/sci/ - Science & Math

And that's just one of 7, right?

Talk about an enormous instrument.

>>5393348

18

>>5393343
>tfw NASA will be able to see what I'm masturbating to.

From Space.

>tfw you will never play a role in humanity's greatest feats

>>5393385
>>5393380
>>5393343

>>5393387
>>5393380
>>5393343
>>5393385

>>5393343
>>5393380
>>5393385
>>5393387
>>5393389

>>5393390
>>5393389
>>5393387
>>5393385
Quick question, why is this hexagonal instead of round?

>>5393343
>>5393385
>>5393387
>>5393389
>>5393390

>>5393392

Because they can't make a round mirror that size. Hexagons fit together nicely.

>>5393392
So it can be made with separate parts. There's a numberphile video on how Hexagons are the polygon with most sides that can be stacked like that.

>>5393380

those mirrors are beautiful

are we going to be able to see all kinds of cool shit with this mirror or what? how much better than hubble?

>>5393393

>>5393393
can't imagine the missing surface area on the edges doesn't affect the picture quality

>>5393398

I don't know exactly what we'll see but I do know:

>>5393393

The mirrors are MUCH bigger than Hubble.

It is optimised for infrared.

I think we'll see colder/lower energy stuff far away...

>>5393408

i cant wait

we are bound to see a ton of amazing stuff

>>5393398

Spitzer and Hubble made this.

How much more zoom will we get?

>>5393415
Let me say this, alien tits.

>>5393417
>alien tits.
Can telescopes zoom in on actual planets? As in, to check for life and stuff?

>>5393420
Nope!

>>5393420

planets dont emit enough light to be able to properly view them

we can know that there are planetary systems though through a variety of methods,

tl;dr we know the planets are there we just cant see them

>>5393428

I should probably qualify that and say that planets never really emit light they just reflect it

the reflected light is not enough to be able to see them

>>5393415
oh god, shit will be sooooooo cash

>>5393428

What's the best we can zoom in on a single star?

Can JWST focus on a single star?

>>5393399
>>5393385
>>5393380

>>5393437

I wish I knew more about physics and optics to answer that

itd be cool to see the specifications on this or at least some math saying how far away we will be able to see with this telescope

maybe they arent releasing that information yet

>>5393438

just look how fucking shiny that shit is

are they smudge resistant or do they just keep it mega clean

>>5393438

>>5393440
the latter

>>5393439
There is a very basic law out there regarding the proportional size of the aperture and the maximum object you can view over time, how small and far objects you can see is a function of both aperture and the amount of time it focuses on an area. This to my knowledge is how hubble got some of its amazing shots by taking in photons over many days. However there is a limit to how sharp and clear such an image can be unless both objects are remaining relatively still to one eachother, which they are not. Needless to say to get a really clear picture of a far away planet would require a lens many magnitude larger than this, in the range of of miles large. We can already use composite imagery to make very crude images of the closest brightest stars.

>>5393440 smudge resistant

Super mega clean

I think if you touch it, it will need sent back to be expensively rebuffed by a machine.

>>5393443

>However there is a limit to how sharp and clear such an image can be unless both objects are remaining relatively still to one eachother, which they are not.

I was thinking about this, its like when you set a long exposure time on a picture you have to keep the camera really really still or you get a blurry photo

>>5393443

JWST is destined for the L2 Lagrange point. Will this allow longer exposure times?

>Released on September 25, 2012, the XDF image compiled 10 years of previous images and shows galaxies from 13.2 billion years ago. The exposure time was two million seconds, or approximately 23 days.

>>5393450

>>5393454
Pretty

>>5393454
Is this the one that covers an area of the sky about 2 square centimetres? Blows my mind

>>5393462

>Blows my mind

mine too

space is so expansive the human mind isnt really capable of comprehending how expansive it really is

>>5393462
yes, it's the latest deep field picture they released. With the JWST we will be able to go even deeper (hue).

