Hello everyone, I’m Darrell Heath with UA Little Rock’s College of Arts, Letters, and Sciences.
A good meteor shower is always worth getting excited about.
A good meteor shower is always worth getting excited about but, for many people, all they
have to show for their observing efforts are some mosquito bites and a bit of crankiness
due to lack of sleep.
There’s a bit of an art to observing meteor showers and I’m going to share with you
some tips on how to get the most out of them.
Before we go any further however, let’s do a quick review.
Meteors are the streaks of light that you can see on just about any given night throughout
the year and are caused by tiny grains of dust burning up in the Earth’s atmosphere.
These occasional meteor sightings are known as “sporadics”. Most of this dust has
its origins with comets that pass through the inner solar system and which get heated
up by the sun. As they warm up, their ices vaporize, and they leave in their wake, long
streams of dust particles. Whenever the Earth’s orbit intersects one of these dust streams,
we get to see a meteor shower.
Just as any hunter can tell you, knowing about the habits of your quarry can help determine
how successful you are in the field. The same applies to meteor showers. No two are exactly
the same, they differ in a number of fundamental details. So, find a good, useful source of
Here are a few of the more pertinent details you need to focus on for any given meteor shower.
Meteor Society are good places to start. You can also pick up magazines like Sky & Telescope
or Astronomy Magazine to learn about the month’s best offerings.
Here are a few of the more pertinent details you need to focus on for any given meteor shower.
1) Know the peak nights and the peak times. It’s a common misconception that a meteor
shower happens on a single night of the year, in reality, they are often spread out over
a sudden peak in numbers followed by a slow decline as the Earth exits the stream.
How long the peak lasts varies from one shower to the next. January’s Quadrantid Meteor
background rates, then, as the Earth approaches the meteor stream, there’s a steady uptick
in shower numbers. As the Earth travels through the densest portions of the stream there is
a sudden peak in numbers followed by a slow decline as the Earth exits the stream. How
long the peak lasts varies from one shower to the next. January’s Quadrantid Meteor
Shower has a peak that last for only a few hours while November’s Southern Taurid Meteor
Shower has a broad maximum spread out over several days. Be aware that the predicted
peak dates and times may not always favor the area on the globe you happen to be living
in during any given meteor shower. Some years, for some showers, it might be the folks in
eastern Europe or Asia who are supposed to see the most meteors, while those of us here
in North America are, well, left in the dark. Other times, we get the best views and it’s
the folks on the other side of the globe who are seeing diddly. Now, in some of your sources,
you might see the peak times listed in Coordinated Universal Time (or, UTC), this is the time
standard used around the world and is the basis or our Civil Time. UTC does not acknowledge
time zones, but because we all live in them, you are going to have to do a little bit of
math in order to translate it. For those of us in Central Daylight Time, subtract 5 hours
from the given UTC, if it’s Central Standard Time, subtract 6 hours from the listed UTC.
For all others, you might want to consult the internet to translate UTC into your time zone.
2) Know the zenithal hourly rate and then be prepared to adjust your expectations.
Every meteor shower has its own zenithal hourly rate, all this means is that it’s the potential
number of meteors you could see per hour, during peak times, given perfect viewing conditions.
Sounds simple doesn’t it? Your source says that you can see 120 meteors per hour on a
certain night, you get all excited about seeing this amazing spectacle and when the time comes
you may only see half that. What happened? Did you get the time and date wrong? Did the
source lie? What’s likely happened is the result of a frequently misunderstood bit of
meteor shower vocabulary. What people always get wrong about the zenithal hourly rate are
that those numbers are all idealized. These are the numbers you could potentially see
given that you had absolutely perfect observing conditions. Unfortunately, having those perfect
conditions are extraordinarily rare and there are a lot of different variables that are
going to undermine your chances of seeing any meteors at all. Some of these variables
you can control, others you won’t. For example, how dark is your sky? It’s a sad reality
of stargazing that the insidious effects of light pollution have conspired to not only
steal the stars from the sky, but your chances of seeing meteors as well. Because most meteors
are rather faint, you will need to find yourself an observing location away from city lights
and that offers you the darkest skies possible. A quick way to assess the quality of your
local sky is to find the Little Dipper in the constellation of Ursa Minor, the Little Bear.
