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Harm Reduction Notes for the COVID-19 Pandemic

I tried

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- Sun, 27 Sep 2015 23:01:19 EST NCcXgNdu No.55692
File: 1443409279643.jpg -(116934B / 114.19KB, 2592x1728) Thumbnail displayed, click image for full size. I tried
✓ Overcast
✓ Too late to set up tracking
✓ Sensor needs cleaning
11 posts and 4 images omitted. Click View Thread to read.
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Viktor Ambartsumian - Thu, 01 Oct 2015 16:29:43 EST 9+WA5MM9 No.55725 Reply
1443731383998.jpg -(643705B / 628.62KB, 2000x1333) Thumbnail displayed, click image for full size.
DICKS EVERYWHERE
>>
Margaret Burbidge - Sun, 04 Oct 2015 06:22:01 EST UwTIku3P No.55737 Reply
1443954121436.jpg -(116215B / 113.49KB, 500x661) Thumbnail displayed, click image for full size.
>>55692
>Using ✓s instead of s
Ban this heretic
>>
George Gamow - Sun, 04 Oct 2015 12:53:54 EST NCcXgNdu No.55738 Reply
>>55717
Satellites would only appear to move in one direction. It was probably some high altitude aircraft or weather balloon.

In the year 2069

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- Thu, 01 Oct 2015 01:09:01 EST WHXsRUFD No.55722
File: 1443676141681.jpg -(77479B / 75.66KB, 800x425) Thumbnail displayed, click image for full size. In the year 2069
If humans are going to build a city on the moon this century it should definitely be done in 2069, if they do it in 2068 or 2070 instead it will go to waste.

It'll go down as a historical fact until the end of time that the City/Colony was founded in 2069. IMO Earth's Moon is the most romantic spot in our galaxy so it might as well be associated with 69ing.

Becoming a multiplanet species, breaking free from nations.

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- Mon, 31 Aug 2015 16:52:15 EST P+fSJ1RL No.55648
File: 1441054335956.gif -(2406963B / 2.30MB, 256x170) Thumbnail displayed, click image for full size. Becoming a multiplanet species, breaking free from nations.
I want to start a discussion of becoming a multiplanet species. Weather that be on Mars, or one of the many Earth sized exo planets. for those let's assume a way to use the Alcubeirre equations has been invented To me moving out of our home planet is an inevitability. What I'm not so sure on is our penchant for clinging to imagined borders.

What is it going to take to break free from that? I could see Mars ending up being its own nationality so to speak. From a governance stand point I can see the practicallity, each planet will mostly be responsible for running it self. The alternative or events leading to that style would be akin to the Roman empire becoming too big to manage.

So yeah, general ideas, hopes, anticipation for how things will be. Discuss becoming a multiplanet species and the evolution of governance that will soon follow.
14 posts and 1 images omitted. Click View Thread to read.
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!qCv3kE3pMI - Wed, 16 Sep 2015 00:27:37 EST M7NMNbPp No.55675 Reply
1442377657015.jpg -(389862B / 380.72KB, 1280x1024) Thumbnail displayed, click image for full size.
gas vapor fed plants and printed meals, who wants to go there when being there is "there"?

p.s. nanana
>>
Daniel Kirkwood - Thu, 17 Sep 2015 00:09:14 EST P+fSJ1RL No.55676 Reply
>>55675
It sounds like a dim prospect. But with enough off hours with allowances for extra activities and maybe even EVAs for no O2 worlds. Could be fun, might be covered by shitty mega corps, but those involved will have to know that they signed up to head a new place to live. They get to forge a new planetary culture, even one day claim sovereignty. The galaxy is a large place and likely hard to govern.
>>
Bernard-Ferdinand Lyot - Mon, 28 Sep 2015 00:42:00 EST AlxomEpB No.55698 Reply
>>55673
Might not be a corporation though. It could be ideological or some psudeo religious movement.

