bcmeteors.net

Father of Meteor Allsky Networks, Richard Spalding died Feb 8.

[Excerpts from an article by Tom Dorman.]

Dick passed away Wed, Feb 8 2017, after battling multiple heart issues this past year.  Dick was the Founder of the SkySentinel Allsky Network (Sandia National Laboratories) and was instrumental in setting up and running the meteor fireball camera Systems in the U.S. and around the world.  Allsky camera systems can now be bought off the shelf but back in the 1990’s Dick was giving the camera systems to willing amateurs in support of the North America fireball network.  (Locally he sent Allsky camera systems to a number of nodes in the BC Meteor network in Canada in 2011. )  Dick gave graciously of his time and always was willing to answer questions from even lowly amateurs such as ourselves.

These early camera systems gave a better understanding of meteors, fireball events, meteor showers and their origins. Some of the early fireball cameras that Dick gave out to many amateurs were through DOD grants but many were paid for out of his own money.

Source: http://lunarmeteoritehunters.blogspot.ca/2017/02/father-of-meteor-allsky-networks.html

Lindley Johnson, Planetary Defense Officer at NASA wrote: “He was a great man as well as an insightful scientist and a hero to us all, albeit largely unsung. It is nice to see this latest paper come out and know that he was active to the end in uncovering the mysteries of nature. He will of course be greatly missed, but I hope he was heartened in his last days by seeing us finally making progress in getting bolide reports instituted into our warning infrastructure. In his memory, we will redouble our efforts to make full use of what he had shown us of what is possible to better understand the science of natural objects entering our atmosphere in service of better protection of all human populations and our collective society.”

Source: NASA CAMS: cams.seti.org

The college meteor camera is already seeing more bright meteors zipping overhead. The Perseid meteor shower started July 17, ends Aug 24 but peaks on Thursday night, August 11 and Friday morning Aug 12. If it’s cloudy Thursday, note that Wednesday night and Friday night will also be very active.

This year the Earth will cross the centre of the comet debris; so we should get the full show. We should also get three additional early peaks: Jupiter’s gravity has shifted some debris; and we’ll see debris from the 1862 and 1479 comet ejection trails to hit this year. Peak estimates (by Esko Lyytinen and Mikhail Maslov) are 150 to 160 meteors per hour, about three per minute.

There are four peaks in two waves; we’ll miss the first wave since it hits Thursday in daylight; and the last wave which hits in Friday’s morning light. But the whole night should be pretty constant at 100 meteors/hour. Best seeing times in the East Kootenays would be after midnight once the Moon sets (low in Scorpius) and the skies darken; continuing until dawn at 5am. We’ll miss the last wave at 7am. But these peak times are estimates, we can hope they arrive during darkness instead.

  (Mountain Daylight Savings Time-- minus 1 hr for Pacific) 1.  Thurs Aug 11 at 4:34pm [1862 comet trail] 2.  Aug 11 at 5:24pm [1479 comet trail] 3.  Aug 11 from 6 to 10pm [Jupiter shifts] 4.  Fri Aug 12 from 7 to 9am [Centre of comet orbit].  

It takes the Earth a week to pass through all the ice and dust from comet Swift-Tuttle. The shower will gradually taper off and end by Aug 24. The meteors are travelling at a speed of 59 km/s when they enter the Earth’s atmosphere. Their trails will all point to Perseus (if it’s a Perseid). The closer they are, the smaller their trail: and the further away, the longer the trail. Look for their colours—at high speed they ionize the air to a green; then that fades to yellow, orange, red as it slows down. If they disrupt and flare, you may see green/bluish wide streaks that glow afterward for a second or two (mainly it’s water ice, but there may be metals present like copper or cobalt).

Where to look? The composite photo above shows the entire sky, and all the meteors that fell on 11 and 12 Aug 2015 over Cranbrook; taken by our college meteor camera. Perseus is the constellation to the North East (middle left side of the photo). Normally there are fewer meteors seen straight overhead, since there is less volume of atmosphere overhead. There are slightly more meteors seen high to the West around Hercules and above the handle of the big dipper; since the meteor trails are longer there, and the meteors skim lower in a greater volume of atmosphere. That’s where I aim my cameras. (Or where it’s darkest, away from the Moon or city streetlight glow).

Some of the meteors seen will be from the k-Cygnids running from August 6–19. These peak on August 18 at 3 meteors per hour. They show a number of slow falling fireballs moving at 25km/second.

This photo shows a k-Cygnid meteor crossing through Cygnus the Swan as seen during the last Perseid shower of 2015 (it’s tail is short and it points from Cygnus). Photo taken with a Nikon D100, Tamron 28mm f/2.5 lens, 30 second exposure. I outlined Cygnus in yellow against the Milky Way. The bright star Deneb is the tail at top, and Albireo is the beak at bottom. Photo credit: Rick Nowell.

