Category: Science

Estimates vary. A lot. Space.com reports that the range accepted by many astronomers is 100-200 billion (bit.ly/galaxies-billions). As if that weren’t a pretty wide range already, phys.org reports that a group of European researchers recently found that we’d missed a few, and the number could be more like 2 trillion. (bit.ly/galaxies-trillions). Incidentally, the team that found 2 trillion was begun by an undergraduate student (Aaron Wilkinson) who is now close to done with his Ph.D. on this very topic.

Yes, but so far only in one direction: forward, and at the same speed everyone else is traveling. Theoretically, you could travel briefly slower than everyone by approaching the speed of light. When you return, everyone else will be old already, and that’s no fun. Kip Thorne at Cal Tech has studied this question. I’m not a theoretical physicist or a Nobel Laureate, so I’m just going to have to trust him when he says, “nope”: bit.ly/kip-time

You can squish bacteria, but it’s not easy. Bacteria are tiny (about 2 micrometers long, or 2×10−6 meters), which means if you stepped on one even on a smooth floor, the microgrooves in the floor would be plenty big to protect them. If scientists aren’t careful, they do squish them with microscope slide glass or by stirring too long & vigorously with a glass rod in a petri dish. Sturdy little guys, though: they populate the bottom of the Marianas Trench at pressures that would crush us instantly: bit.ly/bacteria-marianas. I don’t know if they make a sound when they fall, but bacteria apparently do make noises: bit.ly/bacteria-sounds.

Yes. The folks at the New England Aquarium have a blog posting answering this very question (complete with images of penguin knees) at bit.ly/penguin-knees. (Did you know we have lots of books about penguins? Do a subject search for penguins to find them!)

Environmentally, the mechanical pencil is the better option as it has the potential to last for a very long time: you use up the lead in a wooden pencil and you need to get another pencil; you use up the lead in a mechanical pencil and you simply refill it.

No. While initial rotation of Venus during primordial times was probably fast and prograde, Venus has been in its present configuration of slow retrograde motion within the age of the Solar System, possibly during the first billion years (Correia, 2003; bit.ly/spinofvenus). It is believed that the present motion of Venus is a steady state between gravitational tides and thermally driven atmospheric tides, as well as tidal dissipation effects due to proximity to the Sun (Correia, 2010; bit.ly/tidalevol).

Hm…. Did you mean “in” Newton? My Newton area colleagues haven’t noticed a flower-wilting phenomenon there.  In most years, spring flowers follow a succession – early bulbs (crocus & snowdrops), then the yellow explosions of forsythia, then later bulbs (daffodils and other narcissus), then fruit trees like apples and cherries. This year, the late spring meant everything bloomed all at once. It was a feast for the eyes (and a trial for some noses) and all subsided all at once. If there’s a problem specific to Newton Street in Brighton, IDK.

Among climate scientists there is a consensus that raising the temperature will increase both the severity and frequency of extreme weather events. It’s a matter of physics: increased energy adds more air circulation and water vapor to the climate, both of which fuel weather events. It’s very hard to say, however, that any particular storm is “caused” by global warming. For an introductory answer to this question, see Storm Surge: Hurricane Sandy, Our Changing Climate, and Extreme Weather of the Past and Future, by Adam Sobel (MIT meteorology PhD): O’Neill Library QC945 .S624 2014.)