First telescope

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- Thu, 24 Sep 2015 21:34:55 EST 6SPuxxpR No.55682
File: 1443144895835.jpg -(728331B / 711.26KB, 1920x1080) Thumbnail displayed, click image for full size. First telescope
Hello, I'm looking for some advice for a first time telescope buyer. I was thinking about buying the Celestron 76mm Firstscope as its not to expensive and if I find that if astrology is not for me it's not really a big loss. Any advice or other telescopes would be great thanks.
>>
Allan Sandage - Sat, 26 Sep 2015 04:08:14 EST NCcXgNdu No.55686 Reply
Dobsonians are going to be the best bang per buck. The larger the aperture, the more light gathering capability it will have. Plan to spend several thousand dollars for astrophotography minus the SLR or CCD to take pictures with. The mount is almost more important than the scope here. A heavy GOTO mount (equatorial pref) with tracking capability is important for taking long exposures although you can take many shorter exposure images and stack them in Photoshop. Store bought refractors are generally garbage. If you really want to go that route Explore Scientific makes some nice refractors. Newtonians are a different story. My nephew's other pop bought him a store bought Celestron Astromaster, and although the mount could blow over like a leaf, the optics on the scope were pretty good. Dobsonians are Newtonians on a lazy Susan like bottom mount with two forks. You can get a large aperture here for comparatively very little cash. The only downside is that it doesn't really lock in place. Besides refractors and newtonians, there are catadioptric cassegrains. These are reflectors like the newtonian, but they are compact and expensive.

tldr: the AstroMaster 114EQ is $200 at opticsplanet.com
Eyepieces cost $50 dollars. Don't start off with a scope that costs the same as an eyepiece.


Star Gazers

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- Wed, 02 Sep 2015 04:30:58 EST NCcXgNdu No.55650
File: 1441182658167.jpg -(447181B / 436.70KB, 1600x1001) Thumbnail displayed, click image for full size. Star Gazers
Any other star gazers out there with telescopes? How far do you have to drive to get to a Bortle scale 2 environment? White being 9 Black being 1.

http://darksitefinder.com/maps/unitedstates-8color.html
>>
Charles Bolton - Thu, 03 Sep 2015 02:43:21 EST lHGvTKQL No.55651 Reply
>>55650
I just have to drive for about 25-30 minutes west on I-70 to get to a Level 1 area out in the middle of Nowhere, KS. There's even some small towns and farming communities nearby where you could get some gas and snacks.

One of the perks of Kansas I suppose.
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Jacob Kapteyn - Sun, 06 Sep 2015 06:20:10 EST NCcXgNdu No.55655 Reply
My astronomy club has a dark site, but I have to drive 2 hours to get to it. They have a bunch of concrete slabs where you can set up and they're wired for electricity if you need to power servos on your mount. Some people have their own mini domes set up and there's a small building with a 16" scope and dome. I wish I lived closer to the sticks so I didn't have to drive so far to get a good view of nebula. My dad is originally from Nowhere, KS. I drive through there to pay respect to ghosts occasionally. I wouldn't mind buying a bunch of land and retiring there when I get old.

orbiter 2010

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!lwriJ94kMg - Thu, 20 Aug 2015 05:01:27 EST yA35CPLh No.55604
File: 1440061287082.png -(741213B / 723.84KB, 870x636) Thumbnail displayed, click image for full size. orbiter 2010
Inb4 telling me to post this on /vg/. It's a simulator not a video game. It's serious bzns and no fun is allowed. Besides I've posted it there before and no one there is cool enough to go to be interested in it.

Any one here ever try this out? I got pretty into it a while back. I've used various Delta glider models to launch from cape Canaveral, dock at the iss and then land on the moon at the fictional moon base. I've even made the trip home, but I can't re enter the atmosphere with out computer assistance. I either explode or bounce off the atmosphere every time.

I cant get my head around planning interplanetary trips. The MFD is too obtuse of a tool for me to plan that sort of trip. I wish there was kerbal maneuver node mod that let me visualize the trajectory vissualy with a 3d image rather than a 2d circle on a plane and some numbers.

I haven't tried it in a while and my gaming pc is dead, my lap top wont handle it. I recomend every one check it out as it's free.
12 posts and 1 images omitted. Click View Thread to read.
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James Mother Fucking Randi !lwriJ94kMg - Sun, 23 Aug 2015 21:05:00 EST yA35CPLh No.55617 Reply
>>55615
3d cockpit. My phones auto correct has been taking some creative liberties lately.

