of years from now when our sun expands and destroys Earth, there will be places in the solar system capable of sustaining life. Even if interstellar travel were impossible, humanity (or whatever the dominant species at the time might be called) could potentially outlive the Earth by billions of years. Cool thread. If you have water you can survive. You can make energy... you can use it as shielding... drink it... grow crops with it... Basically if we have fusion worked out at that point any where with a water supply is "habitable" |
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Posted: 2/1/2016 5:51:07 PM EDT
[#35]
Quote HistoryQuoted: There are several moons around Jupiter and Saturn and I think Neptune and Uranus as well that have abundant water... definitely in ice form and several may have liquid oceans under their ice. That's now. The Sun will swell up to about the size of Earth's orbit... either engulfing the Earth or actually pushing it to a higher orbit. But the Earth will not be habitable at that point as the "Goldilocks" zone for the sun (distance where liquid water can exist on a planets surface) will have changed. If you have water you can survive. You can make energy... you can use it as shielding... drink it... grow crops with it... Basically if we have fusion worked out at that point any where with a water supply is "habitable" Quote HistoryQuoted: Quoted: Could be I'm wrong, but my understanding is even billions of years from now when our sun expands and destroys Earth, there will be places in the solar system capable of sustaining life. Even if interstellar travel were impossible, humanity (or whatever the dominant species at the time might be called) could potentially outlive the Earth by billions of years. Cool thread. If you have water you can survive. You can make energy... you can use it as shielding... drink it... grow crops with it... Basically if we have fusion worked out at that point any where with a water supply is "habitable" We're going to need some pretty fancy technology if we want to live on any of these places.   |
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Posted: 2/1/2016 6:20:21 PM EDT
[#36]
First image in the above posts says "Neptune may possess large, hot, highly compressed liquid ocean..." I thought liquids could not be compressed.
ETA: Well color me wrong. I've lived this long believing liquids cannot be compressed. Google says you can. 
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Posted: 2/1/2016 6:32:15 PM EDT
[#37]
Quote HistoryQuoted: First image in the above posts says "Neptune may possess large, hot, highly compressed liquid ocean..." I thought liquids could not be compressed. ETA: Well color me wrong. I've lived this long believing liquids cannot be compressed. Google says you can. |
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Posted: 2/5/2016 2:38:36 PM EDT
[#38]
The highest resolution picture ever seen in astronomy:
What do you get when you combine 15 radio telescopes on Earth and one in space? You get an enormous “virtual telescope” that is 63,000 miles across. And when you point it at a distant black hole, you get the highest resolution image every seen in astronomy.
Although it looks just like a big green blob, it’s actually an enormously energetic jet of matter streaming out of a black hole. And this black hole is 900 million light years away. As reported at Popular Science, it required an array of 15 radio telescopes on Earth, and the Russian space telescope Spektr-R, to capture the image. This technique—called interferometry—is like creating a telescope that is 63,000 miles across. The detail it provides is like seeing a 50 cent coin on the Moon. For perspective, the object in the image is 186 billion miles long, at minimum, and would just barely fit in the Oort Cloud. http://www.universetoday.com/127148/the-highest-resolution-image-ever-seen-in-astronomy/ |
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Posted: 2/6/2016 12:17:30 PM EDT
[#39]
The hills are likely fragments of the rugged uplands that have broken away and are being carried by the nitrogen glaciers into Sputnik Planum. 'Chains' of the drifting hills are formed along the flow paths of the glaciers. When the hills enter the cellular terrain of central Sputnik Planum, they become subject to the convective motions of the nitrogen ice, and are pushed to the edges of the cells, where the hills cluster in groups reaching up to 12 miles (20 kilometers) across.  http://digg.com/2016/pluto-photo-floating-hills-nasa |
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Posted: 2/6/2016 2:10:16 PM EDT
[#40]
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Posted: 2/6/2016 10:17:03 PM EDT
[#41]
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Posted: 2/6/2016 10:27:03 PM EDT
[#42]
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Posted: 2/6/2016 10:52:50 PM EDT
[#43]
Quote HistoryQuoted:
Could be I'm wrong, but my understanding is even billions of years from now when our sun expands and destroys Earth, there will be places in the solar system capable of sustaining life. Even if interstellar travel were impossible, humanity (or whatever the dominant species at the time might be called) could potentially outlive the Earth by billions of years. Cool thread. Even better, we could move the Earth to a larger orbit and survive the subgiant, and maybe red giant phase. Phil Plait describes it in one of his books. When we send probes to deep space we use a gravity slingshot from various planets to add speed to the probe. The reverse of this is the planet loses the same amount of energy. The huge mass difference means it's essentially unnoticeable to the planet. This also works in reverse, we can slingshot the Earth by an asteroid. Using a 60 mile wide asteroid passing 6000 miles from Earth would increase our orbit radius by about 10 miles. Use an onboard rocket to modify the asteroid's orbit to swing past Jupiter or Saturn again to pickup more energy, rinse and repeat 5 million times. We'd want to increase our orbit gradually as the sun heats up anyway so this isn't all that crazy at the timescales needed. |
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Posted: 2/6/2016 11:53:53 PM EDT
[#44]
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Posted: 2/7/2016 1:56:02 AM EDT
[#45]
Because this thread can't have enough Phil Plait, here's his writeup on the newly completed James Webb mirrors.
Here's one of the 18 segments, photographed through a window. Shiny. Also notice the NASA engineering of requiring you to unlatch the door to the clean room to put the window blocker back up. 
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Posted: 2/7/2016 2:48:30 PM EDT
[#46]
A glint of sunlight reflecting off a lake of hydrocarbons on the north pole of titan:
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Posted: 2/7/2016 3:53:06 PM EDT
[#47]
Quote HistoryThats the awesomest gif I have ever seen. Eta: ....that doesnt involve tits. |
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Posted: 2/9/2016 2:46:12 PM EDT
[#48]
This thread is awesome again!
Thanks, TescoVee. |
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Posted: 2/9/2016 9:43:22 PM EDT
[#49]
One big problem with the James Webb Space Telescope that is being considered is what if something goes wrong? We all know that Hubble didn't exactly work out as promised and needed a STS mission to fix it. That won't work out for James Webb because: a) we don't have space shuttles anymore and b) James Webb will be way out past the moon. Solution: build in redundancy because it would be difficult to fix something if it breaks. Here is one aspect of that design:
The James Webb telescope has a Far-IR and a Near-IR detector that can take images at the same time using a beam splitter:  Conventional beam splitters send half of all the light they receive through them and the other half back like a mirror. The upside is that if one detector dies you still have the other for imaging. The downside is that having only half the light doubles the amount of time to take an image. NASA's solution: Use a Dichroic Mirror. What's a dichroic mirror you say? It's a mirror that is reflective to one band of light but transparent to another. What you end out with is a beam splitter that has redundancy but doesn't sacrifice any imaging time.   |
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Posted: 2/10/2016 11:45:08 AM EDT
[#50]
How does that design help if the lens is ground wrong?
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