"ASK UNCLE SOL" is a (fairly) regular feature, written by Sheldon Cohen, in the Smoky Mountain Astronomical Society Bulletin. Other clubs are welcome to reprint it in their newsletters, but we'd appreciate an acknowledgement. This month's question comes from little Debbie Draco of Dayton, TN. Debbie asks, "Uncle Sol, what's the difference between amateur astronomers and professional astronomers?" Uncle Sol answers: Debbie, the "amateur" in "amateur astronomer" comes from the Latin amare, to love: an amateur is a lover. Of course, no real lover would pack up 200 lbs. of gear and head for the countryside as night falls. The usage for stargazers arose in seventeenth century Italy, when the use of the telescope spread and many people (almost all of them men) started spending their nights outdoors with the stars. Their wives, annoyed at being left alone, took young gentlemen (amorosi) to comfort them. (Many of these amorosi were professionals.) The term was soon applied ironically to the betrayed husbands. When, in the Eighteenth Century, France beat Italy, 7-3, in the semi-finals, the astronomy championship passed into gallic hands, and amateur displaced amoroso. Because their work was so demanding and required keeping odd hours, the professional amorosi were usually tired: professional comes from the Latin roots pro, meaning like and fessus, meaning tired - a professional is like tired. For today's astronomers that's because these dudes spend all day wracking their brains with numbers and math and stuff like that. When the sun goes down they are so shot they flop into bed and are immediately asleep - they're no lovers either. Since they sleep all night, many of them have little idea of what a star looks like in real life. The younger generation thinks galaxies look like CCD images, and are disappointed when little boxes don't show up through a telescope. --from our 90/03 issue. This month's question comes from little Debbie Dempster of Dumpster, TN. Debbie asks, "Uncle Sol, why are the optics for most of our cameras and eyepieces made in Japan?" Uncle Sol answers: It took me a little research to figure this one out Debbie, but I finally discovered the answer. You probably have seen those late-night TV commercials advertising audio tapes with subliminal messages on them: "I really like you," "You're not hungry," "You can be rich!" and "Order more tapes!" Well, the function of a lens is to direct photons to their assigned places, so the more you know about photons the better off you are. Here the Japanese have a tremendous advantage. It seems that their apartments are too cramped for real beds, so they sleep on photons! The subliminal benefit this provides undoubtedly gives them their edge. --90/04 This month's question was sent in by Lance Reventlow, of Morristown, TN. Lance writes: "Dear Uncle Sol, I read in last month's SMAS bulletin that an 8" f/8 scope used with a 26mm eyepiece is equivalent to an 8" f/4 scope used with a 13mm eyepiece. This is definitely not true! "I frequently take my 8" f/4 out into the countryside for star parties, using a 13mm eyepiece. But even with a 26mm eyepiece, my 8" f/8 won't fit in the car!" Uncle Sol answers: Lance, you have made a common beginner's mistake. The two scopes, with those eyepieces, are equivalent outside the car. But when you try to put the f/8 inside your car, your automobile's own optics come into play. Until you adjust them, your car cannot benefit from the new eyepiece. If you are unfamiliar with automotive optics, you must first learn to identify the car's primary or objective lens (so called because while you are driving, you can see your objective in it). Sit in the driver's seat and look 30 degrees to your right and 30 degrees up. You will notice a small mirror, known as the secondary. If your car is a Schmidt Cassegrain, the secondary is attached to the primary lens; if your car is a Newtonian, the secondary is attached to the primary holder, just above the primary. Now that you've located your car's primary lens, you must adjust the car's focal length to match the change in the telescope. Since auto primaries are zero magnification (technically, they are corrector plates) this is a simple task. If your car is one of the newer models equipped with an adjustable primary holder, move the primary forward to double the distance between the primary and the ocular lens, located behind the rear seat, at the back end of the car's optical train. If you have an older, non-adjustable model, tap with a 16 oz ball pein hammer on the primary until it has deformed into a concave hemisphere, or even better, popped out. Your f/8 now fits in the car! But before you drive off, you must collimate the car's optics. Climb onto the trunk and, with your head on the car's central axis, look through the ocular lens into the secondary. Have a friend adjust the secondary until the image of your face is centered in it. (Hint: this will be easier if you've painted a black dot on your nose.) Once your face is centered in the secondary, have your friend adjust the position of the 8" on the rear seat (the seat nearest the car's ocular lens) until it occults the black dot. If you cannot do this, your nose is not aligned with your visual axis. Tap your nose with an occulting bar while you twirl around in right ascension. If you hit your nose hard enough, you will see stars. When you are aligned these stars will describe concentric circles: "Oh, there's a pretty blue circle with a 7" radius, but it's not half as