Math problem

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- Fri, 26 Sep 2014 14:29:27 EST vUNowU0Q No.54441
File: 1411756167954.png -(17766B / 17.35KB, 640x558) Thumbnail displayed, click image for full size. Math problem
Anyone want to help me out with this problem? I'm new to astronomy/physics and I haven't the faintest.
8 posts omitted. Click View Thread to read.
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Paul Goldsmith - Fri, 24 Jul 2015 21:11:43 EST euFuFwSC No.55558 Reply
>>54441

> A mass is dropped directly on top of a half circle. As it rolls of the side...

Top lel
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Edwin Salpeter - Mon, 31 Aug 2015 01:06:20 EST OMGzRHpD No.55646 Reply
1440997580737.jpg -(163342B / 159.51KB, 483x572) Thumbnail displayed, click image for full size.
is mass M a sphere or a cylinder? that changes the moment of inertia and the angular momentum of mass M. you said no friction but it's rolling so I'm lead to believe we are operating under the rolling-without-slipping regime (translational speed 'v' = radius of the mass M 'r' x 'omega', the angular velocity).

set up a force diagram for the mass at location X. the weight force 'mg' points straight down, we'll split into components in a moment. The normal force 'N' of the hemisphere on mass M points radially outward (in this case north-east). We'll be solving for the condition where N --> 0 (i.e., it juuust loses contact with the hemisphere)

cont.
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Edwin Salpeter - Mon, 31 Aug 2015 01:26:04 EST OMGzRHpD No.55647 Reply
now the weight force 'mg' can be split into components. one component points radially inward from X with value mgcos(theta). the other component points in the direction of mass M's velocity vector, tangent to the hemisphere or south-east, with value mgsin(theta). the first component balances with the normal force N and provides the centripetal acceleration for mass M. the second component does the accelerating of mass M down the hemisphere.

As >>54457 said, now do the conservation of energy. The translational kinetic energy 1/2mv^2 plus the rotational kinetic energy 1/2Iomega^2 will equal mg(R-y) where y is the height of location X. if you want it dimensionless (R=1) then R-y = 1-sin(theta). make the v = r x omega substitution and solve for v.

the inward radial componenet mgcos(theta) provides the centripetal acceleration v^2/R. So mgcos(theta) = mv^2/R ... too distracted to finish the rest but solve for the max v that the inward radial component can still provide a = v^2/R, then you can solve for the value of cos(theta)

frikkin relativity

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- Sun, 02 Aug 2015 19:56:50 EST Du35j2Lj No.55576
File: 1438559810297.jpg -(295824B / 288.89KB, 1041x1041) Thumbnail displayed, click image for full size. frikkin relativity
This has certainly been asked here before but please help me understand this.
A space ship travels around earth near lightspeed. I understand that velocity makes
time aboard the ship seem slower to a spectator on earth. And when the ship stopped moving the crew would have aged less then this spectator. But here's what i dont get. Why does the spectators time also seem to move slower to the crew on the ship? Wouldnt earth look like someone pressed fast forward? But lets say earth time seems to move slower, what happens when the ship slows down, does light from everything that happened come towards it like a flash?
I know i sound dumb, but that's okay.
2 posts omitted. Click View Thread to read.
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Pierre-Simon Laplace - Mon, 03 Aug 2015 06:26:06 EST v2I6+0VG No.55579 Reply
That's not a dumb question at all. In special relativity, there is no preferred reference frame. If a rocket ship is travelling past the Earth, from the rockets perspective, the Earth is travelling past the rocket. So each will see the other's clocks as ticking slower to their own. This symmetry only holds for inertial reference frames though (no acceleration or deceleration). In your example, the space ship is constantly accelerating to move in a circle, and this destroys the symmetry. A more illustrative example is the one of the twin paradox. In the twin paradox, the ship leaves Earth and travels near the speed of light for a while and then turns around and returns to Earth. One twin is stays behind on Earth, and the other travels on the ship. The one who stayed behind on Earth has aged more than the voyager twin. It's a seeming paradox, because each twin witnesses the same thing: the other twin flies off at breakneck speed and returns at the same speed. The difference is that the space ship twin feels an acceleration. It's this acceleration that causes the jump in time - known as gravitational time dilation. This is an aspect of general relativity - beyond the scope of special relativity. So yeah, as soon as the ship starts accelerating or decelerating (as in your example), the events on Earth will play out in fast-forward from the ship's perspective.

