Inside an Opening Telescope

[@OregonPepper]

Brady your enthusiasm is contagious.

[@DSB42]

amazing stuff Brady

[@DeepSkyVideos]

cheers for watching

[@Galakyllz]

Yes, another video from Brady (and a DeepSky video at that). I really enjoy when you talk to the astronomers too. (hint hint)

[@MrCanigou]

Awesome job as usual, Brady

[@andrewlabat9963]

Massively impressive. Thanks for such great videos..

[@JeroenBaxexm]

Truly amazing!! Thanks for the great video! And the detail

[@ojooto1988]

Stunning video Brady. Keep them coming. :-)

[@Zlopras]

amazing. the dust on the mirror really surprised me

[@jdgrahamo]

Perfect -- thanks Brady.

[@bracka_lv]

Thanks for sharing. Very interesting and your commentary was also meaningful. Brilliant!

[@stufromoz8164]

Awesome, thanks for posting and G'day from Australia...

[@amrahill]

Fantastic video!

[@ishmiel21]

Awesome video!!!

[@AlanKey86]

2:18 - 2:35 ah, the very essence of Relativity!

[@kennethflorek8532]

Not relativity with a capital R.

[@philipsalter934]

this is grea! But found it quite hard to judge what perspective you were filming during the part where the mirror turns, maybe move the camera around more in those situations!

[@Neueregel]

Great scope !!

[@Signal6000]

Amazing video

[@naybobdenod]

Great video. Could you plz make a short video as to how they keep the telescope rotating,compensating for the the earths rotation.I`m intrigued about its accuracy and the mechanics. Thanks Sincerely JF ( UK )

[@RealDealHolyfield2099]

I've always wanted to go to a telescope like this. Watching this video is the next best thing. I wish I could build a house with a telescope dome on top!

[@reinux]

this is so awesome.

[@MistressGlowWorm]

A Ritchey-Chrétien telescope (a specialized variant of the Cassegrain telescope). The laser creates the artificial star. Adaptive optics to obtain a cleaner, higher-resolution image. This is magnificent ❤❤

[@JBenedetti1978]

Wow! Awesome!

[@zenzylok]

Fascinating photon collection device. Some of the photons interacting with that mirror are billions of years old.

[@TheRuffusMD]

these video of the large telescopes is great , thank you , do you have any videos of lasers being shot into space?

[@antvnakhs]

great telescope great tour , I love science

[@PinkChucky15]

Amazing! Thanks, Brady :-)

[@slpk]

Hey Brady, I hope we get to see you and your dad on Vietnam soon!

[@marianmusic7221]

@DeepSkyVideos It seems that all the big telescopes have an alt-azimuth-like "mount". How do they compensate for the apparent rotation of the objects in the sky? Even Hubble and JWST are moving relative to the studied objects. Thanks for all the amazing videos!

[@keeny24]

I've never felt like such a nerd, being just as excited as he is to sit and watch vents opening XD

[@mikemcfall]

Before it gets dark they take pictures of the sky called flats that allow the dust sitting on the mirror to be corrected for.

[@abpccpba]

Go to Kit Peak in Southern Arizona; at least 25 large telescopes, even one to study the sun.

[@x-shadow-x]

DeepSkyVideos why do they even need vents/need to open them? doesnt the secondary mirror obstruct the view of the primary mirror? what does it looks like looking through that telescope. do you have pictures? thank you :)

[@MrRobinhalligan]

Super cool i want one to

[@fllavour]

very interesting! I'm building a reflecting telescope, but I can't find any good mirrors. Where can I get an almost parabolic mirror, or a concave mirror with very long focus?

[@CelticSaint]

I'm sure there are suppliers of such things. If all else fails you could try to make your own.

[@Beer_Dad1975]

Make your own, it's not very hard - I ground and figured a 12" F5.5 out of a piece of ships portal glass when I was 15 years old - so anyone can do it. I would recommend "how to make a telescope" by Jene Texereau, its a really old book well out of copyright, and you can download it as a PDF off the internet, just do a search. Also join your local astronomical society, they are bound to have some people who grind their own mirrors who will be able to help you find the equipment and consumables you need - the only difficult stuff to get hold of is the pitch, the carborundum and the aluminium oxide or rouge for polishing, and of course a suitable blank.

[@rocklobstersteve]

You could try Orion optics. They sell mirror sets.

[@fllavour]

rocklobstersteve Thanks.

[@WilliamLeeSims]

Is the tertiary mirror also made of beryllium?

[@SolarMoth]

How do you clean those mirrors? A lot of Windex?

[@davidsweeney111]

great vid :)

[@teles2937]

How are the mirrors cleaned?

[@astrojuanda]

How do they clean the mirrors? Can it be done?

[@Direkin]

The primary mirrors aren't made of aluminium, btw. They're made of Zerodur *coated* in aluminium.

[@edwardcosta2931]

I'm really surprised at just how silent everything is. I didn't expect that at all.

[@KsanaKsini]

Is it open for public?

[@gmirreh]

I'm interested in how they keep the mirrors clean. Surely they don't just Windex it and wipe it :). Maybe some maintenance videos.

[@MrMartinhedin]

But... There is dust on the primary mirror??? Is there any way of cleaning it? Doesn't that dust distort the final image?

[@666Tomato666]

not in significant enough matter as it is on the primary mirror If you put a finger right before a long telephoto lens (300mm for 56mm film) you'll notice the image only getting a bit darker, but you won't see even an outline of the finger.

