Q) Does anybody keep vampire bats as pets?
Hit or Myth?
A reader asks if it's true that the interstate highway system was designed so that one in every five miles is straight enough to be a runway in times of war or emergency.
Fortunately for you nervous drivers, no. This urban legend seems to date from the early 1940s, when the Army Air Force and the Public Roads Administration, with war on the horizon, started building airstrips adjacent to public highways. Only 26 were completed, and the Eisenhower Interstate System of 1956 included nothing about airstrips or any one-in-five rule.
Of course, that doesn't stop dozens of pilots a year from using the interstates as their own personal landing strips. This past May, a traffic plane from a San Francisco news channel ran out of fuel and had to plunk down on the East Bay F...
Illustration by Jason Holley
Susan Sanford, Cottonwood, Arizona
A) If they do, they're breaking the law. Keeping these egg-size mammalsthe common vampire bat, Desmodus rotundus, and two other, rarer speciesas pets is prohibited in the U.S. For one thing, they can give you rabies, but a major concern is the economic damage they cause by preying on livestock, like they do in their native Central and South America. Daniel Abram, founder of the New Mexico Bat Research Institute, says that probably doesn't stop a small black market from dabbling in them. But as we know from zoos and universities licensed to care for the creatures, they don't exactly make cuddly companions. For starters, they need fresh blood every day or they'll die. This means their owners either need to live near a slaughterhouse that will supply them with blood, or must own some goats or chickens that the little guys can sink their teeth into every night. Granted, they're cuteif you like the miniature flying Nosferatu lookbut wouldn't you be happier with a kitten?
Q) Can any telescope see the U.S. flag on the moon?
Bruce Halliday, Shrewsbury, Massachusetts
A) To spot the flag planted by Neil Armstrong and Buzz Aldrinor any of the other five flags Americans left on the moon between 1969 and 1972you'd need perfect observing conditions and a telescope with an aperture as big as five football fields. But before you call Very Large Telescopes R' Us, be aware that perfect conditions can't exist on Earth. Even on the clearest night, from the highest peak, says Boston University astronomer Amanda Bosh, no scope could possibly see through our planet's gauzy, shifting atmosphere and spy those three-by-five-foot banners. And that's assuming they're still there. Don't tell Francis Scott Key, but given that the moon's weak atmosphere can't block micro-meteorites and UV rays, the flags may have disintegrated long ago.
Q) When cyclists draft each other, does the drafting cause drag on the leader?
Ed Reiff, Skokie, Illinois
A) Actually, everybody benefits from draftingthe lead rider just benefits less. It's well known that the leader, by cutting wind resistance, makes life smoother for the rest of the packat race speeds, 17 percent easier for the second rider, 38 percent for the next, and 40 percent for the fourth position on back. But the guy fronting the pace line doesn't do more work than he would if cycling by himself; in fact, he uses 3 percent less energy. According to Chester Kyle, a Long Beach, Californiabased aerodynamicist who's designed ultrasleek clothes for Lance Armstrong, a cyclist riding solo creates several drag-inducing vortices around him, as well as low-pressure cavities that suck him backwards. If there's a rider clinging to his back wheel, those anomalies in the slipstream straighten out. The same goes for freeway driving: Tailgaters, oddly enough, save you gas.