https://en.wikipedia.org/wiki/Twin_paradox
https://en.wikipedia.org/wiki/Gravitational_time_dilation
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Grote Reuber - Mon, 03 Aug 2015 08:00:44 EST Du35j2Lj No.55580 Reply
>>55579

Thanks you! That clears my thoughts somewhat. It's still hard to grasp though.
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Fred Whipple - Tue, 25 Aug 2015 23:42:03 EST P+fSJ1RL No.55636 Reply
>>55580
Don't worry. Our brains didn't evolve with innate knowledge of spacetime. Our universe has been what we see for a long long time. Recent science and tools have shown us more cogs of the universe we may never have other wise been made aware of.

That people here can even explain these things is incredible in itself. SpaceTime is no simple algebra that's for sure.

Night v/s day

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- Mon, 24 Aug 2015 22:12:00 EST Fk84gn/u No.55620
File: 1440468720383.jpg -(149638B / 146.13KB, 778x740) Thumbnail displayed, click image for full size. Night v/s day
Hey, so just as here on earth we've got longer days in the summer and longer nights in winter, is there a possibility for a planet, any earth-sized planet, to have a 6 hour day and, I don't know, a 40 hour long night?
1 posts omitted. Click View Thread to read.
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James Mother Fucking Randi !lwriJ94kMg - Tue, 25 Aug 2015 05:31:05 EST yA35CPLh No.55625 Reply
This reminds me of Time cube for some reason.

Discuss...

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!oj3475yHBQ - Wed, 08 Jul 2015 20:14:54 EST NjsLJs2P No.55484
File: 1436400894839.jpg -(114479B / 111.80KB, 854x687) Thumbnail displayed, click image for full size. Discuss...
If time is equal to the distance that light travels, yet slows as one approaches the speed of light, does this not indicate that the speed of light is actually timeless?

If the speed of light is timeless, yet time is equal to the distance that light travels, does it not mean that the observer is responsible for the conception of distance in relation to light?

If time is equal to the distance that light travels, yet the speed of light is timeless, than space/time is actually light, as a measurement of time is actually a measurement of light.

If a measurement of time is actually a measurement of light, but the speed of light is timeless, does this not mean that to measure light is to create time?
20 posts and 2 images omitted. Click View Thread to read.
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Karl Jansky - Tue, 11 Aug 2015 09:12:09 EST YHjXylC8 No.55591 Reply
11.jpg -(80085B / 78.21KB, 666x69) Thumbnail displayed, click image for full size.
>>55589
>Theoretically, if one could obtain a unicorn that could wish you to the nearest star system...
Even your imaginary unicorn would have difficulty, the top equation is time dilation at constant acceleration.
c= the speed of light, v=velocity. If v<c, you end up with an imaginary number.
>>
Bernard Burke - Tue, 11 Aug 2015 22:36:58 EST 415JX8nG No.55592 Reply
>>55484
It's relative.
If you yourself are traveling the speed of light, the closer you get to c, the slower time gets for you only, the rest of the universe starts to fast forward.

I guess a photon itself would be a timeless object, it has to interact with something to change.. but nothing quantum mechanical exists singularly, it exists in the context of the nature around it.
I guess in photon time, the universe is only a tiny fraction of a second old, if that is even an accurate description.
But the rest of the universe still matters.

The way I think of quantum mechanical objects is that they aren't like a ball or anything concrete like that.
A beam of electromagnetic energy is like a river.
You can run up to it with a glass, take a scoop out, and proclaim you have an electron.
You are measuring the location of that electron, as it is in your hand, but it's not going anywhere. You could then spill that electron out of the glass, back into the river. Although you don't know where that electron is anymore, you could figure out what it's speed is and where it is likely going based on the contours of the river, or getting out of the metaphor, the physical nature of what is going on around it.

Photons are only timeless to themselves, the rest of the universe collapses any notion of them existing in a timeless place.
If light didn't exist in time, I imagine, if the universe was able to form in the first place, it would just look like a big clump of white noise
>>
Fritz Zwicky - Thu, 13 Aug 2015 19:25:39 EST BF8zYeiD No.55595 Reply
>>55592
It sounds like you have a pretty decent understanding of what you're talking about, and you're good at communicating those ideas understandably.

