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Not long ago, the center of the Milky Way exploded

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Re: Not long ago, the center of the Milky Way exploded

#81

Post by mcguire »

SimbaOnSteroids wrote: post #78
frogpelt wrote: post #67

Earlier quoted context omitted.

And yet few have ever heard this Larry while Millard Fillmore maintains the distinction of being the president with the coolest name. If only Spiro T. Agnew would have made it.

Larry Niven's most famous work Ringworld, inspired both of the massively popular games Magic the Gathering, and Halo: Combat Evolved. I suspect that Niven and Fillmore have roughly equal name recognition, though, simply by the nature that Niven is still alive, and appears to be more consequential long term.

Magic? What is the link there?

Re: Not long ago, the center of the Milky Way exploded

#82

Post by chowells »

mcguire wrote: post #81
SimbaOnSteroids wrote: post #78

Earlier quoted context omitted.

Larry Niven's most famous work Ringworld, inspired both of the massively popular games Magic the Gathering, and Halo: Combat Evolved. I suspect that Niven and Fillmore have roughly equal name recognition, though, simply by the nature that Niven is still alive, and appears to be more consequential long term.

Magic? What is the link there?

Nevinyrral's Disk, at a minimum.

https://gatherer.wizards.com/Pages/Card/Details.aspx?multive...

Re: Not long ago, the center of the Milky Way exploded

#84

Post by SimbaOnSteroids »

mcguire wrote: post #81
SimbaOnSteroids wrote: post #78

Earlier quoted context omitted.

Larry Niven's most famous work Ringworld, inspired both of the massively popular games Magic the Gathering, and Halo: Combat Evolved. I suspect that Niven and Fillmore have roughly equal name recognition, though, simply by the nature that Niven is still alive, and appears to be more consequential long term.

Magic? What is the link there?

The entire concept of mana being generated from land.

Re: Not long ago, the center of the Milky Way exploded

#85

Post by whatshisface »

AnIdiotOnTheNet wrote: post #49
snowwrestler wrote: post #44

Earlier quoted context omitted.

I find it very hard to imagine a human civilization on Mars being self-sufficient. Getting there is not the hard part. The ecology of self-sufficiency is not something we understand currently, even on Earth.

Indeed. If we were serious about colonizing mars we should first colonize portions of the earth that are currently uninhabitable (self-sufficiently). They all are much easier to get to and have significantly more favorable conditions than Mars, but for some reason no one tries to make the Arctic self-sustaining or wants to build a deep ocean colony.

We already have experiments being performed on ocean floor labs and arctic outposts. Building habitats on remote places on earth and building them in space are not mutually exclusive, in fact the former is part of the space program today. (Astronauts are trained on the ocean floor before being sent to the ISS).

Re: Not long ago, the center of the Milky Way exploded

#86

Post by jerf »

mcguire wrote: post #81
SimbaOnSteroids wrote: post #78

Earlier quoted context omitted.

Larry Niven's most famous work Ringworld, inspired both of the massively popular games Magic the Gathering, and Halo: Combat Evolved. I suspect that Niven and Fillmore have roughly equal name recognition, though, simply by the nature that Niven is still alive, and appears to be more consequential long term.

Magic? What is the link there?

While Larry Niven is most famous for his hard science fiction, in the traditional sense of the term, he also has a fantasy universe, with a decent introduction at https://en.wikipedia.org/wiki/The_Magic_Goes_Away In this universe, magic is a finite quantity, which gets used up. The modern world is mundane not because magic is impossible, but because it was all used up.

(It would be interesting if he ever wrote the story set in this universe, after the modern times, in which humanity gets out to space, and, uh, hey guyz, magic kinda... works out here... what the heck? It wouldn't necessarily take long to figure out what the deal is with Earth being a dead zone, but it would cause some interesting political upheaval as suddenly the sparse space colonies that nobody thought were worth anything and barely even worth the effort became industrial powerhouses as the only place where magic works... and not just the tame, dying magic of Niven's stories, but the original wild, abundant magic the stories claimed Earth initially had.)

Re: Not long ago, the center of the Milky Way exploded

#87

Post by jerf »

ljf wrote: post #41
FrameworkFred wrote: post #35

Given that we're able to aim telescopes at things that are billions of light years away, I wonder how close we are to being able to see the reflection of such a thing when it actually happens on some celestial body 3.5 million light years away.

I remember as a child thinking I had fixed time travel (in a very limited sense) when I wondered why we didn't just stick a bunch of mirrors far far away, and then aim them back at the earth and use telescopes to look back at the dinosaurs etc. While that wouldn't work for heaps of reasons, I like your idea. I guess the issue would be discerning 'when' such a thing happened, and finding the right item to look back at…

You need natural mirrors, because as others have pointed out, they have to already be there, you can't get ahead of the light to put them there.

