kengr

This prompted by recently seen errors in books.

If you are writing SF involving interstellar travel, you need to know a few things about stellar types.

First off, the "colors" of stars used in descriptions by astronomers are *not* the actual colors. "Red stars" have more red in the spectrum, but are not what normal people would call red.
( Read more... )

Next biggie is that you have to consider not just stellar type (OBAFGKM) when deciding where to put a habitable planet, but also "size" (dwarf, giant, etc)
( Read more... )

Now we get to orbits. Both planetary and those of moons.
( Read more... )

This is a setiup I've been playing with for the Swarm shared universe.

In that universe humans were contacted by a confederation of aliens (who are scared silly of us) because There's an even *more* scary species moving down the galactic arm.

The Sa'arm are some sort of hive-mind, and nobody has been able to communicate with them. They discover a suitable planet ("Earthlike") land, and start harvesting all the resources in sight. This includes the inhabitants, if any.

They dig in *literally) and start producing more Sa'arm, and more ships. Eventually they've used up all the resources they can get at and abandon the planet. the ships they've produced go hunting more worlds to exploit.

The aliens (and humans) are often ignored, until they get in the way, or encounter a food harvesting party. If they attack, they get swarmed and killed.

Being pacifists, the member races of the Confederacy get slaughtered. so they contact us. We weren't their first choice, but that species suicided upon contact because they were *extremely* xenophobic.

Contact with us has a lot of problems. But a deal of sort is worked out. We get access to some technology, and ion return we go fight the Sa'arm (and try to build defenses on Earth).

Anyway, the Confederacy names systems for the jmajor inhabited planet by adding the suffix "-at" to the name of the world. So we live in the Earthat system. this is important...

So there are ships surveying space to look for planets we might colonize, planets the Sa'arm have colonized, and anything else that may be useful. The prelim stuff is done by ships popping out of hyperspace every so often and taking scan of the surrounding sky. These get combined to make 3D maps and decide which stars bear a closer look.

( Discovery of the system )

( system stats )

( A bit of local color )

Many years ago on the mailing list for the Traveller SF RPG there was a discussion on what people on a frontier world might use for power, especially in the early days.

There were many suggestions and one RTGs (Radioisotope Thermal Generators) resulted in a *lot* of back and forth with one camp basically going "nuclear! Aggh! Scary! Dangerous"

Things were at a bit of an impasse when it occurred to me to check some references. This resulted in a post along the lines of "Guys? They've had nuclear power long than we've had *writing*..."

That pretty much put things in perspective.

( Background )

Dec 14, 1972. At 2:54 pm PST, the last humans departed from the lunar surface.

Dec 14, 1972. At 2:54 pm PST, the last humans departed from the lunar surface.

How long before we return?

This is going to be looking at things from a combination of contemporary tech (and reasonable extensions thereof) and future tech based mainly on the Traveller RPG. It's probably easily adaptable to other backgrounds.

Humans need a few basic items. I'm going to list them in order of importance. That is, how quickly you'll be in trouble without them.

They are:
air
temperature
water
food
gravity

( Air )
( Temperature )

( Water & Food )
( Gravity )

S	M	T	W	T	F	S
				1	2	3
4	5	6	7	8	9	10
11	12	13	14	15	16	17
18	19	20	21	22	23	24
25	26	27	28	29	30	31

Entries tagged with space

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An unusual planetary system

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It's been 46 years

45 years...

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