The Arietid Meteor Shower

.....Rather unfortunately, tomorrow morning the Arietid meteor shower will be at its peak. Wow! I'm only one sentence in and I already have to explain at least four things ...

.....Meteors, or shooting stars, are small (hopefully!) particles that hit the Earth's atmosphere. Since the Earth is moving through space at about thirty kilometers every second, and the particle is going to be moving bout the same speed, the friction of the air will heat the object to glowing hot as it dissolves. Those flashing lights can come from several sources. Some of them are the flotsam and jetsam of the solar system, little pieces of leftover rock that have been floating around from the beginning of the solar system. Some have actually been blasted off of other planetary bodies, like the Moon, Mars, or asteroids - even asteroids that have been shattered in impacts in the distant past of the solar system. This is compelling stuff, but it is unfortunately not what we are talking about here. Some of these meteors can be seen each night, usually on the order of a half-dozen or so, if you're lucky. (Source)

....Meteors can also be heat tiles, nuts, bolts, tool bags, etc. After fifty years of space travel, a rather astounding amount of space junk has built up in the space around the Earth, to the point where this junk is a positive threat to space travel and new satellites that has to constantly be taken into account. (I had lived for four years in central Florida when I had cause to remember that any object launched into orbit will adopt an orbit that carried it over its original launch point periodically. How disappointing it was to have four years of meteor watching cheapened by realizing that some large fraction of what I had seen was "just" junk!)

.....Meteors can also come from comets. Consider a bright comet, passing through the inner solar system:

.....We see a comet by looking at the bright tail. We see the bright tail because the tail is made of many particles of ice and ice-covered dust released from the comet during eruptions caused by heating from the Sun. These eruptions also release a lot of dust and rocky particles from the comet, and those bits and pieces don't simply disappear when the comet (now the comet et al), moves far enough away from the Sun for the nucleus to quiet down. (We're not allowed to have something simply appear or disappear without a way to explain where it came from or where it went.) The bits that are blasted off stay in the same orbit, although they do spread out through the orbit over time. these ex-comet parts are what give rise to meteor showers.

.....Comets rarely (dramatic understatement) impact the Earth. Even when their orbits cross the Earth's orbit, the chances of the Earth and the comet both being there at the same time are remarkably tiny. However, if the comet has passed by the Sun enough that there is a great deal of debris spread throughout the orbit, the Earth can hit this. Each of these small particles becomes a meteor, and since the meteors are all coming from the same stream, and thus approaching the Earth along the comet's orbit, all these meteors appear to be coming from the same spot in the sky. (The spot where the comet's incoming orbit hits an imaginary shell representing the sky around the Earth.) This spot in the sky is called the radiant of the meteor shower, the point that meteors in this shower appear to radiate away from, and the point for this shower is in the constellation Aries. Hence, this meteor shower is refered to as the Arietid Meteor Shower. (The map is good for 4 AM tomorrow morning.)

.....I said "unfortunately" at the beginning of this post because the above star map, showing the location of the Arietid radiant, shows the sky shortly before dawn. This means that the Arietid shower is a daytime shower, and there are darn few meteors bright enough to be seen during the day. Sure, there is a chance to see meteors in the couple of hours before dawn ...

..... The typical number of meteors per hour for the peak of the Arietid meteor shower is about fifty per hour, but that is misleading. You might (on average) see fifty meteors an hour if your sky was completely without light pollution, and the radiant was directly overhead, but we aren't going to get that. A perhaps sizeable fraction of you paused at my words "before dawn" earlier. Yep, when I suggest that something cool is going to be visible in the sky, nothing kills the joy faster than the words "before dawn". At this point, I might even have negative readers for the rest of this paragraph ...

....So if you aren't willing to get up before dawn (statistically speaking, you aren't) is there any way to detect meteors during the day? As it turns out ...

.....Meteors heat up, glow, and (mostly) dissolve in the upper atmosphere. Along their paths, they leave ionized gases, knocking electrons briefly free, and this can reflect radio waves moving through the atmosphere, causing you to briefly hear radio stations more than a thousand miles away. If tomorrow morning the radio briefly cuts out, or if some station you don't recognize surges for a few seconds, that might be due to the path of a meteor.

.....Or, if you want to try to see some of these, look to the east before dawn. One advantage of these types of meteor showers is that the meteors will move comparatively slowly. This is an advantage if you, like me, tend to be able to summon fast-moving meteors simply by looking down.