From the Field: Double Sun Dogs

On the way home yesterday there were sun dogs on both sides of the sun as it set. 

These are caused by ice crystals in the atmosphere. These tiny crystals act like a giant lens and we see a kind of giant lens flare. 

They always appear 22 degrees to the side of the sun. 

You can learn more about synod phrenic lensing here. http://www.atoptics.co.uk. 

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Monday Phenology: July 4, 2011

Brace yourself sun lovers, the downward slide has begun. The sun rose at 5:31 am this morning and will set at 9:02. That may be a whopping 15 hours, 30 minutes and 51 seconds of daylight but we're losing close to a minute every day. We've lost about 7 minutes since the summer solstice. It sure felt like summer this week with high temperatures, lots of sun and humidity. This is what we dreamed of in February.

This past week:

Monday I took kids down to the lake for a geology class and saw that the beavers were doing a good job maintaining their dam. They are keeping the water about two feet higher in Terrapin Lake as a result of the dam. I estimate that it is holding back about 750,000,000 million gallons of water. That's no small feat! Go beavers!

Tuesday I spent the day at Lilydale Regional park but instead of being focused on phenology I was focused on Geology teaching kids about 450 million year of fossils. I found a fantastic horn coral, a really nice Lambeophyllum profundum. Since it has been dead for almost half a billion years though it hardly counts as phenology. I can tell you that the Poison Ivy is is full effect this summer at Lilydale.

Wednesday morning I noticed the bull thistle is in full bloom in a pasture near work. It is considered a noxious weed but it sure is beautiful to see a large grouping all bloom at once. I'm not sure the holsteins were as impressed as I was.

Thursday I noticed a bee flying around by my back door. It looked at first glance like it was carrying a caterpillar. I watched closely as it flew down to a small hole in my wooden deck railing and went inside. Moments later it emerged again and another bee came back heavily laden with more cargo. They weren't caterpillars at all but rather rolled up leaves. It seems I have a leaf cutter bee nest in my railing. They are docile bees with a mild sting and only sting when handled.

Friday it was crazy hot. Out at work my summer campers and I kept a close eye on the thermometer and around 2:30 or so in the afternoon the heat index reached a maximum of 114.7. I looked around online and didn't find any higher readings anywhere in the metro.

Saturday the leaf cutter bees were still at it and by nightfall there was also a small pile of sawdust near the exit hole. They only excavate rotten wood so they aren't harming the deck. They are important pollinators and a native bee. Interestingly the larva overwinter and do not hatch out until next spring. I'll have to watch for that. While the bees are welcome to stay, I did have to evict four separate paper wasp colonies from my yard. Man they are tenacious and in full on nest building mode this week.

Sunday I spent some time watching a female American Goldfinch gather thistle seeds from my yard for nest building. Goldfinches nest much later than other song birds as they build their nests from thistle seed and must wait for it to ripen. The bird seems to be nesting in a nearby Ginkgo tree. I'm glad all that thistle I can't seem to get rid of is going to some good use.

What to watch for this week.
If you haven't seen the goldfinches gathering seeds for their nest you haven't missed out. A lot of thistle is just barely starting to go to seed so there's plenty of time to witness this event this week. Speaking of seeds, watch for cottonwood trees to dump massive amounts of wind-borne seeds this week. The weather should cool off a bit and be in the 80's. There will be a chance of thunderstorms on Tuesday and possibly Friday/Saturday. Saturn is in the West-Southwest skies just after sunset all this week as is the waxing moon. Both are cool targets though binoculars though the moon will be bright so a pair of sunglasses will help you see more details.

~Kirk

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Monday Phenology: March 28, 2011

Sunrise this morning was at 7:01 AM so we're almost back to having sunrise before 7:00. Daylight Saving Time messed us up in that regard. The last time sunrise seemed this early was back on February 23. Sunset tonight will be at 7:35 PM. We get 12 hours, thirty-three minutes and forty nine seconds of daylight today in St. Paul. Your mileage may vary depending on your latitude. Let's recap last week.

