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NASA is lying. by - Thu, 12 Oct 2017 05:08:23 EST ID:rguyQexW No.57030 Ignore Report Reply Quick Reply
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>Earth is flat.

This picture proves the globe is a lie.

Prove Globe Earth in this thread.
27 posts and 20 images omitted. Click Reply to view.
Robert Dicke - Wed, 18 Oct 2017 09:00:54 EST ID:8caD3Z7Z No.57062 Ignore Report Quick Reply

This thread is great i hope it doesn't get lockismed
But they do change place
Henrietta Levitt - Sat, 21 Oct 2017 04:32:56 EST ID:xDCkxNvx No.57063 Ignore Report Quick Reply
hahaha what a retard. nb
Edwin Salpeter - Sat, 21 Oct 2017 06:20:12 EST ID:s63+/Nw4 No.57064 Ignore Report Quick Reply
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Considering the implications of a flat world or other fantastical shit and what it would affect/what else you'd have to change to make it work is a fun exercise.

Terry Pratchett's diskworld has light that moves about 40 mp/h due to the dense magical field.
The sun and moon are fairly close to the disk, a few thousand feet across, and move somewhat faster than their light, so it takes light awhile to catch up.

Since the sun or moon may outrun the light it emits depending on your position and its distance and angle, there may be positions on the disk where the moon/sun would, for a period, approach you faster than the light it emitted.
The number of suns you'd see (and what they might look like) at various times, how fast they'd appear to move, etc all become more interesting the closer you look.

Pratchett of course solved all this. "This doesn't cause problems."
Carl Seyfert - Sat, 21 Oct 2017 13:48:11 EST ID:+MrWEJ1z No.57065 Ignore Report Quick Reply

then why do we have pictures of the continent
Fritz Zwicky - Sat, 21 Oct 2017 17:59:00 EST ID:unNII3om No.57066 Ignore Report Quick Reply
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Why can't OP post something of value, like a dissertation disproving the Coriolis effect, instead of low-grade pictures and regurgitations?

Because he's wrong and a troll.

You don't understand galactic scales; Relativity is a bitch thread by Kiyotsugu Hirayama - Thu, 04 May 2017 18:10:19 EST ID:unNII3om No.56931 Ignore Report Reply Quick Reply
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So imagine you have two cannons firing their cannon balls away from each other, and their muzzle velocity is the speed of light.

You'd think the relative speed of one cannon ball to the other would be 2x the speed of light, right?

Nope. The equation for relative speed between two objects looks like this:


Where v1 and v2 are the speeds of the two cannon balls and c is the speed of light.

So as the velocity of the cannon balls approaches the speed of light, their own speed doesn't matter and the limit of light speed is dominant. Relative speed of 2x speed of light is thus impossible.

Or in other words: wat.

You guys got some other relativistic mind-blowers?
17 posts and 2 images omitted. Click Reply to view.
Maximilian Wolf - Sat, 29 Jul 2017 13:55:31 EST ID:+G8ef2Iy No.56989 Ignore Report Quick Reply
Light isn't really devoid of mass, it simply has no rest mass. Using the concept of mass you are is a bit of an outdated/antiquated concept. As it relates most specifically to this situation, the difference between a particle or an object's mass and rest mass is that it takes into account what we learned about mass and energy through the lens of Special Relativity. Things that are accelerating (acceleration is an important distinction to make here because in space it's not really possible to establish fixed frames of reference and whatnot) have more mass than things that are not accelerating. Until the acceleration approaches velocities very near the speed of light, however, the difference in mass is pretty much infinitesimal and therefore pretty much negligible.

The guy that responded to you is right, light does travel at velocities less than what the speed of light is measured at in a true vacuum. However, most of known the observable universe where otherwise nothing appears to exist is actually a false vacuum. A true vacuum is characterized by the lowest possible energy state, but a false vacuum just happens to be the local minimum (keeping in mind local can encompass some pretty vast sectors of space). If I remember correctly, in areas that there appears to be nothing and you'd expect it to be vacuum, there are actually photons left over from the Big Bang (hence being able to measure the Cosmic Microwave Background Radiation).

