RESULTS OF THE JANUARY 2015 ALASKA AURORA EXPEDITION
by Paul D. Maley, NASA Johnson Space Center Astronomical Society
A typical beautiful winter morning view from Taste of Alaska lodge. Photos without credits shown are by Paul Maley.
Our 7th RING OF FIRE EXPEDITIONS aurora viewing expedition to Alaska occurred from January 16-21 to Fairbanks. (Expedition 5 was a site survey trip to Svalbard). We had 9 people on the trip and our base of operations was the Taste of Alaska Lodge located east of the city. The main goal was to view the continuing aurora displays as the Sun begins to wind down from its recent maximum. Temperatures this year were rather mild and the coldest we experienced were on the order of -6 deg F with typical daytime high temperatures around +11 deg F. Of the 5 nights, one had decent aurora and another was clear with no sign of aurora except for two 5 minute outbursts that only two of our expedition members were able to spot. One night was the rather long trip to the Arctic Circle which normally would have been the best opportunity to see the Northern Lights, but on this day it was overcast with light snow and so no aurora were seen then.
Not far away one could go dog mushing. Lynn took a 3-hour course and was able to mush her own team.
Lynn and her team
The dog kennels
Puppies in training
And then there were dogs not quite ready for the task…
Other activities in Fairbanks included a stop at the visitor center
Ice sculpture in front of the visitor’s center
A dragon located at Chena Hot Springs by L. Palmer
The hiking path from the lodge going south. F. Brammer photo.
One of the ready-to-eat meals on the Arctic Circle trip. F. Brammer photo. Only one person dared to try them.
A highlight of our sky viewing was the sighting of a -7.9 magnitude flare from Iridium 70 from outside the Springhill Suites in Fairbanks. With the Sun a mere 5 degrees below the horizon the majority of the group could easily see this bright reflection of sunlight off the main mission antenna at 9.21 am on January 17. Then on the evening of January 18 at 723pm I photographed another flare from Iridium 14 (magnitude -7.9). See next image. The flare appears above Taurus and below Auriga.
Finally on the morning of January 21 at 626am I woke up just minutes before the -5.4 magnitude flare from Iridium 81 and shot this through the sliding glass door of our lodge room. Skies were mostly cloudy but you can make out Arcturus and some of the stars in the constellation of Bootes.
Another viewing highlight was Comet Lovejoy that appeared at magnitude +4 just west of the Pleiades. It appeared as a fuzzy blob, though an extensive tail could not be viewed directly.
I shot the above photo with a 14mm lens and a 30 second exposure. The Pleiades group is seen in the upper left, the comet in the upper right and two satellite trails passing through show up as faint lines.
Here is our intrepid group. From left to right: Yleana Martinez, Florence Brammer, Merrill Deming, Roy Taylor, Katheryn Garlow, Judy Sherrod, Diane Boddy, Lynn Palmer, Paul Maley.
Group image by F. Brammer
Aurora viewing was on everyone’s mind. On January 19 we had our chance. Here are some of the shots Lynn and I were able to capture on our Nikon D3100 cameras using either 11-15mm or 14mm lenses and time exposures ranging from 15 to 30 seconds. In terms of rating the level of aurora activity, when the aurora were seen, the level of activity was low based on our previous expedition experience. Still, this night was impressive for first time observers.
This was taken about 30 minutes after initial sighting of the first faint green glow. In this image there are 3 bands with what appears to be a fourth developing to the lower right. The reddish plume is smoke from the lodge’s heating system. Ursa Major is visible in the upper portion of the photo.
The next image shows the band extending from the initial low elevation in the north over to the western edge of the sky.
Then the band begins to brighten in the east with a bright green glow appearing on the northeast horizon.
Now the band in the western sky begins to demonstrate the start of a curtain. By this time the tripod develops a failure and one leg has sunk in the snow prior to the start of the photo. L. Palmer photo. Cassiopeia is visible in the top portion of the frame.
