There's a light show coming to Salem (and beyond) and it involves the most exciting and elusive lights in the night sky. What are these lights? Hint: They have nothing to do with starlight, even though their nickname is associated with stars. Read on for the answer and a short guide to enjoying these flashing treasures.
Starlight dominates the night sky in the Salem area. When we look up into the night sky and see the Moon, stars, and planets, we can trace almost all the light we see back to a star -- our Sun or one of the thousands of stars we can see with the naked eye. The Moon and planets are reflecting sunlight. The same applies to the man-made satellites we can see in the night sky, like the International Space Station. If you can see a comet, almost all that light is from our star, the Sun. But for drama and excitement, it's hard to beat the light that doesn't depend on starlight. What's that mysterious light? A meteor! Or better yet, METEORS!
There's a stream of meteors headed our (Earth's) way and Salem is a great place to view them because we have dark skies nearby. On the night of Monday, November 17th, (into the morning of November 18th) the Leonid meteor shower will reach its peak. Let's translate that into normal English and figure out how to enjoy the show.
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A meteor near the Trifid Nebula. |
Let's start with terms. You might know meteors as "falling stars" or "shooting stars". But they aren't stars. And despite the coincidental timing of hunting season, there's no real shooting involved.
Meteors are glowing bits of dust and rock that have made the mistake of crashing into Earth's atmosphere. They're only glowing because they hit the Earth's outer atmosphere at amazing speeds. As the air is compressed by the particle or rock, the air heats and eventually becomes hot enough to glow. Even after the meteor has passed, the air can still glow until it cools off. That stream of hot, glowing gas is the bright streak of light you see in the sky.
What's the "shower" part? On any clear, moonless night of the year, you can watch the skies and see a few meteors. Usually the meteors are going in random directions and they don't have any relation to one another -- just isolated stuff in space that hits Earth's atmosphere to give you a spontaneous (and short) show. But during a meteor shower, you'll see more meteors and the meteors appear to come from a single point in the sky. Each meteor shower has its own "radiant" or central point in the sky. The Leonid shower has its radiant in the constellation Leo, the lion. You can easily pick out the constellation because the head of the lion looks like a backward question mark in the sky. If you want to see Leo before the shower, just go out on a clear night and look toward the east after midnight. (If you know the two "pointer stars" in the Big Dipper that point to Polaris, you can follow them backward to see the constellation Leo.)
So we know about meteors and meteor showers. But what's the best way to enjoy a shower? The most critical part is having a clear sky -- no clouds and no haze. If the sky is cloudy, the show is over. If it's hazy, you'll see only the brightest meteors. A Full Moon can ruin the show just like haze. But for the 2014 Leonid shower, the timing is great: The Moon won't rise until almost 3 AM, and even then, it'll just be a thin crescent.
If you'll be outside during a mid-November night, you'll need to be prepared for cold weather. If it's clear enough to view meteors, it'll probably be very chilly. So bundle up. Think "blankets", "thermal socks", and "gloves".
There are two wonderful things about viewing meteors: First, your eyes are the best tools for the job. You'll see more meteors with your eyes than you would with a telescope or binoculars. Try to avoid looking at a bright light because your eyes will lose some sensitivity for a while. If you need a light, a dim, red flashlight is the best. (The light should be red. The color of the flashlight isn't important.) Second, the best viewing position is horizontal. That summer lounge chair -- fully reclined -- is the perfect meteor viewing furniture. Try not to fall asleep.
Your viewing location is important. If you can get to a dark location with a low horizon, you'll have the best view. But even in downtown Salem, if you can see stars and constellations, you can see meteors. It's best if you have a good view of the eastern horizon. But you might see some of the best (and longest) meteors of the shower if you look away from the eastern sky. So the horizon view isn't as important as finding a dark location.
So where and when do you look? Most astronomers recommend viewing a meteor shower near the radiant -- in this case, the constellation Leo -- and viewing when the radiant is high in the sky (but before dawn brightens the sky). If you do that, you'll see the most meteors. And you'll also be in the cold and dark about 4 AM. If you're not ready to make that combination of sacrifices, there's good news. And it involves normal hours (or at least "more normal" hours).
It's true that 4 AM on the morning of November 18th is the time when you'll see the most meteors. But the Earth starts encountering the stream of dust and rocks for a couple of weeks before peak of the shower and we continue seeing those meteors for a couple more weeks. The numbers taper up before the peak and taper down after the peak. So on late evenings a few days before and after the 17th/18th you might catch a few bright, long meteors coming from the eastern part of the sky.
Remember I said that the "most" meteors are seen near the radiant. But many of those meteors are coming right at you. (Don't worry, most burn up and the rest will miss you.) Those "right at you" meteors are unimpressive -- just a short blip in the sky -- because you are looking down (or is it "up") the path of the meteor. The impressive meteors are the ones that miss you by a lot and streak all the way across the sky. Yes, watching the radiant will give you the MOST meteors. Looking away from the radiant, you'll see fewer, but you'll see the best meteors.
Meteor watching can be a fun family sport. Each family member can patrol a separate part of the sky. Some meteors are long enough to hear one person shout (or gasp) but still let another person turn to see part of the streak in the sky. The Leonid meteors tend to be faster than other meteors: They can hit the atmosphere at 45 miles per second. (That's a muzzle velocity of over 237,500 feet per second.)
A meteor shower -- even a good one like the Leonids near its peak -- is more "waiting" than "seeing". The predicted peak of meteor activity for the 2014 Leonid shower is about 15 meteors per hour. That's less than the peak from other years. But meteor showers often surprise astronomers. We could see more or less. It takes patience but the payoff is exciting.
Here's the summary: Find skies with low light pollution, and hopefully a good view to the eastern horizon. Dress for cold weather and relax in a reclining chair or on a blanket. The best time is 2-5 AM on the November 18th. The second best time is anytime during any night until the 30th. The only tools you need are your eyes (and your patience).
There's a lot more interesting information about meteors. See the Salem Skies blog post titled "
Meteors". You can also find links to other meteor websites there. And you can leave suggestions, questions, and meteor viewing reports in the Comments section.
Enjoy the lion's light show! Clear skies.
EPILOGUE: The cool weather — into single digits — took some of the fun out of viewing the Leonids. A short viewing session at 10 PM on the 17th showed about 6 meteors from the shower. A much brighter meteor (not a Leonid) went in the opposite direction of the Leonids. Later, at 4 AM on the 18th, I saw 10 more meteors over 45 minutes.