As for why the speed limit couldn't be higher... You just have to think about it for a minute. All measurements, whether they're of speed/velocity, distance, or what have you, are relative to other measurements. That's why we establish a basic unit that we can more or less view as arbitrary that we can use to orient ourselves and make sense out of the measurements we make. The speed of light just is what it is. What numbers and measurements we assign we to it are entirely for our benefit and as long as you're decent at math it's pretty easy to manipulate things so that the numbers could be higher or whatever.

But, what you meant more specifically is why the speed of light not able to be faster, not why our n…
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William Lassell - Wed, 02 Aug 2017 17:06:58 EST ID:uSMmLmww No.56992 Ignore Report Quick Reply
i am going to think about your words, max. ed's and joseph's too, thanks fellas.
Harlow Shapley - Wed, 02 Aug 2017 20:26:06 EST ID:d6k0JkjC No.56993 Ignore Report Quick Reply
TLDR: Because light is a self-propagating electro-magnetic wave per Maxel's Equations.

William Hartmann - Mon, 11 Sep 2017 13:15:57 EST ID:kRyBQtrI No.57015 Ignore Report Quick Reply
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But you're helpful otherwise.
Fred Hoyle - Sun, 15 Oct 2017 20:38:36 EST ID:lQ9q0NgK No.57061 Ignore Report Quick Reply
>causal violations are not a problem in relativity. They are in fact expected and on multiple levels
I would disagree with this sentiment. Although violations of causality certainly may be possible, I would argue that the general (excuse the pun) theories of S.R. and G.R. rely heavily on the notion that causality is inviolable. In example of separate observers witnessing events, you are confusing causality with simultaneity. This is only possible for events that are causally separated (spacelike). If events can be perceived as simultaneous in some reference frame S, then they must be causally separated if there is nonzero distance between them (in S). Special relativity and causality allows you to boost to some frame S' with nonzero velocity relative to S such that the events occur out of order, however no matter how fast you go in S', the events will never occur in each other's light cone without exceeding the speed of light, and therefore cannot be causally related. tl;dr: violating simultaneity is not violating causality.

>There's a limit to the rate of causality, that makes the speed of light, but causality itself is not necessarily inviolable
Central to relativity is the notion that the speed of light is the same in any reference frame and cannot be exceeded. As you alluded to here, causality is defined by the speed of light (if event b occurs before light from event a could have reached it, then a cannot have caused b because the information that a has occurred will reach b after b happens). Therefore in order to violate causality, you must exceed the speed of light, which is forbidden in relativity.
With that said, that paper is certainly an interesting read, but it is investigating possible mechanisms of causal violation that would modify or extend the existing theories of relativity. It is well known that quantum mechanics and general relativity don't get along, and thus a theory of "quantum gravity" will have to violate some well established principals, but this is just the nature of science. I'm trying not to argue that causal violations are impossible, just that the notion that causal violations are expected by conventional relativity is …
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Hey Nerds by Antony Hewish - Sun, 23 Jul 2017 18:26:46 EST ID:Fbpr3rrr No.56982 Ignore Report Reply Quick Reply
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I was wondering why you guys post here? Aren't these boards ungodly slow? Wouldn't it be easier for you to just go to an actual forum for space discussion? Why wait so long for a reply from some drug addict about stars or whatever when you can probably get better information more quickly from somewhere else?

Not judging, just genuinely curious
11 posts and 1 images omitted. Click Reply to view.
hokusai - Sat, 19 Aug 2017 11:26:42 EST ID:LIO8YU+/ No.57003 Ignore Report Quick Reply
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havent read the thread but i dont thing faster than light travel is possible the way it will be done is not by moving objects but consciousness around space outside time thats why i post here and not in a science forum
Margaret Burbidge - Sun, 20 Aug 2017 05:14:34 EST ID:PovkMdyu No.57005 Ignore Report Quick Reply
Is there really any faster forum than a chance? I mean besides ones filled with terms like "social media"
Kip Thorne - Thu, 12 Oct 2017 14:09:23 EST ID:KX/DxO6v No.57048 Ignore Report Quick Reply

speed exists in relation to predetermined points on a coordinate system
James Elliott - Thu, 12 Oct 2017 16:50:14 EST ID:unNII3om No.57050 Ignore Report Quick Reply
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Space has no inherent coordinate system dude. This is like one of THE realizations of relativism.
Kip Thorne - Thu, 12 Oct 2017 19:57:11 EST ID:KX/DxO6v No.57052 Ignore Report Quick Reply

yep, very good. now let's break down relativism: that which is relative [to a given frame of reference]; i.e. you make up your own system as an observer, which will be different from every other observer's system. an object in motion in relation to another object in motion can only have a determinate speed (if we are serious about this conversation we should start using the term velocity, actually) within a predetermined system.

