The entrance to Poker Flat

The Poker Flat Research Range had its 50th Anniversary party over the weekend, and Fairbanks residents showed up in droves to celebrate. I think it is safe to say that Fairbanks is quite proud of its far-north launch facility. I was amazed at how many people came out for the event.

Owned by the University of Alaska-Fairbanks Geophysical Institute, Poker Flat is the world’s largest land-based rocket range. The 5132 acre site is located 30 miles from Fairbanks, just north of Chatanika, on the Steese Highway, where Poker Creek flows into the Chatanika River.

More than 300 major, high altitude rockets and 1800 meteorological rockets have been launched from Poker Flat to study the Earth’s atmosphere, and the interaction between that atmosphere and the space environment. The rockets launched are sounding rockets, which are designed to operate between the height that a weather ballon can reach, yet below satellites. Sounding rockets are relatively low cost, with a quick lead time, which is advantageous in the world of research.

NASA launches a sounding rocket at Poker Flat; Photo credit: PFRR

NASA, Wallops Flight Facility, the Department of Defense, and many universities world-wide, have launched rockets from Poker Flat.

A recovered payload from a March 2017 launch

One busy week at Poker Flat had four launches in 33 minutes during a night with high aurora activity. One mission saw two rockets launched to measure the turbulence in the upper atmosphere: was it two dimensional or three? Also measured were air density along the rocket’s parabola, which had an apex of 100 miles above northern Alaska. Also measured was the lowest reaches of where the aurora interacts with the upper atmosphere.
On the same night, two rockets from Clemson University launched. These rockets released a white vapor, trimethyl aluminum, so that researchers could visualize the turbulence 60 miles above the ground.
Not to be outdone, two nights later, a rocket launched for Utah State that released instruments to measure the voltages and currents in the aurora display over Kaktovik, Alaska.

Weather balloons ready to launch

I’m glad I arrived early, because I think turn out was greater than expected. After visiting the main offices, I walked down to where the shuttle busses were hauling people to the various sites. Poker Flat is fairly spread out, plus there was a cow moose and a calf wandering about, and officials seemed wary that someone could get stomped. Weather balloons were launched every 15 minutes or so, which I watched while waiting for a shuttle. Turns out there is an advantage to attending things like this solo. A University police officer offered rides to the upper facilities, and he had room for three. The first couple climbed in, and I seemed to be the only single paying attention, so I volunteered to climb in the back of the squad SUV.

Some NASA & PFRR “Rocketeers”

The facility is really quite impressive. I was able to talk to several NASA scientists, as well as some Poker Flat “rocketeers”. Everything was available to view, from the radar screens to the “catwalk” outside, and the green lidar beam, which is part laser and part radar, and is shot 50 miles into the sky. There wasn’t one person involved with the sounding rockets, that didn’t get excited talking about what they did, or what they had planned for next year. The representative from Wallops told me they were excited now to get down under to Australia to launch rockets next. It will be their winter soon, and they had some rockets designed that would open in the back with telescopes to get images of the southern sky.

A NASA launch as viewed by the Poker Flat Skycam; Image credit: PFRR

One thing about the aurora borealis that is not widely known, is that, due to the Earth’s magnetic field, what we see here in the northern hemisphere, the southern hemisphere sees the mirror image of. I have always found that fascinating.*

Early artwork of auroral display

The earliest written record of an auroral display was from 567 BC on a Babylonian clay tablet. The tablet describes a “red glow in the sky” lasting two hours. The red aurora was often thought of as an evil omen in medieval times. Nearly all northern native cultures associate the aurora with spirits of the dead.

Some statistics from PFRR:
First launch: March 1969
Heaviest rocket: Aries – 11 tons
Longest rocket: Black Brant XII – 85 feet
Heaviest payload: 2200 pounds
Highest altitude flown: 930 miles
Distance downrange: 1100 miles
Rocket acceleration: 17 Gs
Rocket speed: Mach 2

The view from a very bouncy squad SUV. The ride is not as comfortable as one might think.

The peak season for launches at Poker Flat is between January and March. Most often launches occur when the aurora is going, and the moon is down. Cleary Summit is a great place to watch and/or film a rocket launch. Poker Flat also streams launches live on its youtube channel.

The line for the shuttle bus, or the reason I took the police car; Image credit: PFRR

*See: Rockets Over Alaska: The Genesis of Poker Flat by Neil Davis