Monday
I hiked down to the lakes at work and there was still ice covering them. You could see slushy spots though. I saw my first Bluebirds at the lake shore. Both a male and female were present and they were checking out an old wood duck box. On Monday I also got a report of the first Turkey Vulture in the Metro on the previous Saturday (3/19).

Tuesday
Common redpolls showed up at feeders in the rain. This was quite a treat on such a dreary day. The winter finch forecast had not been good for redpolls and I didn't see any all winter. On Tuesday I received a late report of both American Woodcocks and Killdeer at a private residence in Hugo back on March 19th! Those were the first reports I's seen of these birds in the metro. Unfortunately, the weather to come was awful and it was a hard week on early migrants. The wind was incredible all day and into the night. It even knocked down the 2000 foot tall TV antenna for WEAU in Eau Claire, Wisconsin. In spite of the awful weather, Kevin in Hastings reported the following species on Lake Rebecca. Canada Goose, Mallard , Northern Shoveler , Canvasback , Redhead, Ring-necked Duck, Greater Scaup, Lesser Scaup,Greater/Lesser Scaup, Bufflehead, Common Goldeneye, Hooded Merganser, Pied-billed Grebe, Great Blue Heron,American Coot,Ring-billed Gull, and Herring Gull.

Wednesday
It snowed all night and through much of the day Wednesday. Accumulation varied widely in a north south pattern. North of the Twin Cities there was over 12 inches of fresh snow. I measured 7 in northern Washington county but only about two inches at home in St. Paul. The biting cold and snow can be hard on early migrants but I did hear that at least on Wednesday morning there were still woodcock poking around and people in the state are even hearing them peenting and seeing them do the sky dance in spite of the cold and snow. I still don't like their odds. I also saw the first report of Fox Sparrows in the metro (in the Lino Lakes area.) They were reported further south over the weekend.

Thursday
Hello Sun! Elizabeth in Hugo reported Song Sparrows, American Tree Sparrows, Pine Siskins and Purple Finches at her feeders as well as a Tree Swallow flying over Plaistad Lake in northern Washington County. There are slow but growing reports of song sparrows around the state. The forecast called for only a high of 28° but the actual temperature in the shade at work was close to 40. By the sunny afternoon there was sap running of out the trees in the sugar bush and I found the first of the year Straight-toothed Sallow (Eupsilia vinulenta) moth feeding on maple sap.

Friday
Another beautiful sunny day. Hearing reports of grackles in Dakota county but nothing widespread yet. Bill in Rochester reported a kettle of Turkey Vultures heading north.

Saturday and Sunday
Flooding is the word of the day this weekend. On Saturday evening water on the Mississippi River started to run onto Harriet Island in St. Paul. The good news is that the cold weather has been locking up a lot of the moisture and the predicted crests are being lowered on many rivers. In St. Paul, the predicted crest is down something like three feet. I saw reports of the first Eastern Phoebe, Swamp Sparrow, Rusty Blackbird and Brown-headed Cowbirds on Sunday. They were along the Minnesota River in Carver County.

The Week Ahead

Flooding will be a big story this week as rivers continue to climb. The Mississippi in St. Paul should crest at 7:00 pm on Wednesday, March 30. Reports of birds will increase this coming week. The birds use the rivers as flyways so those living along the rivers tend to see species a week or two ahead of everyone else. Birds make forays from the river to check conditions inland and start to stick around more as the like what they see. Especially watch for Fox Sparrows and Phoebes this week.

Each day this week will be warmer than the one before it and spring should really feel like it is making a comeback after that snowstorm. April will bring a taste of 50 degree weather by the weekend. Speaking of April, it will be Global Astronomy Month. As a little teaser, look to the East-Southeast this week. In the evenings, Saturn is there for your viewing pleasure. With steady hands and a pair of binoculars you can just barely make out the rings. In the mornings before sunrise, Venus hangs out with the crescent moon all week also in the East Southeast.