SpaceEngine/Universe Sandbox Thread! by Cosmobud - Mon, 18 Sep 2017 22:41:08 EST ID:1NT/Ijtb No.57022 Ignore Report Reply Quick Reply
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Why isn't there one? Post your awesome finds, explosions, super novae, whatever! OP image will be from Universe Sandbox, I'll post another from Space Engine.
Cosmobud - Mon, 18 Sep 2017 22:52:10 EST ID:1NT/Ijtb No.57023 Ignore Report Quick Reply
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Walter Adams - Fri, 22 Sep 2017 19:44:24 EST ID:3hL9HQte No.57026 Ignore Report Quick Reply
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tfw no space engine VR support yet
Harlow Shapley - Sat, 23 Sep 2017 02:26:00 EST ID:ur3W8pPa No.57027 Ignore Report Quick Reply
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Not sure where this was.

Astronomy Club by Ejnar Hertzprung - Wed, 13 Sep 2017 12:02:26 EST ID:dWt9NTso No.57017 Ignore Report Reply Quick Reply
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I'm trying to make an astronomy club but I don't know what it would be about or what to do. Everyone else who likes astronomy are just shy like me and we all refuse to talk. Logically I know that the club show be at night because astronomy but what do you think I should do at such a club. Thank you
Dr. Mario !gWLn19/oKs - Thu, 14 Sep 2017 21:49:37 EST ID:9UftK+wR No.57018 Ignore Report Quick Reply
definitely smoke weed together. lots of weed. thats a given
Jocelyn Bell - Sat, 16 Sep 2017 12:26:08 EST ID:2H001r1f No.57020 Ignore Report Quick Reply
Alrighty !
Karl Swarzchild - Thu, 21 Sep 2017 10:46:21 EST ID:sywMqW4i No.57025 Ignore Report Quick Reply
>the club should be at night
>what do you think I should do at such a club

well gee, ill tell you what i think
Galileo Galilei - Sat, 23 Sep 2017 21:07:05 EST ID:7bk1TGPO No.57028 Ignore Report Quick Reply
maybe you could look at stars and talk about them

Cassini by Edward Barnard - Wed, 26 Apr 2017 09:23:19 EST ID:rmFM08wB No.56925 Ignore Report Reply Quick Reply
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No Cassini thread? Think we'll find anything we weren't expecting in dem rings?
5 posts and 2 images omitted. Click Reply to view.
Alan Guth - Thu, 13 Jul 2017 18:48:31 EST ID:unNII3om No.56978 Ignore Report Quick Reply

Aw man, what a downer.
George Herbig - Fri, 14 Jul 2017 03:51:43 EST ID:nRjWggLk No.56979 Ignore Report Quick Reply
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Paul Goldsmith - Wed, 19 Jul 2017 14:04:24 EST ID:yxm0fECC No.56981 Ignore Report Quick Reply
shouldn't a bunch of scientists be able to at least count properly?
John Wheeler - Thu, 14 Sep 2017 23:31:42 EST ID:CZNpyEE2 No.57019 Ignore Report Quick Reply
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Goodnight sweet prince
Charles Messier - Mon, 18 Sep 2017 15:15:40 EST ID:HLehYNUW No.57021 Ignore Report Quick Reply
Fraisier Cain is that you?

Other worlds by William Herschel - Tue, 08 Nov 2016 04:19:55 EST ID:FFHdMrF/ No.56642 Ignore Report Reply Quick Reply
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Do you think we will be capable to leave our solar system one day? Or that getting even to the closest star is impossible.
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Subramanyan Chandrasekhar - Sat, 10 Jun 2017 16:28:00 EST ID:unNII3om No.56952 Ignore Report Quick Reply

