Recent content by bolide

"He's no fun--he fell right over!"

The point was just that Earth is externally heated, and so does not serve as an example of this idea. I probably should have just stated it like that.

Evaporation cools the water, but where does that heat energy go? Into the atmosphere, right? So how is there going to be a net cooling effect?

Assuming we are talking about the environment at the planet's surface, this argument seems to fall on the horns of a dilemma. Either the hot core makes a significant thermal contribution to the habitability of the surface environment, or it does not. If it does not, then the initial premise is...

Mars trip doesn't have that problem. Just like Mars and Earth and everything else being dragged by the Sun, so is your spaceship. It's like throwing a ball back & forth in a moving train car. You don't have to throw harder in the forward direction to "catch up" with the train's motion. Your...

That's my understanding. This spiral has not been seen as yet in any observational data. They created a computer simulation of the Oort cloud, and found a spiral in the simulation.

Logically, this resembles a certain retort to someone who complains that God didn't answer their prayers: "Yes, He did--and the answer was No."

The problem is that our understanding of events presupposes Absolute Time, that is, the idea that a given moment (like "the present time") occurs instantaneously throughout the universe. If we observe today the explosion of a star that is 1000 light years away, what event on earth is that...

What is 'now'?

The idea of this species, which has barely had language for a couple hundred thousand years, living in this not-so-very-stable universe, speculating about "the next million years" is amusing.

Agree with everything you said except "The cost of orbiting mass is now trivial," at least as applied to the ISS. Nothing trivial about having to constantly rotate astronauts up & back. The only sensible fate for the ISS is to let it fall, and even that we are now seeing is problematic.

Looks like a tradeoff between how much fuel you can carry and how long you want the astronauts to be traveling.

I'll stand corrected. So 5½ hours @ 1g up to speed, and another 5½ @ 1g to stop. But what about the energy requirements for accelerating the mass of a suitable spacecraft for 11 hours @ 1g?

No, the limit is the endurance of the human body in the conditions produced by the trip. How do you get to 400,000 mph?

The ISS is not an "interstellar ship." It's not even capable of leaving Earth orbit. Our telescopes are barely "interstellar," never mind our spacecraft.