~Kirk

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Monday Phenology: March 14, 2011

Sunrise this morning was at 7:29 AM which seems like a step backwards because of Daylight Saving Time. The good news is that the sun now seems to stay up an hour later in the evening. I'm not a big fan. For one, it means I'm putting my kid to bed when the sun is still up which he finds confusing. Secondly, it means evening astronomy programs have to occur so late in the evening that kids have trouble staying up late enough for it to really get dark. I get the idea behind it, that we have more evening light, but by the time summer comes around we have more sunlight than we know what to do with it. Because of Daylight Saving Time, sunset on the summer solstice will be at 9:03 PM and it won't actually get dark until close to 11:36 PM.

Sunset today will be at 7:16 PM and the length of the daylight will be 11 hours, 46 minutes and 28 seconds long. Be sure to make use of those 28 seconds. Every day this week we add 3 minutes and 9 seconds of daylight.

If you missed the planet Mercury last month you still have time to catch it this week. This is one case where daylight saving time may actually help as you'll be home from work "earlier" relative to reality. Mercury is just 2° north of bright Jupiter in the evening sky on the 15th. Look about 45 minutes after sunset. Since we're back to getting up before the sun, look for Venus in the morning sky as well. She's that bright looking "star" in the southeast every morning.

This past week was full of interesting phenology. On Monday, our director spotted a migrating Broad-winged hawk near Scandia, MN. Naturalist Paul Smithson reported a flock of American Tree Sparrows as well. Tuesday we spent some of the day outside getting the sugar bush ready to tap for maple syruping. The buds were swelling on the trees and we heard a lone Canada Goose honking as it flew overhead. We also heard a red-tailed hawk call. Later in the day, I heard the first of the year red-shouldered hawk calling and poked my head outside just in time to see it fly over the building. I'm assuming this is the male from a pair that have nested here for years. Maple syruping is partly so much fun because of all the signs of spring you notice.

Wednesday morning I finally brought my camera along to take photos of all the horned larks along the roads on the way to work. Luckily, we missed the brunt of the big snow storm that day. Some people are probably disappointed that it hurts our chance of a record breaking winter snow total but I, for one, am done shoveling. I'm also not a big fan of hauling maple sap though deep snow.

Thursday morning there was sap in the Maple Syrup bags which means the sap run actually started late on Wednesday. I also received news on Thursday that someone spotted the first Red-winged Blackbird in the Twin Cities. Thursday was also when we discovered a Great Horned Owl had visited the deer carcass we have in the prairie. We caught photos of it carrying of the deer's leg.

Friday, Naturalist Kathy Feste heard the first Sandhill Cranes of the year flying over the nature center. This is earlier than expected. I wasn't thinking we'd hear them for another week. They returned to northern Washington county on March 20th in 2006, 2007, and 2008. This year seems colder than other years so I actually thought they might be a little delayed. Perhaps these were just early birds and we'll start to see larger numbers by the end of the week. I saw my first American Kestrel of the year on Friday as well while driving through Stillwater.

Saturday was colder than I expected and my ears nearly got frostbitten when I went out to the sugar bush with a group of kids. I stupidly didn't wear a hat and it was only about 20° F outside. The little bit of sap in the bags (maybe a half gallon) was all frozen solid and none of the five trees we tapped were running.

Next Week:

Spring should really start to show itself this week. The forecast calls for above freezing high temps for pretty much every day. We should see a dramatic decrease in the snow pack, perhaps helped along by a little rain on Tuesday and a flirtation with 60° on next Sunday. The freezing and thawing cycle from night to day should really get the maple sap flowing this week. I also heard this week that Wood Ducks are in Iowa already. I keep hearing reports of woodcocks peenting in Michigan but it seems a bit early here still. Keep ears and eyes open for Sandhill Cranes, we know they are in the area. If you haven't seen them already, keep an eye open for large flocks of Turkeys gathering in farm fields getting ready to dance.

What are you seeing? Leave comments in the comments section.

