Hohmann Orbits and Sports Cars

I want to make this clear: SpaceX is not putting a Tesla into orbit around Mars. Not only would that be illegal by international treaty, but it would be technically impossible with the technology SpaceX currently possesses. What SpaceX is doing is putting a Tesla into a Hohmann Transfer Orbit between Earth and Mars that is very similar to the one we will likely use to get humans to that planet. Continue reading “Hohmann Orbits and Sports Cars”

Gale Crater Panorama

JPL posted a nifty panorama from Curiosity today.

There’s also a video description at https://www.youtube.com/watch?v=U5nrrnAukwI.

(Regarding the color of the sky, note the comment at the end of the video: “To aid geologists, colors in the image are white balanced so rocks appear the same color as the same rocks would on Earth.”)

The Color of the Sky

The color of the sky plays a central role in the first book of the series. This makes it important that I get it right. This it not as easy as one might expect. Obviously, no human eye has seen the Martian sky. We have imagery from our robotic probes on the surface. But what a camera sees is not what a human perceives. The truth is that we do not currently know what the Martian sky will look like to a person standing on the surface. We can, however, make an educated guess. Continue reading “The Color of the Sky”

Buried Ice

“The new study not only suggests that underground water ice lies under a thin covering over wide areas, it also identifies eight sites where ice is directly accessible, at latitudes with less hostile conditions than at Mars’ polar ice caps. “Astronauts could essentially just go there with a bucket and a shovel and get all the water they need,” Byrne said.”

Making oxygen

There is plenty of oxygen on Mars, just not in the nice O2 form that we need to breathe. Getting that requires some effort but will be worth it: oxygen is not the sort of thing we want to have to haul with us from Earth, particularly not for long-term colonization. The buzzphrase applied to technology that uses existing resources is In Situ Resource Utilization (ISRU), and this is what we are going to do, in one form or another. Continue reading “Making oxygen”

Mars Viewing

“In the summer of 2018, Mars will be closer to Earth than at any time since 2003. The Red Planet won’t be this close again until 2035…

At opposition, on a night with clear, steady air, even with a small telescope you should be able to see Mars’ polar cap of frozen carbon dioxide and water ice, along with darker and lighter regions on the planet.”

Skin-tight Suits

The human body needs protection in low-pressure environments (e.g the vacuum of space or Mars’ low atmospheric pressure). Without protection, gasses in the body expand and liquids sublimate away, basically making the normal function of bodily systems impossible.

Gas partial pressures and operating pressures of suits and habitats are huge topics that I am not getting into here right now. What I want to mention is something that is a little surprising: skin itself is gas-tight and does not need as much protection as one would guess. All that is required is mechanical compression in order for it to maintain its normal shape and function.