The Universe and Your Significance

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- Wed, 21 Jan 2015 17:42:34 EST 7UdqYDqD No.54926
File: 1421880154554.jpg -(416926B / 407.15KB, 2560x1440) Thumbnail displayed, click image for full size. The Universe and Your Significance
I've noticed this a lot when people take about outer space and the universe they always like to mention how "insignificant" it makes them feel.
"Yeah man space, wow, you know it really puts my life into perspective; how insignificant we are in the grander scheme of things."

This is my opinion but I think that's such a belittling thing to say its also unsettling how common it is a thing to say when talking about the universe.

Granted the universe is huge, and in comparison us tiny humans are very very tiny. Doesn't make us insignificant though, or our lives meaningless.
You are the most significant person in your life, because without you, your life wouldn't exist. Who cares if you don't become famous or invent something that changes the world, you are the universe experiencing itself through your life, defining it with every thought, action, emotion and experience you have.

Sure you are a tiny droplet in an ocean of water, however what is an ocean but a multitude of droplets?
43 posts and 5 images omitted. Click View Thread to read.
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Gerard Kuiper - Tue, 10 Feb 2015 17:00:43 EST KSSVR3HT No.55021 Reply
We can compare for significance if we want. Compared to a rock im significant, I think. But we dont know what is actually significant, because we dont know what the fuck is going on.
I certainly dont see any reason to believe that all of this is good or bad, significant or not, either way.
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Terror Incognito - Fri, 20 Feb 2015 15:22:25 EST 7DU4fAaH No.55056 Reply
1424463745712.jpg -(16755B / 16.36KB, 375x500) Thumbnail displayed, click image for full size.
>>54926

The fact that we're alive right now, able to experience and observe all that is in the universe makes us the most significant part of it, regardless of how small we appear to be on a specific scale of perception.

Time dilation and the Alcubierre drive

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- Thu, 30 Jul 2015 12:30:55 EST /fL15l2I No.55567
File: 1438273855753.jpg -(16840B / 16.45KB, 200x303) Thumbnail displayed, click image for full size. Time dilation and the Alcubierre drive
if one were traveling above c in a ship using an Alcubierre drive, would they experience time dilation?
as i understand it, the object affected by the drive isn't moving but rather space is simply expanding and contracting around it. the object has no velocity and isn't moving in the normal sense.
>>
Karl Swarzchild - Thu, 30 Jul 2015 13:05:05 EST lHGvTKQL No.55568 Reply
>>55567
No, because the entire ship is contained within it's own stationary spacetime bubble.

The negative time generated by dilation will only speed up the journey relatively to the speed of light.

Stephen Hawking - Aliens

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- Wed, 22 Jul 2015 09:52:58 EST eZ452btZ No.55537
File: 1437573178193.gif -(145178B / 141.78KB, 250x250) Thumbnail displayed, click image for full size. Stephen Hawking - Aliens
Discuss

http://m.space.com/29999-stephen-hawking-intelligent-alien-life-danger.html

http://news.bbc.co.uk/2/hi/8642558.stm
7 posts and 4 images omitted. Click View Thread to read.
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Alan Guth - Wed, 22 Jul 2015 16:29:07 EST YHjXylC8 No.55545 Reply
1437596947747.png -(60177B / 58.77KB, 740x391) Thumbnail displayed, click image for full size.
>>55543
>the stars we observe every night are already dead.
Unless you're using a telescope to look at galaxies very far away, they're all within a hundred thousand light years and probably aren't dead.

>>55544
Pic related is a much better explanation for UFOs.
>>
Johann Bode - Wed, 22 Jul 2015 17:08:26 EST 415JX8nG No.55547 Reply
>>55545
Hahaha that's awesome.
It would be an interesting statistic to see how the numbers change from populations with lots of alien cultural references to others were it's less prevalent, and how it changes with the scientific education levels of the respective populations effect the out come as well.

I've seen one ufo, it was probably a meteor, about twice the size of the full moon, comparable color and brightness, but it didn't have a tail and it flew right over me. I've seen large (good fraction of the full moon size) meteors before, and the big ones still had tails, but maybe it was a simple perspective issue, as the ones I saw with tails were all on the horizon. It still scared me though and I'm a super tough guy whose not afraid of anything

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