Then the band in the east also begins to indicate that a curtain may develop. L. Palmer photo. Leo is visible in the right portion of the frame.
Now the band in the west begins to intensify. The red indicates nitrogen, the green oxygen-related emission. Notice the observers in the foreground are concentrating on the eastern sky since the phenomenon is beginning to change rapidly in different parts of the band. L. Palmer photo.
The band begins to change further on a short time scale (seconds to a minute). L. Palmer photo.
In the north the band breaks off with new green glows along the horizon.
In the east, the band intensifies.
The upper portion of the band has moved overhead. The “Big Dipper” is visible in its entirety to the right.
The band in the north has risen and begins to form a large green pillar while the band in the east has coalesced into a very large faint green haze.
The pillar has now begun to change into more of a snake-like appearance.
Meanwhile, back in the west, the aurora has begun to diffuse as it had in the east.
Then, in the north there has been more changes in the overall appearance.
In the west things continue to morph.
The group’s attention stays on the west as it seems something is beginning to happen here as a unique green beam appears.
Then in the north faint green beams appear to the left of the main glows.
But all of these beams begin to fade and all that is left are amorphous green haze. Jupiter is the bright object in upper right.
Time for a portrait under the aurora. Left to right: Merrill, Florence and Yleana. Bootes is visible rising behind the trees.
The aurora ended around 230 after about a 3 hour display.
DIANE BODDY AURORA IMAGES
Nikon D90, f/3.5, 8mm, 13 seconds at ISO 800
At the end of our expedition, Lynn and I flew back to Houston on United Airlines on flight 1104 that departed Anchorage at 1155pm on January 21. By instinct I wanted to see if aurora could be seen from the aircraft windows. We were seated on the south facing side and so I got up and went to the north facing window at the front galley and took this photo. The window is quite small with the outline visible. However, when I looked out I could see a faint green band extending from horizon to horizon. It too was low activity aurora and there was nothing more than that for the 20 minutes or so that I kept watching. In the photo below the constellation of Draco is visible. It was shot with the camera hand held to the window for about 6 seconds.
My last aurora shot from a Boeing 737 at 32,000 feet above southeast Alaska
Perhaps the most interesting sky event was the eclipse of the 10.9 magnitude star TYC-2334-00124-1 by the asteroid 704 Alauda on the evening of January 19 at 650pm. The path of this occultation very fortuitously crossed Fairbanks and also the lodge. This was an opportunity to accomplish some real science by helping to map the two dimensional shape of this asteroid by timing the disappearance and reappearance of a star as the asteroid passed between the star and the Earth. At this time Alauda was 211 million miles from us. Alauda was the 702nd asteroid ever found and it was discovered by an astronomer in Germany in 1910.
The diagonal parallel lines show the predicted path of the eclipse from Alaska to Baja, Mexico.
Anticipating the difficulty in observing and recording the event with battery powered equipment I worked with members of our group to assemble a fool proof plan. Alauda is about 194 km in diameter and its orbit is reasonably well known; therefore the likelihood of us being under the asteroid shadow was quite high. However it was snowing all day and as the clock ticked down, the clouds began to thin about 1.5 hours before the event. At 445pm we held a meeting to discuss the objective and I solicited ideas from the team to overcome the temperature, walking path, antenna protection strategy, telescope focusing and battery challenges. Photos were taken of all aspects of the eclipse process. It was very uncertain if any stars would be seen through the cloud cover. But, at around 530pm I saw one or two of them appear. My thought was to set up the 120mm diameter refractor just outside the sliding glass door of my room; then, to run video and power cables through the opening in the door to the GPS receiver and camcorder located inside the room on the opposite side of the door.