The seven stars making up the Little Dipper range in brightness from Polaris, the
brightest of them, shining at an apparent magnitude of 2, to Alasco, a star making up
one of the corners of the dipper’s cup, feebly shining with an apparent magnitude of 5,
putting it close to the threshold of naked eye visibility. If you can see all seven
of the Little Dipper’s stars then congratulations, you have very dark skies and your chance of
seeing lots of meteors is pretty good. If all you can see is Polaris, then you need
to get busy finding a better site. There are more accurate scales available for evaluating
just how dark your sky is and, thankfully, you don’t have to do the work, others have
done it for you. All you need to do is go online and search for dark sky maps that can
help you find the nearest dark sky to your location. A good place to begin is the website
for the International Dark-Sky Association.
If you live here in Arkansas, you are in better luck, because we have the
Arkansas Natural Sky Association, a state chapter of the International Dark-Sky Association.
At their web site, you will not only find dark sky maps for locations around the state,
you will also find suggested parks to visit for all your stargazing needs.
3) And while we are on the subject of light pollution, keep in mind that there is a natural
source for it hanging over our heads for a good part of each month, the moon. During
new, crescent, and quarter phases, the moon may not be an issue, but when it is more than
half full, the moon’s silvery glow will be a problem, so you will have to check and
see what phase the moon is in during the peak times of your favorite meteor shower. If it
happens to be in a troublesome phase, don’t entirely despair because you can mitigate
its effects by working around it. Simply try and find a location that has mountains, tree
lines, or even buildings that might block it from view during a shower’s peak hours.
This strategy won’t completely solve the problem, but it might help you see just a
few more meteors than you would otherwise.
4) Aside from selecting an observing site with dark skies, you also want to make sure
that your location affords you as big a view of the sky as possible. A mountain or hill
top for example is going to give you more sky in which to see meteors than would a field
at a lower elevation surrounded by trees.
5) Know the radiant. If you were to trace back all the meteors you see during a meteor
shower’s peak, you will notice that the majority of them seem to converge upon one
section of the sky, usually from within the borders of a constellation. This point upon
the sky is called the radiant and most meteor showers derive their name either from that
of the constellation the radiant is located in, or from a star within the constellation.
But here’s what you need to know: the time at which the radiant will be at its highest
in the sky. Typically, on a peak night, the radiant begins the evening by being low in
the sky, but as the hours pass, it gains altitude as it moves in a westerly direction across
the sky, finally culminating at its highest point upon the sky before it eventually sets
in the west.
If you do happen to know where the radiant is upon the sky,
don’t focus all of your attention in that direction because meteors can be seen in any
part of the sky during a shower. And if you’ve ever wondered why the peak times for most
meteor showers occur during the wee hours of the morning, it’s because that is often
the time that the radiant is at its highest point.
Okay, let me impart to you just a few more tips before I go:
Once again, I stress that you dial back your expectations. It may be called a meteor
shower, but that doesn’t mean that they are going to fall from the sky like rain.
If you have near perfect conditions, and you have a very productive shower like August’s
Perseids or December’s Geminids, then you might see a meteor every minute or two during
the peak hours. Or, you might not see any. You might stay up for hours and only
have a few mosquito bites to show for it, but then again, you
might get lucky by being in the right place and the right time and see the show of a lifetime.
But, if you stay indoors, you won’t see any.
Be patient. Sometimes there will be moments when the shower is active and then there will
be lulls. That’s just the way it is, accept it. Carry along some music to keep yourself
entertained during the wait. Let your eyes get dark adapted. This a
process that can take up to an hour to complete. Once your night vision is in perfect working
order, you will see more meteors. BUT, if you look at your cell phone, laptop, or any
other kind of white light, even for a second, then your night vision is ruined, and you
will need to wait another hour for the process to complete itself again. To avoid this, use
a red filtered flashlight. The longer wavelength of red light is less destructive to your night
vision. If you don’t have a red flashlight, just tape some red plastic film over a flashlight
you have around the house. You can buy red plastic film that is used to repair broken taillights.
Get comfortable with a blanket or sleeping
bag on the ground or use a reclining lawn chair. The main thing you want to avoid is
straining your neck. Expect to see meteors anywhere on the sky, don’t focus your attention
solely on where the radiant is located. Have lots of water and snacks on hand.
Something with caffeine in it will be your best friend come 2:00 AM
It can get chilly during the wee hours, especially if you are observing from a higher
altitude. Be prepared for it. Pack the bug spray, because nothing can
ruin a good night out under the stars more quickly than can a swarm of blood sucking insects.
Invite friends and family to join you,
make it a party. Even if you don’t see many meteors, you can have spent quality time
with people you love.
Also meteor showers can be inexpensive
and romantic date nights.
Okay, that’s it for now, I hope that you find this information useful the next time you
observe a meteor shower and you are outside looking up in both awe and wonder.