~Kirk

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Lunar Eclipse Tonight!

Tuesday, December 21st is the winter solstice, the shortest day of the year. Nature's providing us a special gift to get us though the night. This year, the solstice brings us a Lunar Eclipse visible early Tuesday morning.

What causes an eclipse?
Lunar eclipses occur when the moon passes into the shadow of the Earth. Interestingly, the moon does not completely disappear but rather dims and changes color. It remains illuminated by light that filters though the Earth's atmosphere. It often turns orange but this year some are predicting a blood red moon due to higher amounts of volcanic ash in the atmosphere. One interesting thing to look for is the edge of the shadow on the moon. The shadow has a rounded edge thus demonstrating that the Earth itself is round.

Where to view it.
The eclipse will be visible across North America and the Twin Cities will be no exception. There are a couple of challenges, 1) It will likely be cloudy, 2) It will be cold and 3) it will be late at night.

The current forecast does call for clouds but we'll have to see what actually happens. As far as the cold, a lunar eclipse can be viewed comfortably from inside as long as you can see the moon though a window. There's nothing to be done about the time though. The eclipse begins at 1:41 a.m. CDT on Monday Night/Tuesday morning. It is not a fast event, it takes a while for the shadow to cover the moon. Unlike a solar eclipse, which lasts only a short time, the moon will stay in the Earth's shadow for about an hour.

Backup Plan

Knowing that it will likely be cloudy, die hard lunatics can watch the eclipse streamed live over the web. One option is to open Google Earth. You can click on the planets icon in the toolbar and switch to "Sky Mode.


In the layers panel, open the "Sky Database folder", then open the "Current Sky Events" folder and make sure the "Sloop Space Camera" is checked.


Probably an easier option is to head over to NASA where they are doing a more traditional web stream of the eclipse.

Happy viewing!

~Kirk

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Geminid Meteor Shower December 13-14

The Geminid Meteor Shower will be visible this month in the Twin Cities (the rest of the world as well.) The general "peak" of activity is considered to be on December 13, 11:10 pm central standard time. The good news is that the peak is early so you don't have to be up in the wee hours. The radiant of the shower in the constellation Gemini will be about 50° up in the sky at 11:00 which isn't too shabby so we should see some good action. The closer to the zenith (90° or straight up) the more meteors we see. The "peak" or time of greatest intensity of the shower is actually fairly wide so viewing should be good all night. There is some reason to hope that the Geminids may peak out at up to 120 to 150 meteors per hour this year! Keep in mind though that it will be hard to actually see this many unless you can get ery far awya from city lights. The Moon will be a complete non-factor. Not only will it be only a slim crescent at the time it will also be well below the horizon. The meteors all seem to radiate from the direction of Gemini but they can be heading in any direction from there do you don't need to stare in any particular direction.

The Geminids are a fascinating meteor shower as they are relatively new. They have been increasing over the decades from when they were first discovered. The shower has only been known for the last 150 years. I know I always think of meteor showers as stretching back to antiquity so this is fascinating. Most meteor showers are caused by active periodic comets that circle the sun and leave behind dust trails. The planet intersects these dust lanes and we see "shooting stars" as the particles burn up in our atmosphere. Aside from being new, another reason the Gemenids are interesting is that they are not caused by a comet but rather a strange asteroid called 3200 Phaethon. The source of the Gemenids was a mystery until Phaethon was discovered in 1983. Phaethon has an orbit that takes to from near Mars to extremely close to the Sun. It comes as close to the sun as half the distance from the Sun to Mercury. Phaethon's orbit is slowly changing which is why the shower is becoming more intense. After some time around 2100 the orbit will have changed enough that this meteor shower will have disappeared.

People have asked me where the best place is to view meteor showers in the Twin Cities metro area. That's a tough question. It all depends on how many you want to see. I've seen plenty of meteors from my light polluted St. Paul back yard. Shield your eyes from any stray light such as street lamps and turn the lights off in your house. Most of all, let your eyes adjust to the dark. Fifteen to thirty minutes of letting your eyes adjust to the dark will let you see many many more meteors.