It has been suggested that black holes could provide this mirror, but it requires resolving not just something the size of Earth, but something much smaller, at a distance of 30 million light years +. Unfortunately you actually start hitting up against the limits of spacetime's resolution itself fairly quickly. But at least in principle, it is possible that some lucky photon has bounced off a dinosaur, and has traveled all the way out there, and all the way back to Earth, just now, that if you knew where to look in the sky, perhaps such a photon might even enter your eye now. Or perhaps there is some human out there who really has "seen" the dinosaurs. But you'd never really know.

Re: Not long ago, the center of the Milky Way exploded

#88

Post by Negitivefrags »

frogpelt wrote: post #67
dwoozle wrote: post #59

Earlier quoted context omitted.

Larry Niven is still relevant while Millard Fillmore is not.

And yet few have ever heard this Larry while Millard Fillmore maintains the distinction of being the president with the coolest name. If only Spiro T. Agnew would have made it.

I have heard of Larry Niven and never heard of Millard Fillmore.

Being outside the US I never covered past US presidents in school.

Re: Not long ago, the center of the Milky Way exploded

#89

Post by s1artibartfast »

yourapostasy wrote: post #21
nerdponx wrote: post #3

They said the flare lasted 300,000 years, but how quickly does something like this start? How fast does it go from "nothing" to "full strength"? Also if there was any form of life orbiting a star in the path of this flair, is it safe to assume that said life is no longer alive? At least if that life resembles us in its tolerance (or lack thereof) for radiation.

> Also if there was any form of life orbiting a star in the path of this flair... Based upon a couple other articles I read [1] [2], it sounds unlikely there were other galaxies or smaller structures in the path of this flare. I only see references to a very directional cone at the poles of the Milky Way, and the cone only intersects a trail of gases left behind by the Magellanic Stream. Were there somehow orphaned p…

There very likely were thousands of stars in the paths of the jets as they passed through the galactic bulge at the center of the galaxy. Our galaxy gets thicker in the galactic center and the bulge is 3000+ light years thick and contains an estimated 10 million stars.

Re: Not long ago, the center of the Milky Way exploded

#90

Post by rjf72 »

AnIdiotOnTheNet wrote: post #49
snowwrestler wrote: post #44

Earlier quoted context omitted.

I find it very hard to imagine a human civilization on Mars being self-sufficient. Getting there is not the hard part. The ecology of self-sufficiency is not something we understand currently, even on Earth.

Indeed. If we were serious about colonizing mars we should first colonize portions of the earth that are currently uninhabitable (self-sufficiently). They all are much easier to get to and have significantly more favorable conditions than Mars, but for some reason no one tries to make the Arctic self-sustaining or wants to build a deep ocean colony.

There are specific reasons for the things you're talking about.

For Antarctica (which is not the Arctic, but I assume what you meant - Scandinavia is quite self sustaining!) you have the Antarctic Treaty System. [1] The TL/DR there is that pretty much every form of development in Antarctica is illegal, and you're not allowed to leave any waste whatsoever. When an antarctic researcher is on a mission, they're required to bottle up their feces/urine and bring it back to base. The urine is processed and then returned to the sea. Feces are generally returned to the host nation for local removal. Mining and other industry is expressly prohibited.

But something even more interesting is comparing Antarctica to Mars, even ignoring the treaty system. Mars has two big things going against it: radiation, and a negligible atmosphere. That means you need to limit your exposure outside, and when you do go outside it needs to be with appropriate equipment and clothing. Of course the exact same requirements also hold true of Antarctica, though to a lesser degree.

But it also has quite a lot of things going for it. Mars day/night cycle is identical to Earth and it even has near identical seasons owing to a near identical tilt. Antarctica, by contrast, has what is basically a 6 month long day/night cycle. And the weather is absolutely vicious. There are genuinely violent snowstorms, as well as temperatures that average -30F, and much lower on the inner areas away from the coasts. By contrast temperatures on Mars (depending on what part of the planet you're on, and when) can get right balmy. Summer on the equator? It gets up to about 70F, though the nights are still extremely cold owing to no atmosphere.

But the snow storm part is one of the more interesting comparisons. Maybe the biggest thing is "The Martian." The key plot event there was a terrible sand storm on Mars ravaged their base and setup the plot for the rest of the film/movie. The Martian itself is a hard sci-fi book. This is one of the very few things that was intentionally faked. The worst sandstorm on Mars would feel like a slight breeze owing to the negligible atmospheric pressure. Think about that - a hard sci-fi book had to resort to fantasy to create a meaningful disaster!

There's a lot more to say/compare as well, but this is already getting a bit too long. Suffice to say, these issues are extremely counter-intuitive, but also extremely interesting to explore!

[1] - https://en.wikipedia.org/wiki/Antarctic_Treaty_System

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