Firefly's premiss is that "The Earth That Was" could no longer be lived on. People were sent to live on other planets that were terraformed. Terraformation is a common premiss in astronomy science fiction. Another common plot in science fiction and any suspense driven genre is "Oh no, we're out of Oxygen!!!!" In this episode, "Out of Gas" we'll explore this common thread.

Like I've mentioned, it's not so much that you run out of oxygen, you get CO2 poisoning. Read below excerpt I plagiarized from another blog:

The issue of suffocating in an enclosed space is not one of running
out of oxygen; it's one of being poisoned by carbon dioxide -- CO2.
CO2 becomes toxic at a concentration of 1%. (Normal atmospheric
concentration is 0.036 percent (360 ppmv).) A concentration of 10% can
cause respiratory paralysis and death within a few minutes.

How fast the CO2 level builds depends on how fast you produce it. This
would be related to how fast you are breathing. At rest you would
exhale much less than if you were exercising.

Given that a moderately active or stressed person produces about 1.7
cubic feet of CO2 per hour and assuming a concentration of 3% CO2 is
the highest safe limit, here is an equation you can use to calculate
how long a given number of people can stay in a given space before
toxic levels of CO2 build up ---

T = Number of hours of air in a sealed room


(Volume of air inside the room in cubic feet) x (3% or 0.03)
T = ---------------------------------------------------------
(Number of people) x (one person's hourly production of CO2)

2001: Space Odyssey, Arthur Clarke

The story deals with the discovery of an artifact on Earth's Moon left behind eons ago by ancient aliens. The object is made of a polished mineral and tetrahedral in shape, and is surrounded by a spherical forcefield. The first-person narrator speculates at one point that the mysterious aliens who left this structure on the Moon may have used mechanisms belonging "to a technology that lies beyond our horizons, perhaps to the technology of para-physical forces."

For millennia (evidenced by dust buildup around its forcefield) the artifact has transmitted signals into deep space, but it ceases to transmit when the astronauts who discover it breach the forcefield. The narrator hypothesises that this "sentinel" was left on the moon as a "warning beacon" for the possible intelligent and spacefaring life that might develop on Earth.

This quotation illustrates the idea, and its ramifications:

"It was only a matter of time before we found the pyramid and forced it open. Now its signals have ceased, and those whose duty it is will be turning their minds upon Earth. Perhaps they wish to help our infant civilization. But they must be very, very old, and the old are often insanely jealous of the young."

In the movie 2001: A Space Odyssey, the operation of the sentinel is reversed. It is the energy of the sun, falling for the first time on the uncovered artifact, that triggers the signal that creatures from the Earth had taken the first step into space.

Units of distance in astronomy

How Distances are Measured in Astronomy

Dealing with the numbers involved with the distances to the stars or even with those found in the solar system can be hard going. Astronomers make their lives easier by using a number of rulers (units of distance) for the distances and although they have some strange names they can be very useful for comparing the distances to stars, other galaxies and even the planets in our solar system.
AU (astronomical units)

One AU is the distance that the average distance that the Earth orbits the Sun at. The AUis most commonly used for the distances of objects with in our solar system. Pluto, the last planet in the solar system is found at an average distance of 39.47 au from the Sun. Sedna the new body nearly as large as a planet found beyond Pluto is never nearer to the Sun than 76AU and then goes to 880AU from the Sun in its giant elliptical orbit.
Light Years

One of the most common rulers is the light year. The light year is is the distance that light travel in one year (365 1/4 days). It is most commonly used for the distances to stars and other galaxies.

The nearest star is 4.2 light years away from our sun. We are 8.3 light minutes away form the Sun. the distance to the outer most planet Pluto is about 13 light hours.

Parsec (pc)

Astronomers started measuring distances from the amount that a star moves as the Earth goes from one side of the Sun to the other. Try moving your head and you will see that the postion of everything around you changes. One parsec is derived from the smallest angle measurement of 1/3,600th of a degree or an arc second that is the angle that a star at this distance would appear to move in 6 months as the Earth journeys around the Sun. A parsec is 3.2616 light years or 30,857,000,000,000 km.. Two parsecs is 6.5532 light years or twice the distance, it is not a measure of change in angles of the stars. Due to the massive distance in the universe astronomers often use multiples of parsec commonly found are kiloparsec (kpc) a 1000 parsecs or a megaparsec (Mpc) 1,000,000 parsecs.

Elecromagnetic Radiation: Milky way alternative views

How we see the milky way (in a really dark place, like camping in Eastern Oregon)



The electromagnetic spectrum:
Radio: Micro: Infra: VISIBLE LIGHT (ROYGBIV): UltraViolet (UV): X-Ray: Gamma
Radio waves have the biggest wavelength and the lowest frequency
Gamma waves have the lowest wavelength and the highest frequency

Milky way gamma ray perspective:


Milky way infra red perspective:

Hubble's Law

Hubble's law
Hubble made this discovery from his detailed measurements of the spectra produced by the light from other galaxies. Vesto Slipher had previously discovered that the dark lines in these spectra, although clearly identifiable as indicating particular elements, were slightly out of position, usually shifted towards the red
end of the spectrum {figure 5.1). Slipher explained these red-shifts in terms of the Doppler Effect: the increase in the wavelength of the spectral lines meant that our own galaxy and other galaxies were moving away from each other.
Furthermore, the bigger a galaxy's red-shift, the greater its speed of recession, i.e. the faster a galaxy and the Earth are moving apart. In fact, for speeds of recession which are small compared to the speed of light, the fractional change in the wavelength
See more information on calculations here

What we're doing in class, the calculation of Hubble's Law

Examples of Projects

Hi all,
I just want to let you hear some of the really great examples of some of the folks in our class:

Projects People are Doing:
Making a Black Hole Game of Life
Painting an abstract sort of big Bang with a coke can in the middle
Presentation on Fibonacci sequence
The golden ratio
Jewelry making
and lots lots more.


The topics to incorporate into such a project are the topics of our class:

Black Holes (worm holes, parallel universe theories, string theory)
Math (Drake’s Equation, Hubble’s Constant, Bode’s Law, etc)
Galaxy Canibalism (Colliding Galaxies)
Extra Terrestrials, habitable planets (Drake’s Equation, natural resources needed for life, biome evolution)
Astronomy in the media, myths of how science works in film

Galaxy Types

Know Galaxy Types