The first meteor shower of 2013 is the annual Quadrantid meteor shower. The Quadrantids are a reliable shower, producing 60-120 ZHR, one to two meteors per minute. The Quadrantids are named for the obsolete constellation Quadrans Muralis, now part of the constellation Boötes.
Unlike other showers where activity can occur for days or even weeks, the Quadrantids have a sharp peak, activity falls off rapidly on the preceding and following nights, or even a few hours away from the peak. Thus it is important to observe the Quadrantids quite near the peak prediction. For 2013 the peak is predicted for January 3rd around 13:33UT, or 03:33HST on this side of the globe, excellent timing. This is the good news for observers here in Hawai’i. The bad news is that the peak will be sullied by the light of a bright last quarter Moon.
The Perseids are one of the most watched meteor showers. Occurring during northern hemisphere summer, the shower can be appreciated on a summer night. Quite a difference from the other reliable showers such as the Leonids and Quadrantids, that occur in November and January. Consider a warm summer evening under a dark sky full of stars, a picnic blanket, relaxing while shooting stars streak across the sky. What could be better?
The Perseid meteor shower occurs when the Earth passes through a stream of debris along the orbit of Comet Swift-Tuttle. This shower has been consistent throughout recorded history, mentioned in Chinese, Japanese and Korean records as early as the 1st century. Active from July 17th to August 24th, the shower will build slowly for weeks before the peak. A week before or after peak the shower can still be seen with around 20 meteors each hour. The shower is a northern hemisphere event, for southern observers the radiant never rises above the horizon.
For meteor watchers there is probably no more anticipated show that the annual Leonid Meteor Shower. The Leonids are renowned for reliable showings featuring bright fireballs.
The reputation is not without reason, Leonid events over the last decades have produced spectacular showers. The 2001 Leonids have become legendary, for a few brief hours on the morning of November 17th the shower became a true meteor storm, with rates of more than one thousand meteors an hour visible across the western United States and the Pacific. The sky was constantly peppered with streaks, many dim, but some very bright, every few minutes a fireball would be brilliant enough to light up the landscape. Other observers will mention that the 1998 Leonids produced a impressive number of bright fireballs, making that year particularly memorable.
Nor is the 2001 event unprecedented. This has happened in the past, with Leonid meteor storms occurring several times in the last couple centuries. In 1833 a massive shower woke residents across the eastern United States with a fury that had many thinking that Judgment Day was upon them.
The Leonid meteor storms incited terror and religious revelation, but also stimulated the study of meteor science. It is from studies of these storms that astronomers began to realize that meteor showers were natural, and predicatable phenomena. This led to the realization that the annual meteor showers were associated with comets with orbits that cross the orbit of the Earth.
Just how impressive a show depends on a set of complex factors, meteor prediction is not an exact science, but astronomers are getting steadily better at these predictions. The meteoroids are found in clouds of debris left behind by a comet. In the case of the Leonids this is comet Temple-Tuttle, which has an orbital period of 33 years. All along the orbit of the comet there is a cloud of debris, small bits of dust and sand sized grains of rock-like material. Prediction is a matter of figuring out how this material will move about under the influences of gravity from the various planets and other factors like the pressure of the solar wind and even sunlight.
Unfortunately for meteor watchers, the 2011 Leonid shower is expected to be fairly weak, with ZHR rates around 20. There are some predicted peaks, due to specific regions of debris left behind by the comet several centuries ago, but the average meteor size is predicted to be quite small, leading to to faint meteors. This is further complicated by a bright waning gibbous Moon present during the shower peak. This is probably not a good year for Leonid observing.
Pu’u dot the landscape of the Island of Hawai’i. Pu’u, (pronounced poo-oo) is an interesting Hawaiian word that can mean hill, bump, pimple, wart, or any similar concept, but in this case generally means cinder cone. These reminders of the volcanic origins dot the sides of the big volcanoes like pimples on the face of the island. They are everywhere and each has a traditional name. Locals have used them since the dawn of civilization on the islands to give directions, describe legal land boundaries and name roads throughout the island.
Learning your way around the island is often learning the names of the Pu’u. I use them to mark my progress along my morning commute to work and note the weather above Wiamea. A large pu’u stands above the end of Saddle Road where it turns into the center of the island and another pu’u marks the intersection of Saddle Road and the Mauna Kea access road that climbs to the summit winding through the pu’u that cover the flanks of the mountian. Keck Observatory itself sits on the rim of Pu’u Hou ‘Oki.
The West Hawaii Astronomy Club’s dark sky observing site sits directly beside a small pu’u that goes by the name of Pu’u Kuainiho in a unit of State DLNR land named for Pu’u Anahulu. Nothing fancy, a large gravel lot just off a major state highway, but far anough off to avoid the headlights. Easy to find along the road from Waimea to Kona. It sits at about 2,000ft elevation, high enough to be above most of the low altitude tropical haze. Being in the rain shadow of a 14,000ft peak the site offers surprisingly reliable weather, it is often cloudy in the evening but almost always clears after dark. The only real issue is the often heavy formation of dew and some ground mists that will plague observers. The site is a comprimise between fairly decent skies offered by lower elevations here in Hawaii and the truly spectacular observing that can be had from sites high on the side of Mauna Kea at 9,000ft. The only issue is that those perfect Mauna Kea skies are accessed by a rough hour long drive up Saddle Road and are often windy and quite cold. Sometimes a warm site 15min from home on a good road wins the toss.
This time the target was meteors, a shower I had often not observed because it generally occured in the middle of Tucson’s rainy monsoon season. But a dark sky with no Moon and access to a decent dark site a few minutes away was simply too attractive. Except, of course, for the 2am setting in the alarm clock. I had expected a few other observers to be out for the peak, but when I got to the site I was alone. No matter, nothing new for me. I had brought along the Losmandy mount and the DSLR for a little attempted meteor photography and a lounge chair for relaxed meteor observing.
Set the mount up, a quick polar alignment with a polar scope good enough for wide field photography, bolt the camera on and let it go. Just lie back in the chair with a couple blankets and I am set!
OK, start the show now…
…I must have waited five minutes for the first meteor.
But meteors did appear. A few dim ones widely scattered and a few bright ones from time to time to annouce that something out of the ordinary was going on. I kept a few rough counts to do a quick estimate of rates using the camera’s shutter interval as a timer. I would get three to five every five minute interval giving rates of around 30-60ZHR. Nothing spectacular, just a decent show as the Perseids are so well known for. Though after the true Leonid meteor storm I witnessed in Tucson a few years back anything else does seem a little tame.
As for the photographs? A careful examination of every photo shows a staggering number of meteors were captured by my extensive photographic effort. I had to painstakingly go though each photo to come up with a grand total of…
I did get a nice photo of the Perseus-Cassiopea region of the Milky Way however…