The annual Geminid meteor shower has become one of the most reliable annual meteor showers. First observed over 150 years ago this is a interesting meteor shower. The parent body for the Geminids is not a comet, but rather the asteroid 3200 Phaethon. It is somewhat of a mystery how this mostly rocky body gives rise to the debris stream needed to generate a meteor shower.

The evening of Dec 14th into the morning of Dec 15th is favored, starting around 8pm as Gemini rises in the east.

While the 2011 Geminids are expected to just as numerous as usual, viewing will be hampered by a bright Moon in the sky. Certainly the brighter fireballs will be easily visible, but the dim meteors will be lost to the moonlight. If you do wish to try your luck, view between midnight and dawn on the night of the 14th and into the morning of December 15th. It may be possible to see some meteors after the radiant rises, about 8pm, and before moonrise around 10pm on the evening of the 14th.

Watching meteors requires no more equipment than your eyes and a dark sky, and can be enjoyable for just about anyone. Set the alarm clock, this one should be worth the early morning wake-up.

Leonid Meteor Shower

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.

1833 Leonids
1833 Leonids, the engraving is by Adolf Vollmy based upon an original painting by the Swiss artist Karl Jauslin, that is in turn based on a first-person account of the 1833 storm by a minister, Joseph Harvey Waggoner on his way from Florida to New Orleans.
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.

Meteor Fireballs

Thanks to all of those folks who posted comments about meteor fireballs. As I mentioned, these sort of events are not all that uncommon, and occur regularly across the globe. What is unusual is good photos of the event. This did happen this week, a photographer had a good camera at the ready when a similar fireball came in over Groningen, Netherlands on October 13th. Great photos of an event much like the one we saw last week over Hualālai. Check out his page for the full set of photos including the final breakup, the website is in Dutch, but a Google translation will let you follow the description.

Mikaelyan Meteor
A meteor breaking up over Groningen, Netherlands, 18:57, 13 Oct 2009, photo by AndrewPosted on Categories Meteor ShowersTags , Leave a comment on Meteor Fireballs

Fireball Over Hualālai Update

Looks like several folks saw this meteor come in, including the entire evening crowd at the VIS. Another report from Kali on Maui emphasizes just how bright it was.

Larry O’Brian reports from the VIS…

The highlight of the evening was unquestionably a spectacular fireball that burned brilliant green, slow- moving, threw off at least one fragment, the whole enchilada. No sound, other than thirty people shouting ‘wow!’ I first caught it around, say, Aquila heading towards Ophiuchus, but people were already calling out about it.

Between Larry’s excellent report and my own sighting I can place this meteor coming in steeply somewhere over or just south of Hualālai. From around the summit to out to sea beyond Kealakekua, much closer than I would have thought. Given the breakup and low altitude the proximity implies there could have been pieces reaching the ground. Anyone in South Kona report something hitting their roof?

Any readers want to join me search an entire 9,000ft volcano for meteor fragments? Spotting dark fusion crusted meteors on top of fresh black a’a basalt ought to be easy… Not!!!

Fireball Over Hualalai

Nice meteor fireball just a few minutes ago. Just as Deb and I were driving down Waikoloa Road, about 8:06pm, due south over Hualalai. It lit up the landscape a bit, very bright, with fragments flying off as it came in.

Given the time, mid-evening with dinner events and Iron-Man festivities underway, I suspect more than a few people along the coast noticed this one.

Of Pu’u and Perseids

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…

Cassiopeia and Perseus
Cassiopeia and Perseus region of the outer Milky Way, Canon 20Da, 14 5min exposures stacked, M31 and the Double Cluster are easily visible