>>5393450
doubt it, but it will mean less gravitational fluctuation on the mirrors, and less uneven heat distribution from passing in and out of shadows

>>5393483

Just looking at it, because it's not orbiting a planet, it appears to make sense if it's getting disturbed less

>>5393454
In that image some galaxies appear the same size. Can some be really close and small while others are really far away but really huge?

That's an awesome picture, it's much better than the older deep field.

>>5393472
>(hue)

Did you say this like huehue retard style or do you mean it literally has something to do with the hue?

why aren't outermost pieces rounded?

>>5393415
The important part is that JWST is more comparable to Spitzer than it is to Hubble. JWST will have 10 times better resolution than Spitzer but about half that of Hubble. Angular resolution is not the only metric of a telescope.

>>5393437
JWST will have lower resolution than HST (Hubble). It will be able to resolve a few of the largest and closest giant stars like Betelgeuse and Mira but it will not be able to resolve Sun like stars.

>>539344
> how small and far objects you can see is a function of both aperture and the amount of time it focuses on an area.
This is not true. Time will not improve the size that you can resolve. The relation you are referring to is the Rayleigh criterion. Hubble got good resolution because it was above the atmosphere which blurs images. Nowadays ground based telescopes can over comb this but they could not 20 years ago.

Can anyone explain how the light refracts from the hexagonal mirrors and magnify ? I can't comprehend the mechanics behind it.

>>5393904
Why would they be? sounds like lost surface area to me.

>>5393462
Square centimeters are not a unit of angle, that's not a size on the sky.

I remember being excited until the launch date got pushed because the government held back funding. No, you can't have an extra billion now. But we'll delay the shit out of this and make you wait for the planets to align, before giving you an extra $4 billion instead. And then we'll blame NASA.

>>5393450
Theoretically yes but in reality you don't expose for too long in case a problem develops with one frame like a cosmic ray or a read out error.

>>5393929
It works though if you hold the ruler the right distance from your face...

>>5393483
>gravitational fluctuation
Hubble is in orbit, it wouldn't notice changes in gravity. Tidal forces would never affect something so small.

>less uneven heat distribution from passing in and out of shadows
Hubble has thermal insulation and Sun protection. The optics does not heat up with the Sun.

>>5393924
How do the next gen ground based megatelescopes compare in resolution? The lot aimed for 2020+ completion.

>>5393932
It is NASA's fault here. Cost estimates doubled before the first launch date was put back. Now it has been delayed 4-5 years and is around four times it's original estimate. The management was the original problem. Delays have driven the cost up but it's not the governments fault that NASA's margins were not large enough. The government never withheld money JWST had planned for but it did deny increases that were asked for in order to keep on schedule.

>>5393934
Yes but you do need to specify a radius.

>>5393953
I see. I guess I'm upset but I don't know who to be upset with.

I wonder if a large project like this could ever be done by an external organization, like a crazy astronomical charity. And then make all the design and models open-source, so any interested scientist could put in his/her 2 cents on a weekend.

>>5393946
The 3 upcomming extremely large telescopes (and mirror diameters) are the European Extremely Large Telescope (39.3m), the Thirty Meter Telescope (30m) and the Giant Magellan Telescope (25m, aperture not filled). In rough terms the gain in resolution is one telescopes diameter divided by the other so GMT has a factor 10 better than HST (2.54m).

In reality it's harder than that because ground based telescopes need very sophisticated instruments that can cancel out the movement of the atmosphere, so it won't be able to reach these resolutions before it gets an adaptive optics instrument.
The second point is that the comparison of resolutions assumes the same wavelength of light is being used. I think HST is only diffraction limited at about 500nm but I can't find a citation for that, below that wavelength resolution should improve but because of the way the camera is set up it cannot improve (e.g. because of the pixel size). When the ELTs set out they will likely not have adaptive optics in the visible region so they won't beat Hubble so badly, at least not for a while.

