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If the Earth were 100 pixels wide

distancetomars.com

201–210 of 216 posts

Re: If the Earth were 100 pixels wide

#201

Earlier quoted context omitted.

You didn't see this line? > Like that of Earth, the Venusian core is at least partially liquid because the two planets have been cooling at about the same rate.

Oh no, I'm very much aware of that reasoning. I offered a guess as to how/why someone might think the core is solid, not an argument for that conclusion. I included an easily digestible article which touches on all the same theory as the Wikipedia entry which was posted in "response" to it. Not all Internet communication has to be quippy argument. Also, the context of that citation: "By analogy with Earth, the core o…

Ah, I lost track of the thread and thought you were the initial poster who asserted that Venus was solid as if it was an established fact.

My apologies.

Re: If the Earth were 100 pixels wide

#202
Bug Report: I'm afraid this crashed between the Moon and Mars, just as some "you are travelling" text came in on the LHS and then it just went to whitescreen. Firefox 19.0.2 on Win7-64Home. In case you can catch it. (yeah ok so my laptop's not Linux, sue me!)

Re: If the Earth were 100 pixels wide

#203

This is the first time I've actually been able to comprehend the perspective of distances so big they don't mean much as a number. Thank you.

You can easily build an in 1:2e9 scale replica of the Solar System. You'll just need a 90cm sphere to use as the Sun, some 4-5 km of area do arrange things and a paquimeter for measuring the planets. At this scale, everything is just about as big/small as one can manipulate. Bu you won't be able to place the Voyager in there. For that you'll need a car and a road trip.

I think I remember a Bill Nye the Scoence Guy episode about this.

Re: If the Earth were 100 pixels wide

#204
post #50

It bothers me a little that they show the motion against a starfield like that -- the stars are so far away that they won't shift perceptibly even on a journey to mars. I mean, I don't have any better ideas, but given that the whole point is to give an idea of scale I wish they'd come up with something else. :)

How about you just imagine the ship is rotating on an axis for artificial gravity generation. Then, if you were looking out the window, you would see the starfield whizzing by. :-) Edited for smiley.

Sure, but then I have no sense at all of the distance traveled.

Re: If the Earth were 100 pixels wide

#205
post #168

One thing that's always gotten to me about this distance is what it means for communication latency. Mars is 20 light-minutes away. If we sent colonists, communication would be a 40-minute round trip. No phone calls home, no way to have a chat with friends or loved ones; at best they could send a message, and wait 40 minutes for a reply. That's far away.

if we could stretch a stick as long as the distance from earth to mars and use it to tap on mars ground something like a morse code to communicate, would that message be faster than a wifi message traveling at the speed of light?

No. As in air, the speed of sound in stick is still slower than the speed of light.

Re: If the Earth were 100 pixels wide

#207
post #112

Earlier quoted context omitted.

I'm more bothered by the authoritative fact that 'the timeline for a manned mission to Mars is the 2030s'. Says who, NASA? They're not the only ones trying to get there.

Does anyone else have a realistic more aggressive timeline?

Not that I know. SpaceX has considered sending an unmanned mission based on its Dragon platform in the 2018/2020 window which would prove a lot of technology that they could used for a manned mission later.

Re: If the Earth were 100 pixels wide

#209

Mars is a desolate, inhospitable rock floating in an immense void. I can't understand why people are captivated by the idea of living there.

It has water, mineral resources, a CO2 atmosphere plentiful enough to consider using it as an industrial feedstock, soil that we know you can grow plants in, a 24 hour day/night cycle, and enough sunlight to support crops. It also is "closer" to the rest of the solar system in terms of delta-v. If civilization expands into the solar system, Mars will be analogous to North America in the 16-20th centuries.

>It has water, mineral resources, a CO2 atmosphere plentiful enough to consider using it as an industrial feedstock, soil that we know you can grow plants in, a 24 hour day/night cycle, and enough sunlight to support crops.

Mars' atmosphere has only 20 times more CO2 than Earth's does, CO2 is not a rare chemical. We don't know enough about Martian soils to be sure that we can grow crops there.

>Mars will be analogous to North America in the 16-20th centuries.