Suppose you want to drive a little though to get a good view? Since my last posting about the Leonid meteor shower earlier this year, I've since discovered a wonderful resource for finding the darkest sky near your location. Check out this wonderful interactive map.

If you look at the map and center in on the Twin Cities of Minneapolis and St. Paul, you can see light pollution is pretty bad anywhere near the metro. What direction to travel depends a little on where in the metro you live. Heading out to an area in the yellow zone on the map will at least give you somewhat darker skies. You need a minimum of a two hour drive to get to a truly dark site and likely it will take even longer. Think boundary waters for true darkness! At any rate, you can most likely easily see a few good "shooting stars." from your own back yard.

The Geminids are beautiful but come at a cold time of the year. Dress warm and post a message in the comments if you see anything good!

~Kirk

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Leonid Meteor Shower November 17th

The Leonid Meteor Shower will be visible this month in the Twin Cities (the rest of the world as well.)

Science has come a long way on these showers to the point that astronomers are getting better at predicting which years will be good and at what exact times the earth will encounter the most dense clouds of debris. The debris that burns up in a meteor shower is from dust trails left by passing comets.

There are two predicted peaks to the Leonids this year. Unfortunately, the best peak will be mostly visible to those in Asia. The predicted peak is 100 meteors per hour. Keep in mind though that these predictions assume you are in a really dark site. Many of the meteors will be faint. A second, less impressive, peak is predicted for North America. The peak will be on the morning of November 17th from 2:30 to 4:30 am CST. That's a pretty vague window but the comet stream that produces this peak is spreading out so the intensity is spread over a longer time period. The Asia peak and the North America peak are from the same comet (Tempel-Tuttle) but from trails left in different years. The predicted rate for the North America peak is about 12 per hour. Look in the southeastern sky. The meteors should appear to come from that direction.

People have asked me where the best place is to view meteor showers in the twin cities metro area. That's a tough question. It all depends on how many you want to see. I've seen plenty of meteors from my light polluted St. Paul back yard. Shield your eyes from any stray light such as street lamps and turn the lights off in your house. Most of all, let your eyes adjust to the dark. Fifteen to thirty minutes of letting your eyes adjust to the dark will let you see many many more meteors.

Suppose you want to drive a little though to get a good view? Check out the Minnesota Astronomical Society website. They have a really cool light pollution map created by Craig Cotner. If you look at the map, you can see light pollution is pretty bad anywhere near the metro. What direction to travel depends a little on where in the metro you live. Heading out to an area in the yellow zone on the map will at least give you somewhat darker skies. You need a minimum of a two hour drive to get to a truly dark site and likely it will take even longer. Think boundary waters for true darkness! At any rate, you can most likely easily see a few good "shooting stars." from your own back yard.

~Kirk

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Top Ten Nature Time Lapse Videos

I've searched the web for the ten best time-lapse videos that show off the incredible workings of our universe. Enjoy. Please vote for your favorite in the comments!

Time lapse video of the Simi Valley fire in California, September 28-29th 2005.



Time lapse video of a huge Amanita muscaria mushroom growing in someone's back yard.


Time lapse video of the Galactic Center of the Milky-way crossing the night sky at the Texas Star Party.


Time lapse video of ants eating a dead lizard. This is nature's recycling in action.


The best aurora time lapse I have seen. An entire night compressed into four minutes. Be sure to check out how much they light up the landscape.


The ubiquitous flowers blooming time lapse.


One year on the Ice. A time lapse showing a year's worth of changes in Antarctica.


One month of coastal erosion in Alaska. This is global warming in action. You can actually watch the thawing land wash into the sea.


The Great Arctic Ice Melt. Only part of this is time-lapse but it shows the impressive change that occurs from winter to summer in the Arctic.


Stunning time lapse of landscapes, sunrise, weather and stars from Japan. Available in HD too!