While you’re out stargazing, here is a starmap showing the Perseus region of the sky, looking Northeast late after midnight in August. The Milky Way band (grey in the map) runs through Perseus; who is the Greek hero coming to rescue Andromeda (daughter of Cassiopeia) who is chained to the rocks. Look below the W of Cassiopeia (the Queen of Ethiopia). You should also see the great square of Pegasus, the winged horse to the right. If you have good eyes (or binoculars), you can spot the fuzzy cloud of the Andromeda Galaxy (M31 in the Map) just above Andromeda’s stick-figure knee. (Andromeda’s head is one corner of the square of Pegasus.) The big dipper, little dipper and Polaris are easy to locate to the left. (Starmap generated by Skyglobe software).

Note: to zoom in a picture or map and see the lines, right-click and open in new tab.

The best and most reliable meteor shower of the year are the Geminids at 120 meteors per hour on early Monday December 14. The second best are the Quadrantids at 120/hr on January 4 but these last only for a few hours. The Perseids are better known, since they occur on August 13 when it’s nice and warm out. But they’re actually number three on the list at 100 meteors per hour.

Since the new Moon occurs on Dec 11, the sky will be dark so we should see even the fainter meteors. The peak should occur around 10am in the morning, Dec 14, persisting for 24 hours. But 2am is fine when the shower’s radiant point, Gemini, rises high in the sky to the East. The meteors are the sand, dust and gravel remains of an Apollo asteroid (3200 Phaethon), coming in at medium speeds of 35km/second. (That’s a medium speed for a meteor. Other meteor shower velocities range from 11 to 72 km/s.) The Geminids come in various colours–65% being white, 26% yellow, and the remaining 9% blue, red and green. They’re active from Dec 4 until Thursday Dec 17. Last night I saw a bright yellow tinted fireball zip across Orion crossing a quarter of the Southern sky, leaving a shorter glowing trail along the last third of it’s flight; and another fireball went across Taurus just two minutes later. Last night I saw a bright yellow tinted fireball zip across Orion crossing a quarter of the Southern sky, leaving a shorter glowing trail along the last third of it’s flight; and another fireball went across Taurus just two minutes later.

Which direction is best to look? Where it’s darkest. As you can see in these composite photos from last year, the fireballs scatter all over the sky, radiating out from Gemini to the East. But when you watch the area around Gemini, the streaks there are shorter and slower moving. These fisheye photos show the whole sky as a circle: North is up, South down, East to the left, and West to right.

These photos were taken from Cranbrook, BC with the College of the Rockies meteor cam.

Below is a starmap looking East around 11pm on Dec 14. Note Gemini the Twins rising due East, just left of Orion the Hunter. Look for two bright stars, Castor over top of the other, Pollux. Gemini the Twins used to be a benevolent guide for the ancient Sailers. In movies you sometimes hear old sailors exclaim “By Jiminy!”. Sirius is the very bright star along the SouthEastern horizon below Orion. Taurus the Bull is the “>” shape above Orion, with the red eye of Aldebaran. The Pleiades are a small fuzzy patch above that.

These pictures are pixelated to fit in this small window–right click and open image in a new tab to zoom in more.

The smoke and haze in Southeastern BC was a problem, but the Allsky Meteor Cam on the Cranbrook College of the Rockies roof still got a dozen bright Perseids or so on the 12-13th. Not 52 like Jeff Brower got on his AllSky meteor cam in Kelowna, by a long shot. This year was a bit better than 2013, although not as many bright fireballs. Below are the brightest ten meteors of the night, all shown on one frame, on the fisheye all-sky view.

I ended up going to the top of nearby Mt. Baker to get above the smoke. South of Cranbrook, just 26km on my tripmeter on a gravel logging road with lots of switchbacks, ending at some radio towers at 7,200 ft altitude. Even up there the horizons were shrouded in haze, and you could see blue haze in the headlights. I couldn’t see Sagittarius at all, no stars were visible below Aquilla. The dim red beacon lights on the radio tower tops weren’t too bright by the picnic table, so that’s where I ended up. I was the only person there, quiet and cool, about 11 deg C. Crickets singing, owls hooting and coyotes howling way off in the distance, motors and fans cutting on and off from the antennaes. Maybe a bat winged over. There are dozens of satellite dishes and radio towers around the hill crest there.

I setup three Nikons and a colour video cam. Left them autoclicking for an hour until the main batteries died, then another hour until the spares died.

Shot of a Perseid meteor streaking through Cygnus the Swan. Deneb is the bright blue-white star above.

Overhead the stars were clear and the sky dark with the Milky Way band glowing. Perseus, Pegasus and Auriga to the East over the Steeples were bright. It was great! The meteors were coming down left and right every fifteen seconds! Some bright ones leaving a glowing line that slowly faded. Mostly white, but some green tinged. Some sporatics that didn’t radiate from Perseus.

That zigzag constellation above is Perseus, with two tiny green meteor streaks radiating from there, red at the ends. There is a fainter third meteor.

Above is a photo of a sporatic going through Cygnus the Swan. Deneb the tail at top, Alberio the beak at bottom. Milky way glow. Shots of Andromeda got nothing except the Andromeda galaxy.

I took these photos with a bunch of Nikon D100 DSLR cameras with Tamron 28mm f/2.5 lenses, and a Vivitar 28mm f/2.0 lens. Exposure times were 30 seconds at 3200 ISO using sunlight white balance. I found I needed at least a f/2.8 lens, since when I used a f/3.3 lens a fairly bright meteor only appeared as a faint streak across the photo.

Rick