I see this analogy around a lot and I've never cared for it.

1) All successful settlements of Europeans in the new world had some economic purpose for existing. The first few attempts to settle North America by English settlers were dismal failures until they discovered that they could grow valuable tobacco there. What is Mars' tobacco? We'd need a product that is cheaper to manufacture on Mars and ship back to Earth than to make on Earth. We need this because...

2) Mars is a vastly more hostile environment than the new world. It would have been possible to set up fairly small colonisation groups that were mostly if not entirely self-sufficient and thus didn't need to find economically sustainable products to sell to the home country in trade for vital supplies. In fact, later settlement in New England followed this pattern - many people paid for their passage and bought some land and only needed a few imported goods rather than the whole-sale re-supply that the earlier settlers in Virginia had required.

The minimum local knowledge and technology base was essentially simple agriculture at first, followed by some village-level craftsmen for simple tools and such. This meant that only a small fraction of the local economy had to produce goods for export because most things could be produced locally.

That is very far from being the case on Mars. The minimum technology base required to have a mostly independent colony on Mars is a substantial fraction of our entire tech base on earth. Even if we assume that high-complexity, high value-density things like computers and other electronics are imported from Earth that still leaves us with a lot that needs to be made on Mars. If we want to build another settlement on Mars from our initial base, can we do that?

Can we build the environmental management equipment needed? Pressure envelopes, power generation and distribution? Even something like light bulbs would be hard to do. Individually, all of these things are totally possible of but when you add them all together you start to require an awful lot of machinery to take with you.

The alternative of course is to keep supplying these things from Earth but without a sustainable source of goods to export back to Earth that isn't going to be sustainable.

3) The relative cost of transportation. Early settlers of the new world could use existing ships once they knew where to go. With Mars we know where to go but we don't have the ships. A moderately wealthy merchant could pay for the passage of his whole extended family to the Americas, even if the price drops dramatically that isn't going to be the case with a passage to Mars.

None of this is to say that I don't want to see permanent human settlement on other planets, but I think that comparing it to the settlement of the Americas is very unhelpful.

Re: If the Earth were 100 pixels wide

#210

Earlier quoted context omitted.

It has water, mineral resources, a CO2 atmosphere plentiful enough to consider using it as an industrial feedstock, soil that we know you can grow plants in, a 24 hour day/night cycle, and enough sunlight to support crops. It also is "closer" to the rest of the solar system in terms of delta-v. If civilization expands into the solar system, Mars will be analogous to North America in the 16-20th centuries.

>It has water, mineral resources, a CO2 atmosphere plentiful enough to consider using it as an industrial feedstock, soil that we know you can grow plants in, a 24 hour day/night cycle, and enough sunlight to support crops. Mars' atmosphere has only 20 times more CO2 than Earth's does, CO2 is not a rare chemical. We don't know enough about Martian soils to be sure that we can grow crops there. >Mars will be analogous…

> CO2 is not a rare chemical.

Never said it was. The point is, that you can just pull it out of the Martian air in industrial quantities.

> We don't know enough about Martian soils to be sure that we can grow crops there.

Many experts would disagree.

> All successful settlements of Europeans in the new world had some economic purpose for existing.

Yes, there would be a considerable initial economic barrier. But given the potential payoff, and that it's well within the budgets of current major powers, it's bound to happen. Just a matter of time and political will.

> Even something like light bulbs would be hard to do.

With current tech, we need a population of about 500 million to sustain a comparable technological infrastructure. This is going to go down with advances in technology, however.

> None of this is to say that I don't want to see permanent human settlement on other planets, but I think that comparing it to the settlement of the Americas is very unhelpful.

Because you're mistakenly using the analogy as a descriptor of difficulty. You're right that it's much more difficult in both an absolute and comparative sense. However, it's meant entirely as a descriptor of potential payoff. Compare the investment involved in establishing initial colonies and the value of interventions that resulted in British hegemony over North America with the value generated by the US economy. For English speaking western civilization, the payoff has been astoundingly huge.

I strongly suspect that there are people in China and other emerging powers who are well aware of this as well.

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