Just an interesting consequence of relativity: As you approach the speed of light, time slows down. While the trip might take decades or centuries from our perspective, it can take significantly less from the perspective of the travelers. With an efficient enough vessel, traveling to Alpha Centauri can theoretically be done without generation-ships.
William Lassell - Fri, 23 Jun 2017 17:10:24 EST ID:iClpwVzv No.56958 Ignore Report Quick Reply
Even without time dilation, Alpha Centauri isn't that far.
If we could accelerate at 1g halfway, then decelerate at 1g the other half, it would only take 6 years without time dilation (3.5 years with dilation).
That kind of acceleration is a tall order though.
At only one tenth of a g, it's still only about 13.6 years to an outside observer.
Google "relativistic star ship calculator". I like the one from convertalot.com
Stephen Hawking - Fri, 25 Aug 2017 23:54:14 EST ID:p1UqQx6T No.57012 Ignore Report Quick Reply
The budget is what makes it impossible. As such, humans don't deserve to leave. Money and the idea of it holds us back more than people will ever realize. If man would just stop being selfish and/or trying to control others, we would be so far ahead. Those that want to waste away would be allowed to and those that want to do something great would be able to, because without money, the only thing holding you back would be yourself. In this life, it's both other people and money.
Clyde Tombaugh - Fri, 01 Sep 2017 17:36:46 EST ID:unNII3om No.57014 Ignore Report Quick Reply

Only that doing anything of the high-tech sort demands a huge cooperation between people. The guys who build the constituent parts of the rockets, how do they eat without bartering something for their work? How do the scientists eat without bartering something for their work?
Verty - Wed, 13 Sep 2017 01:08:39 EST ID:VRvuffr/ No.57016 Ignore Report Quick Reply
We won't be able to go anywhere important until we figure out how to fold space-time, which some aliens already have as I saw.

Fucking ECLIPSE thread! by Irwin Shapiro - Sun, 20 Aug 2017 15:50:15 EST ID:KgS57XEk No.57006 Ignore Report Reply Quick Reply
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Come on! Get excited for this!

I got a cheap solar filter sheet and put it in front of my 300mm lens. Which is plugged into a 2x teleconverter. 600mm to grab the eclipse.

Took some test shots today and got to see some sunspots! Which are freaking cool (well, RELATIVELY cool...LOL!)

Post eclipse shit here people!
1 posts omitted. Click Reply to view.
Bruon Rossi - Mon, 21 Aug 2017 20:45:32 EST ID:bxNkmvEL No.57008 Ignore Report Quick Reply
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Nope. Just one big flat Earth.
James Christy - Tue, 22 Aug 2017 02:54:41 EST ID:nHAT7Ro+ No.57009 Ignore Report Quick Reply
Can you share your footage pretty please with dank moon rocks on top?
Russel Hulse - Tue, 22 Aug 2017 19:47:49 EST ID:unNII3om No.57010 Ignore Report Quick Reply
Didn't see shit.

Born too north and east to experience it, and it's like ages until the next proper eclipse over my country.

Hope you niggers enjoyed it, and avoided being like wow eclipse well whatever dude I wonder what's on youtube?
Bruon Rossi - Thu, 24 Aug 2017 15:04:53 EST ID:cP2dPTDR No.57011 Ignore Report Quick Reply
Just got back from watching it in Casper, WY. It was amazing and felt so unearthly. It's really weird to look up in the sky and see something so different. You can't help but laugh and be in awe at the big ring of ghostly white light in the sky.

The difference between 99% and totality is unreal. Until that last bit of sun is covered, it's neat, but it doesn't seem like that big of a deal. Then totality clicks in and the whole character of everything changes. If you missed seeing this one, def try to get to the one that runs from Texas to Maine in 2024.

Also, for the next one, make sure to check out the shadows on the ground as you approach totality. The dappled light/shadow under a tree acts as hundreds of pinhole projectors. You'll see hundreds of projections of the moon passing in front of the sun. The patches of light will all turn fishscale-shaped. It's pretty great.
Alan Guth - Tue, 29 Aug 2017 20:20:56 EST ID:fsTyqOA+ No.57013 Ignore Report Quick Reply
Was down in Greenville SC visiting my parents for it. Truly surreal, is the only way I can describe it. The most radical part was how the sun was still too powerfully bright to look at until absolute totality.

Down in Greenville totality lasted for what felt like a minute exactly. It is the most bizarre thing, it was getting visibly dimmer on the ground, and approaching totality it was near twilight. Up until exact totality though, you cant look at the sun. It was just that bright still. Then, totality, saw some Baileys Beads, even saw some sun snakes (atmospheric turbulence you can see on sidewalks as totality approaches).

