1. Code: that is, computer programs written in a programming language ('code'). In this case, the programs were for processing and analyzing astronomical images.
2. T.O.: Telescope Operator. All large astronomical telescopes are controlled by telescope operators, rather than astronomers. In this line, I am not criticizing the T.O., only emphasizing that the weather was so hopeless he had nothing better to do than play video games. I have great respect for T.O's. Each one is an expert on his or her specific telescope, and can operate it more effectively than an astronomer, who focuses instead on understanding the science of stars, galaxies, etc. The astronomer tells the T.O. what he or she wants the telescope to do, and the T.O. makes the telescope do it, unless it can't without risk of damage. This scenario happens frequently: one of the main purposes of a T.O. is to protect the telescope from over-eager astronomers asking it to do the impossible (like observe while it's snowing, for example).
3. run: Astronomers typically talk about telescope time in terms of observing runs. A run is a set of contiguous nights alotted to a given astronomer, or research project. This poem was written at the end of run in which I got no good data at all: I could not try again the next night, because it was another astronomer's run.
4. charge: Modern astronomical cameras (and your digital camera at home) record images as patterns of electrical charge, often on a silicon chip. The charge is read off and encoded as an image file on a computer.
5. air: The mirror of a large telescope like the MMT must be kept at the same temperature as the surrounding air. Otherwise, eddies of different-temperature air billowing off the mirror blur the images. Because a 6.5 meter diameter disk of glass doesn't warm up or cool down easily, air is always being blasted at high speed through the hollow, honeycomb structure of the mirror, forcing the glass to equilibrate quickly to any changes in the air temperature.
6. force: Among other things, this refers to the magnetic force actuators that are used to finely control the shape of the MMT's adaptive secondary mirror hundreds of times each second. This cancels out much of the blurring from Earth's turbulent atmosphere, allowing the MMT to give sharper images than the Hubble Space Telescope (though Hubble retains other advantages, such as ability to use wavelengths the MMT can't). The process of rapidly deforming a telescope mirror to sharpen images is called Adaptive Optics (AO), and is used at many telescopes. The MMT's magnetically actuated deformable secondary mirror, however, is still unique as of 2009. The poem was written in December 2005.