There you have it. Now scroll back up to the top where the comments link is and let me know which one is your favorite!

~Kirk

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Water on the Moon

At a NASA press conference recently, scientists with Chandrayaan-1 mission revealed fascinating results from the Moon Mineralogy Mapper. The Chandrayaan-1 is a joint project between NASA and India and marks India's first mission to the moon. Chandrayaan is Sanskrit for "lunar craft." The onboard mapper is imaging the entire surface of the moon in high spatial and spectral resolution. It will also reveal the minerals composition of the lunar surface. Results from the mapping were released today and there's a whopper of a conclusion. There's water on the moon. Lots of it.

Well, lots being a relative term. One of the scientists who discovered the water, University of Maryland astronomer Jessica Sunshine said, "If you took a two-liter soda bottle of lunar dirt, there would probably be a medicine dropperful of water in it." That may not seem like a lot to us earthlings who are awash in water but it is significant for the moon.

This news comes just as NASA is about to purposefully crash the LCROSS spacecraft and its Centaur booster rocket into a crater near the moon's south pole so they can analyse the plume they send up. Backyard astronomers with scopes of at least 10 inches may be able to see the impact (or at least the resulting plume) though their telescopes. Impact is tomorrow morning (Friday) at 6:30 AM CDT.

NASA is hoping to find evidence of water in the resulting plume and the confirmation of water by Chandrayaan-1 makes it likely. Why does all this matter? Getting stuff to the moon is expensive. It costs $30,000 for every liter of water NASA ships to the moon. And you thought bottled water was expensive on earth! If we ever build a lunar base, not having to bring water to the moon will save an enormous amount of money. Water can also be split via electrolysis into its primary parts both of which would be useful to a lunar colony. Oxygen is useful for breathing while hydrogen is useful as a fuel. Water on the Moon is a huge step toward a lunar colony.

~Kirk

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Perseid Meteor Shower Imminent

Get ready for a good show Twin Cities. The Perseid meteor shower peaks tonight! You can start watching for shooting stars (meteors) after sunset tonight, Tuesday, August 11th. The show will last all night but the expected peak of activity is in a window of time between 0800-0900 GMT (3:00-4:00 a.m. CDT) on the 12th. Set your alarm clocks for that one! I know it is early but so it goes. The reason for the window is that at that time, the Earth is expected to pass through the filament of dust from comet Swift-Tuttle. Swift-Tuttle is the comet who's dust trail produces the Perseid meteor shower.

There is speculation that this year's show will be particularly good owing to a denser than normal trail of comet debris. Some are predicting rates peaking at 200 meteors per hour which is a fair clip. Of course, if you live in the city you will see far less and the moon will be up at that time with a 61% illumination and about 40° away from the constellation Perseus. Those people outside of the cities will likely see many more meteors.

On a positive note, the radar looks good so far in terms of cloud cover.

~Kirk

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Space Station over the Twin Cities

And now for something completely different. This is the first astronomy related post to the Twin Cities Naturalist. I'm a fan of astronomy and stargazing and strongly consider it part of being a naturalist. There's a great opportunity to stretch your space science geek muscles coming up and I figured I should tell everyone about it.

The International Space Station will fly over the Twin Cities at 11:19 p.m. on July 6th. It is not especially rare to have a fly-over but this one should be good as it will 87 degrees up in the sky so almost right overhead. If you haven't seen it before you should check it out.

I remember the first fly-over I saw was years ago but as the space station grows they keep getting brighter and brighter.

Here's an animation of how the station has changed over the years.

If you miss it there is another pass on the 8th at 10:33 pm that will be only slightly lower elevation (84 degrees)

The ISS passing overhead looks like a really bright star. Don't expect to see much. With a telescope you can actually make out the solar panels. You could try to make out some detail with binoculars. Tracking is tricky and it is bright but some people have reported seeing a few shape details from Earth.

At any rate, it is fun to watch it glide by and to think that there are people living up there in space.

~Kirk

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