Friday, June 22, 2018

Martian Shelter 1

People are finally giving serious thought to the possibility of living someplace off the Earth. Thought we’d take a look at what those new house designs might look like. Seeing what might be available, once we get to go. We’ll start with Mars, since everybody’s so excited about the possibility of getting there in the next decade or so.

The first shelters will be shipped to Mars from Earth. Maybe they’ll be shipped ahead of time and need to be activated when humans arrive, but probably, the shelter will arrive with them. After all, it worked on the moon, though the shelter in that case was a piece of space ship. It served the purpose for the short time that anybody was there. They even brought part of it back with them. Kind of like living in your car, do you suppose?

So here’s some of the ideas that are floating around for housing on Mars:

1. One suggestion for an early shelter is an inflated balloon-type structure. Think of some kind of thick, air-tight fabric that could be unfolded and laid out in the desired position, hooked up to a supply of air, and blown up. The fabric could be augmented with support structures, and finally, the entire thing could be covered with sand for extra insulation, both from thermal variance and radiation. The average Martian temperature is -80° F, plus the air is mighty thin, so you have to have plenty of insulation. You’d probably have to tie this puppy down before you started inflating it, or risk it floating away in the breeze, but I’m sure the instructions would point that out.

After reading about this proposal, I’m left wondering how the door would be added. It would have to be an air lock, or else opening the door really would mean you’d let all the heat out! I keep thinking an airlock would be made of metal, but perhaps they could fashion them out of plastic or something similar, and they could be added to the ‘balloon’ before it left Earth. Would they only put one door in this balloon, or would they add a back door, too? And who is going to shovel all that sand on top and around? Would they dig a hole in the ground to hold the balloon? Sounds like a lot of hard work, if the ground is frozen or otherwise solid. What’s the circumference of this balloon? Will they have to walk (or drive) all over it to get the sand distributed?

I suppose it has possibilities, but it really sounds an awful lot like a fixer-upper.

Well, phooey. We’ve only looked at one possibility, and I’m out of words. Can’t make these things too long, or so they tell me. We’ll have to continue this search for a new home next week, because there are definitely other possibilities. But don’t get your hopes up; I didn’t see a single split-level ranch on the list.

Thursday, June 7, 2018

A Girl’s Best Friend... a Diamond... Planet?

55 Cancri-e was discovered in 2004, circling a star not that far from us. It was called a “super-Earth”, because it was rocky like the Earth and larger. Its radius is twice Earth’s, making its mass about 8 times ours, while it speeds around its star in only 18 hours. To do that, it has to be so close to the star’s surface that the planet’s surface reaches temperatures around 3,900° F (2,100° C). {Just a little warmer than Nebraska in August.}

{By the way, the ‘e’ of 55 Cancri-e means this was the 4th planet found in orbit around this star. (The star itself is designated A.)The other 3 reside even closer. Where does the star end and planet(s) begin? More recently, a 5th planet - ‘f’ - has been discovered, with a year lasting about 261 Earth days.}

If 55 Cancri-e had a planetary chemistry similar to Earth’s, the temperature and mass might mean it was covered with oozing ‘supercritical fluids’ (gases at such a high pressure they would act more like liquids). So it was imagined, at one time. But further study has revealed that it has a planetary chemistry far different.

For one thing, it apparently has no water on it at all.

Astronomers felt 55 Cancri-e was probably composed almost exclusively of carbon (diamond & graphite), iron, silicon carbide and possibly silicates. More than 1/3 of its mass could be pure diamond, which would be more than the entire Earth. Try sticking that into an engagement ring!

However, the diamond part was probably not just one big chunk. They thought the planet’s surface was covered in graphite and diamond rock, rather than our familiar water and granite. Actually, the Earth has far, far less carbon in comparison. So they tried to figure out what that difference meant. This different planetary chemistry could mean 55 Cancre-e could have had a very different thermal evolution than Earth and strange plate tectonic processes, which would mean bizarre types of volcanism, mountain formation and seismic activity.

But a new analysis indicated that 55 CancriA (the star in question) had more oxygen than previously thought. That might mean 55 Cancri-e might not have quite as much carbon as they had thought. Or it might mean nothing. The processes of star and planet formation are not fully understood, but it is known that the composition of a planet does not always match that of its parent. So the studies continued.

In 2016, observers detected hydrogen, helium and possibly hydrogen cyanide in ‘e’s atmosphere. In 2017, they decided there might be a global ocean... made of lava, so no skinny dipping. And that e’s atmospheric pressure was about 1.4 bar, so a slightly thicker atmosphere than ours.

If all this sounds familiar, well... We visited the 55 Cancri system on or about 6Sept2017, in the 2nd episode of my ‘Weird Planets’ series of blogs. But I think I found more details this time, so hope you enjoyed ‘catching up’.

Oh, yes, in July 2014, the International Astronomical Union launched a process for giving ‘proper’ names to some exoplanets and their host stars. The name selected for 55 CancriA was Copernicus, and e was named Janssen. (Yes, all his known siblings got named, too.)