pretty as that red one with an 8" radius. Say, they both have the same center!" If you find these adjustments difficult, you may want to invest in an auto collimating eyepiece. --90/05 This month's question was sent in by little Debbie Doubting, a fifth-grader in Daytown, TN. Debbie asks, "Uncle Sol, What is Universal Time?" Uncle Sol answers: Debbie, that's a very easy question to answer. But first you have to understand solar time, the mean solar day, the sidereal day, the synodic month, the tropical month, radioactive half-life, nautical twilight, time zones, the International Date Line, ascending and descending nodes, the calendar month, Ephemeris Time, the lunar month, the Julian Date, the equinox and solstice, tidal friction and plate techtonics, Greenwich Mean Time (GMT), argument of eccentricity, Standard Time (ST), Daylight Savings Time (DST), Local Mean Time (LMT), Civil Time (CT), and International Atomic Time (TAI). Since its TGB (time to go to bed), I can't explain all of this. I'll stick to the basics. First, calendar time is measured by calendars, and calendars are never wrong: if the calendar says it's June 4th, it is June 4th. But this accuracy is only good for a year. Trying to save money by using last year's calendar is false economy, since the warranty on these precision timepieces lasts only through December. Rulers measures space, not time, and since they are made of wood or metal instead of paper, they are good year after year. Clocks, like calendars, measure time, but since clocks have working parts, clocks can be wrong. But like rulers, they can be used year after year. Most rulers measure only a little space, whereas a clock measures all the time there is in the universe - at that time.* So time is universal - if it's 3 o'clock EDT in Knoxville, it is 3 o'clock EDT in Knoxville all over the universe, whereas if it's 2 miles to the 7-11, from someplace else it might be 3 miles, or even more. Before this was discovered it was thought that it might be noon here, and a completely different time on the sun - say a quarter to eight, or even half past ten! Second, the earth revolves around the sun, and rotates on its axis at the same time. Something can rotate while remaining in the same place, but since the earth rotates and revolves around the sun at the same time (just as you can chew gum and walk at the same time), by the time it's back where it used to be, its gone - unlike your gum. This is why the moon is never on time. To verify this, time its rise one day, and then check it the next. You'll find it's not on time. (This isn't really the moon's fault - the moon shows up on time, but by then the earth is gone.) Since the earth is gone, it's not there. Of course, it used to be there, but it isn't anymore. It's someplace else. And the time it would have been had it been there is gone as well - it too is someplace else. That someplace else is Greenwich, England. (All things, once past their time, go to England.) Consequently, every day (i.e., all the time) old time flows back to Greenwich, for time, too, used to be someplace else. To verify this, drop a steak on the ground, and note when the sun first strikes it. Soon thereafter, the sun will cease having first struck it. As soon as this happens make a note of the time, and think about this for an hour. When the sun first struck the steak, it was (for the purposes of illustration) 3 o'clock. Now the sun has moved on, and where is 3 o'clock? In Nashville, of course, but it's also back in Greenwich. This doesn't mean it's 3 o'clock in Greenwich - it's 3 o'clock in Nashville. But Nashville doesn't have 3 o'clock. There's an important difference between its' being 3 in Greenwich, and 3's being in Greenwich. At this point 3 is in Greenwich, but since Greenwich is, during Standard Time, 5 hours ahead of us, it's 8 o'clock there. OK, so far? It's 8 o'clock in Greenwich, but Greenwich has 3 o'clock. The extra five hours are stored in the Bank of England, to be recycled as needed. On average each hour is needed every 60 minutes (to make the shows on TV change). But the Bank of England knows that the earth's orbit is inclined, and the Bank of England is inclined, so it releases these hours in accordance with a formula known as "the equation of time," keeping the difference as profit. To further increase profits, the bank stores twenty-three of the twenty-four hours in England. The time we know is the single remaining hour, released at Greenwich every midnight to race around the world. This is why an hour from now in Nashville it is literally the same hour it is here now. And it explains why the English are slow - they know they have a lot of time - and why MPs always proudly shout, "Here, here" - meaning, "Here [in England] we have the time." To verify this, go to England and ask someone, "Do you have the time?" Nowadays, Greenwich Time is called "Universal Time." This is because when our astronauts landed on the moon they looked at their watches and verified that it was the same time there that it is on earth. So we now know that some of our time is leaking out, causing it to be the same time all over the universe! Astronomers still don't know what physical mechanism powers this strange phenomenon, but they believe this is why we sometimes don't have enough time. [S&T has a simplified and somewhat dated (April '89) explanation of UT, but they gloss over many of the details.] * My apologies for stealing this line, which I think comes from an old Second City routine. --90/06