Stealth and Fructose, Or, Modern Science

[chris_gerrib]

Two random thoughts, related only by being results of modern science and of interest to me.

First, various folks, including my friend jeff_duntemann have argued that high-fructose corn syrup, used in place of sugar in thousands of processed foods, is the cause of America's obesity epidemic. Basically, the argument is that we metabolize fructose differently than sucrose (table sugar). It turns out that a new study from Princeton University supports this theory.

Apparently rats fed fructose, even under some calorie restrictions, will put on more weight than sucrose-fed rats at a higher calorie level. Since I've stated in the past that I wasn't convinced of the "fructose theory," it looks like I'll have to change my opinion.

Second, the question of whether or not you can have a stealthy ship is space is always of interest to science fiction writers. After all, if the Martian Space Fleet can sit in Martian orbit and watch the Terran Space Fleet leave Earth orbit, surprise attacks become difficult. The fascinating site Project Rho argues that this is the case. (Warning - space geeks can easily loose an afternoon at the Project Rho site - visit at your own risk!)

Not so fast, says the guy behind the blog Built on Facts. First, he points out that interior heat is not the same as hull temperature. It's actually a measure of energy output needed to hold a given temperature inside - just like the exterior of your oven isn't as hot as the inside. Second, this energy is broadcast, so hull shape and size matters.

At any rate, he ran the numbers. For a ship with an energy output of 10,000 watts and searching for it with a 24 inch telescope, he came up with a detectability range of 5.9 million kilometers. This is still a goodly distance - 15 times the distance from the Earth to the Moon - but only 10% of the distance to Mars at opposition - the closest point on our orbits.

Comments

[jordan179.livejournal.com]

Also note the assumption that the IR is broadcast. That would be true if the hull was designed and the ship operated with no view toward stealth, but if the hull were designed and the ship operated with stealth as a consideration, one could emit heat preferentially away from the sensors from which one was trying to avoid detection. This would be possible even today through materials selection and where one aimed the drive; it will be more possible in the future, when the technology of metamaterials has matured a bit.

Ah, random science geek stuff

[dalecoz.livejournal.com]

Interesting. I've been trying to get high fructose corn syrup out of my diet. My stealth space fleet detector is still in stealth mode.