>>5393974
The trouble is that you need absolute design clarity and everyone needs to be highly skilled engineers. Astronomers get to out in their 2 cents when the science capabilities are being defined and when the instrument is undergoing design review. They can tell you how an engineering decision will affect science but they cannot tell you what's best from an engineering point of view.

There is an organisation who are building a mission to chart the near earth asteroids.
http://b612foundation.org/

Not so much in space but defiantly on the ground there are independent organisations that built telescopes, most are registered as charities.
The best supported is the European Southern Observatory who operate the VLT and soon the E-ELT as well as other telescopes. The Carnegie foundation is funding much of the GMT.

>>5393993
Yes, somehow I failed to mention engineers (the category I fall into), who arguably do most of the work in making projects a reality. I bet you could create some kind of software framework with a web interface that would keep track of a user's credibility, etc. You would need some hierarchy, and you'd obviously need some central location where the highest members can be actually on-site, but with the right processes in place, enforced by software (and not people), I think it could work.

b612foundation looks cool, thanks!

bump because this is one of the only actual science threads on /sci/

How is this thing going to hold up against micrometeorites? There's no shield around the mirror like Hubble, so the mirror's exposed to whatever space can throw at it. Do you just not get them that far out from a planet?

>>5394217

the mirrors are beryllium so it seems like they are pretty tough also the odds of being hit by a micrometeorite is pretty small because the telescope itself is relatively small

>>5394224
Actually it's because beryllium is relatively soft that it will do well. An impact will make a small hole in the reflective surface, if it was harder it could chip. It will be hit by many micrometeorites over many years but the overall effect on performance will be small, very small. There was a discussion about it in the main JWST paper, I'll see if I can find it.

>>5394243
From the paper
>The damage estimate from these studies was on the order of 7.3 × 10−4% over a 10-year mission. These studies combined with the L2 environmental conditions show that the degradation of the optical throughput for JWST will be negligible.
From Lightsey 2012

I wear the exact same outfit as that guy, including those boots with the red straps. Granted, there aren't so many clothing options in cleanrooms but it's still kind of cool to see.

>>5394278

where do you work?

is it fun?

First Boards of Canada, now NASA? I think the hexagon is now going to be the most important shape in our existence. It will be this new era's wheel.

>>5394356
Bees. My god.

>>5393862
the former

>>5394356

Hexagonal tiling is the densest way that polygon's can be packed in 2 dimensions. Even spherical packing is most efficient in hexagonal close packing.

NASA is simply trying to be perfectly efficient.

>>5393348
> Talk about an enormous instrument.

>>5394350
I do research at a university. At times it can be fun, but at the same time it is also very frustrating especially when you're troubleshooting a new process.

>>5393927
>>5394394
>>5393395

The mirrors are not arranged flat on a 2D plane, they have to tilt to make a curve.

7 actuators per segment, each having silly small accuracy requirements.

http://www.esmats.eu/amspapers/pastpapers/pdfs/2006/warden.pdf

>>5394356
Every time a company wants to convey something "scientific" or technologically advanced, they use hexagons. They're everywhere in our media, but most people don't notice them.

See below, for example: The computer company that sold me my laptop just recently.

http://www.eurocom.com/

>>5393993
>>5394059

Nothing NASA does is straight forward. Their facilities and equipment need specially built to suit the mission and the sheer volume of research, testing and development they do is mind boggling.

Maybe there are some small things that could be crowd sourced online but overall no, I don't think large projects could be done like that.

>>5394498
Other notable hexagons include

- Graphene

- Saturn

...

I thought I could think of more

>>5393431
Pretty sure earth emits a tiny bit of light, all man made but still..

>>5394586

Shouldn't Earth be constantly emitting some level of infrared just because it's warm and not dead?

>>5393924 >JWST will have lower resolution than HST (Hubble). It will be able to resolve a few of the largest and closest giant stars like Betelgeuse and Mira but it will not be able to resolve Sun like stars.

Googled "resolve betelgeuse" and got this picture.

Can JWST improve on this?

Will we ever be able to view and monitor solar activity in a similar way we do to our sun?