Once totality was over, the sun came to the other side of the moon, and BAM, bright as fuck again.

It gave me a respect for how fucking powerfully bright that big plasma ball really is.


Perseid meteor shower! by Johann Encke - Wed, 31 Jul 2013 11:29:34 EST ID:evrPe8Vs No.51233 Ignore Report Reply Quick Reply
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Anyone else gonna observe this beautiful event?

Incase you haven't heard from AUG 12th to the 13th between 10:30PM and 4:30 AM, The sky's gonna light up with massive fireballs brighter than Jupiter.
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Wilhelm Beer - Sat, 27 Aug 2016 04:13:56 EST ID:Y/YEbfJF No.56331 Ignore Report Quick Reply
I actually got to see it on the night of the 12th. I was on the east coast in outer banks on vacation. Was smoking js and sipping coladas with a pretty girl i just met. Walkin back to my house we saw one right above our house direction wise. Which was freaking awesome cause it looked like a ufo or something. And you can see lots of stars out there on the coast. We saw about 5 in an hour but we werent even looking. They were super low too
Edwin Hubble - Sat, 01 Oct 2016 12:47:50 EST ID:r8ZHfF3E No.56504 Ignore Report Quick Reply
It was considerably longer last year and it was visible in the city.
We must have been in the outskirts of the geminid
Gerard Kuiper - Wed, 09 Aug 2017 18:42:14 EST ID:/VSfubHK No.56997 Ignore Report Quick Reply
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Anyone going to observe this year's Perseid meteor shower?
Wilhelm Beer - Tue, 15 Aug 2017 00:15:44 EST ID:uuw9w7i5 No.57000 Ignore Report Quick Reply
I did not know this was annual

you failed me Sagan
William Lassell - Sat, 19 Aug 2017 22:02:46 EST ID:dG4sHLwu No.57004 Ignore Report Quick Reply
I caught sight of seven or so. Too bad it was too cloudy most of the time. Really want to go out of the city for next year.

Books! by William Lassell - Fri, 28 Jul 2017 19:52:00 EST ID:CtWYD6pG No.56988 Ignore Report Reply Quick Reply
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Can you recommend me soke books on the universe in general. Like books on astrophysics , black holes or planets. Thank you.
Bernhard Schmidt - Wed, 16 Aug 2017 23:44:30 EST ID:nRjWggLk No.57001 Ignore Report Quick Reply
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The Night Sky. by George Herbig - Thu, 06 Jul 2017 19:26:48 EST ID:5rTlMpAv No.56975 Ignore Report Reply Quick Reply
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It was late august and the skies were perfect out in the cornfields of Nebraska,
It was the darkest I've ever seen, I couldn't see my hand in front of me, let alone the stalks.

After about half an hour of stumbling through the field trying to find my spot, (a clearing that my friend used to grow weed) I finally stumbled upon a small trail that led to the clearing.

In the clearing there was a trailer, a lawnchair, a cooler and a telescope. I turned on my lantern and went into the trailer. There were stalks of weed hanging on clotheslines as well as a few pills scattered on a table with a note that said "help yourself", with a winky face alongside a condom.

I thought it was a prank, but I thought I might as well so I took the pills all at once and shaved off a nug branch of uncured weed and smoked it the best I could. Anyway I got out my telescope and used my night-sky app on my phone to find the planets (yeah I know, I'm lazy).

As I was focusing in on Saturn I noticed my vision started to blur a bit. I thought at first the lense was just out of focus but I soon found that something was happening. I continued my search anyway, the best I could until I could no longer keep up.

I decided to just chill on a tarp and watch the stars instead, see If I could make out the ISS and other satellites. I started thinking about how those stars are actually clusters of galaxies that are probably gone, it made me sad but then I felt something.

My dick was hard as a rock., On top of that the stars wouldn't stay still. It was bothering the fuck out of me until it didn't. I started to see my own constellations, they turned into titties and even full on line-porn.
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Joseph Taylor Jr. - Sun, 23 Jul 2017 22:19:45 EST ID:s0XmRX5r No.56983 Ignore Report Quick Reply
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havent heard that one before

oh cool by Pierre-Simon Laplace - Tue, 18 Jul 2017 14:04:36 EST ID:T69KfNA1 No.56980 Ignore Report Reply Quick Reply
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imagine what planet discovering when listening to thids

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