The first image above by Y. Martinez (who designed this path!) shows the trash bag walking path between my room and Florence’s which I used to go in and out of the building. The next photo shows Yleana laying down the start of the path (photo by L. Palmer)
The GPS antenna, about 12 feet in length, was run to the outside so it could see the sky. Since the temperature at occultation time was +4 deg F I was concerned about protecting the wire as well as the rest of the equipment. Members of the team (Judy, Yleana, Merrill, Diane,Lynn and Florence) came up with some very creative ideas without which the operation would not have succeeded. With me outside positioning the video camera on a particular star field, Lynn (on the inside of the room) flagged when the focus was just right. Yleana laid down plastic trash bags from the adjacent room through the hall and into my room so I could walk through the snow inside and back out without wasting time donning and offing snow boots.
The above image shows the heater used to warm the area around the camcorder and GPS receiver. As it turned out the heater was not necessary as the door seal was more than adequate. Y. Martinez photo.
A wool blanked was stuffed between the top of the door and door frame extending to about 4 feet above the ground. Merrill, after setting the blanket in place and wedging the Styrofoam at the bottom of the door, had to hold the door shut for more than 30 minutes using her hand/body! Y.Martinez photo. Kory Eberhardt kindly provided the heater, extension cord, wool blanket and Styrofoam from his stash of hotel supplies.
The door seal worked so well that there was only a 3-inch gap between the Styrofoam and the blanket allowing for free passage of the cables. L. Palmer photo.
This scheme worked really well. Judy came up with the idea of using sleeping bags on chairs as a support structure for the GPS antenna. These were laid out along the entire length of the antenna. Even though the far north part of the sky was blocked, the GPS satellites were well in view of the antenna the entire time.
The GPS antenna is seen with its mostly all sky view (pointed south) propped over a chair. Initially it was sitting on the chair but there was interference from the metal sides. Once it was repositioned, the GPS signals cleared up. In addition you can see the line of chairs, me and the telescope adjacent to the door. Y. Martinez photo.
The first image above shows the ‘target star’ being observed (identified by the + sign). The one below that is a downward view into the briefcase with the star chart, camcorder (lower right), GPS box (with red LED), and envelope containing 8 AA batteries) that provided power to the GPS and camera outside. Y. Martinez photo.
A hair dryer was employed to zap the gears on the telescope in case they froze. There were two manual slow motion controls on the scope that I used to position the pre-point star and then let the Earth do the rest of the work. At precisely 650 the target star passed through the center of the field of view. The sky was partially clear, yet the target star COULD NOT BE SEEN! Several reference stars were visible in the camcorder view screen. All equipment performed as planned and a video recording was made with time inserted on the tape. I was quite concerned that either no data could be obtained or that no occultation had taken place since we could not see any evidence of the target star.
As it turns out this proved unfounded. Through the efforts of Tony George and Brad Timerson, a successful reduction of the uploaded video was made and the resulting chord obtained (along with two other positive observations by observers in California and several miss observations) fit perfectly with the the simplistic two dimensional model. Of course asteroids are not spherical which is why additional data points would have been helpful in providing additional resolution at this moment in time. Alauda rotates once on its axis in 8.3 hours, so the profile would appear different depending upon where it was within its rotational cycle.
In the above graphic, the sky plane is shown with a circular model shape (yellow). The dotted line represents the view from the predicted center of the eclipse path. The lines that do not intersect the circle are from observers who saw no occultation. Chords labeled 5 and 6 on the west side of the asteroid observed a brief occultation. However, our Fairbanks site experienced a 15 second eclipse.
Our final phenomenon was a Sun pillar. Formed from ice crystals in the atmosphere that have horizontal surfaces. The pillar appears as a vertical column of light extending below the Sun in this case about 10 degrees. Although the photo appears to show it as vertical, in fact, we observed this column to be in front of us on an ice pond. So, this particular one is slanted toward the observer. As time passed and the Sun appeared to move farther to the west, the pillar remained intact for more than an hour and moved westward along the ice pond.
The Sun itself is seen through a veil of cloud with the distance between the central image and the image on the pond equidistant.
The same sun pillar is seen about 20 minutes earlier. D. Boddy photo.