I don't know optics very well but does a larger mirror automatically mean you get a more zoomed image?

What is to be expected from these giant radio arrays people have been talking about? I recall reading about how there's a plan to practically use the entire planet as a giant telescope, lots of reflectors on the ground beaming to a satellite that acts as a sub-reflector.

>>5393428
>Bitches don't know about my direct imaging of HR8779

Gold eh?
What if it were to be stolen by the world's greatest thief....from space!?

The JWST's biggest feature is not the size of it's mirrors, but the colour. In the images that the Hubble took of the farthest away galaxies ever observed, they were so red shifted because they were moving away from us at such a rapid rate that they were almost invisible. The gold plating on the JWST's main mirrors will allow it to view infra red objects, objects MUCH more red shifted than the farthest of Hubble objects, and hence more distant objects, it will basically be able to see the universe's first galaxies forming. However, we are unlikely to see the stunning pictures synonymous with the Hubble as the telescope will not function as well in the visible spectrum.

>>5396241
>implying it has to be visible to represent it visually.. full retard

>>5396214
What am I looking at?

>>5396265
I feel you misunderstood my sentiments, I simply meant that the objects we would normally be able to see will not be as beautiful. ie, we're gonna have great pictures of the dust lanes in galaxies, but not necessarily the shiny stars and such. :)

>>5396278
>I feel you misunderstand physics.

Image related from Herschel at 370 μm....
magnitudes of scale beyond the wavelength of JWST,
there will be more than enough to gaze at

>>5396300
>post image that agrees with my post
-"ie, we're gonna have great pictures of the dust lanes in galaxies, but not necessarily the shiny stars and such"

>imply im retarded

>>5393343
Isn't it 2018 ?

>>5394538
you forgot... BEES

It would suck if the shuttle explodes on take off.

Forgive me as a simpleton....If its gonna be all kinds of far away...What if it fucks up and requires maintenance? Is it just fucked?

>>5396457
yeap. even in low earth orbit, we no longer have any means of repair now that the space shuttle is offline, so it's just as fucked as it would be otherwise.

>>5396459
>>5396459
Lol as an american tax payer that is properly disconcerting.

>>5396466
i did however just outline the ONLY benefit of the space shuttle, so don't be do depressed, in every other regard it is worse than conventional rockets.

>>5396474
Your forgot the benefit of it being awesome.

>>5396435
2017 at the very earliest. I was being optimistic :(

>>5396278
JWST will have no problem seeing stars.

>>5396241
It's a myth that JWST's pictures will be less attractive.

>>5396190
>Can JWST improve on this?
No, that image was take by an 8m telescope at the VLT, JWST is no bigger. The resolution in the picture is a bit better than ten times what can be expected with JWST.

>Will we ever be able to view and monitor solar activity in a similar way we do to our sun?
Not in the foreseeable future no. Some interferometers can resolve the disks of Sun like stars but that's nothing like what we have for the Sun.

>I don't know optics very well but does a larger mirror automatically mean you get a more zoomed image?
It opens the possibility for higher angular resolution but it doesn't dictate it.

>What is to be expected from these giant radio arrays people have been talking about?
We already do VLBI work over the diameter of the earth, the Square Kilometer Array would bring tremendous sensitivity but not really more resolution.

>lots of reflectors on the ground beaming to a satellite that acts as a sub-reflector.
That's not how they work. They don't use satellites at all. Radio telescopes have recovers, they will transmit the data along fiber optic cables to what will be the worlds largest super computer. The volume of data generated will be too high for a satellite.

>>5396516
http://www.newscientist.com/article/dn20705-space-telescope-to-create-radio-eye-larger-than-earth.html

I think this is the original article I read.

Thanks for the answers.

>>5396541
That doesn't use reflections from reflectors on the earth. Spektr-R is just a normal small radio telescope, the only reason it's in space is so it can get more distance between individual telescopes whilst doing interferometry. It is not part of the SKA.