[@MrMartinhedin]

Ah ok! Well I was just thinking that such an expensive mirror would have been kept clean :P

[@newem1nem]

HEY BRADY! I hope you see this. Can you please do an episode on rouge planets and interstellar stars? Thanks!

[@TheRealSkeletor]

Rouge planets? So, Mars?

[@newem1nem]

No...planets without a parent star -.-

[@TheRealSkeletor]

H34dHun734R Oh, you must mean rogue planets, then.

[@joshcryer]

Did you see construction on the E-ELT?

[@DeepSkyVideos]

here is our visit to the E-ELT site: Extremely Large Telescope - Deep Sky Videos

[@joshcryer]

Oh man how did I miss that one? Thanks!

[@Rawmon94]

are we going to see the laser in action?

[@JBSKK]

still waiting for actual deep sky pictures or video

[@ParaglidingManiac]

Why don't they leave the telescope in horizontal position once they're done with the astrophotography? Otherwise - the primary mirror is collecting dust on it's surface.

[@Vagolololo]

I feel kinda sad after watching this video. I live in Chile and I've never seen this enormous piece of engineering

[@MrMartinhedin]

I feel more sad, you can at least go someday! I am to far away!

[@stiimuli]

Its interesting that you don't get a real sense of just how huge that thing is until someone walks in front of it . Also, CLEAN THE DAMN MIRROR! XD

[@Unidentifying]

interesting [:

[@derKarl_stp]

breaking this main mirror... brings a lot of bad luck :D

[@DeepSkyVideos]

yes, seven years bad luck would not be enough in this case!

[@PelegTsadok]

DeepSkyVideos I guess 70 years in jail.

[@derKarl_stp]

Peleg Tsadok I guess ther could be somethings else but JAIL,,, cleaning the whole thing after you broke it... including all the fine corners and machines... while being watched from behind by angry and pissed of scientists :P

[@MajorMandyKitten]

I think you're already unlucky if you tried to break that mirror. Lol

[@qoaa]

I want a lens that big to screw onto my DSLR camera harhar

[@stiqula]

Why aren't the mirrors made of silver? I thought silver reflected best?

[@BrandonFrancey]

When dealing with such large scale structures for measuring immense distances, reflectivity is only a single property that must be considered. Stability for a mirror to hold its shape, temperature sensitivity, minimum movement between slight temperature changes and even the cost of the material. It would be interesting to know why they chose the material for each mirror and why they didn't use other materials.

[@piranha031091]

No, in the visible, aluminium reflects best, when it is properly coated.

[@kennethflorek8532]

I am fairly sure, but not positive, that silver reflects more light than aluminum, although aluminum is not much less. Silver is not used on first-surface mirrors (where light is reflected before passing through another material, such as glass) because it oxidizes to a black, not reflective, and not very transparent, compound so quickly. The surface of all metals oxidizes in a matter of minutes, but some, such as aluminum, are translucent and thin. The oxide of aluminum is the same clear material, minus the color, as the gemstones ruby and sapphire.

[@piranha031091]

When it is a monocrystal, aluminum oxide is indeed a clear and transparent material. But the oxide layer you get by exposing metallic aluminum to air is not! it is made of many nanometer-sized crystals which cause a lot of diffusion of the light. That is why aluminum first surface mirrors always have an aditionnal coating on top of aluminum, made of Titanium dioxide and Silicon dioxide. meade.com/catalog/uhtc/ And it seems you were right about silver's reflectivity.

[@cricketnotcroquet]

I've been told Aluminium has better sensitivity in the blue while Silver has better sensitivity in the red. Gemini has a silver coating for this purpose.

[@TVFILMBUFF]

Completely expecting some Batman Villian's henchmen to come out and start firing at Brady.

[@ajtronic]

Its like being inside a giant robot's eye haha

[@Twiztidguy]

I'm looking to buy a telescope, unfortunately I only have 200 dollars to spend on it. Does anyone have an suggestions? I want to be able to see the rings of Saturn and get a nice view of Andromeda. We are buying a house this year so my budget is a bit low... but eventually i'll get the money to buy my dream telescope. 200 dollars will have to do this year.

[@abpccpba]

Hi: Instead of buying a scope for now. Go on the net and look around to see the scopes the are online. I know of one down in Southern Arizona near Green Valley. I have forgotten the name of the (Mount Hopkins) mountain with lots of scopes on top. If you do buy; look around for some Astronomy Clubs in your area. Talk to experts; they were where you are now long ago. Good Luck. If you are ever end up in Tucson AZ. go to see Kit Peak out side of Tucson; simple tours are available.

[@Twiztidguy]

Thanks for the reply, I did see a club here in Indiana. I will definitely check out the online scope. My wife wants me to hold off again on buying one. Which is understandable since we have a newborn baby and we are looking to buy a house. Eventually I'll get it. :)

[@KajoFox]

4 years later, have you gotten a telescope and if so, which one? :)

[@justinhill6206]

dream build a VLT on the moon

[@cpawp]

pls, move your cam more slowly...

[@Key3812]

1:43 Groupies

[@Zerepzerreitug]

nerd drool :)

[@Firglet]

What the crap is alumin... oh... darn brits.

[@jeremylourie5270]

How are the mirrors cleaned?

[@W-H-O]

I was wondering the same thing, though given how dirty it is, maybe they aren't lol