Thursday, October 14, 2021

IGY Bulletin, Number 3, September 1957 - Aurora and Airglow Program; Rocket Program

Ok, I'm finally at the last two articles from the September IGY Bulletin, then I can move on to October and be in the right month again.

Aurora and Airglow Program

The altitudes of these two atmospheric phenomena are about 150 km for the aurorae and 100 km for the diurnal airglow, respectively, shown in a graphic from an earlier post, corresponding to the middle atmosphere and the lower ionosphere. (Recall that 1 mile = 1.6 km, or 1 km = 0.6 miles.) 

The airglow is a faint optical emission due to interactions of sunlight with atmospheric chemistry. On the other hand, aurora emissions are driven by atmospheric reactions with energetic electrons in the magnetosphere that originated in the solar wind. I've only seen one aurora -- in 1994 I think, keying that to a family trip where we had seen a Toronto Blue Jays (younger son Sam's favorite team at the time) game right before the end of the strike-shortened baseball season -- when we were camping outside Ithaca, NY. My older son Max remarked on some lights in the sky, which I attributed at first to some spotlight, but was eventually convinced otherwise. Ha ha, that reminds me that Max also noticed a total lunar eclipse that I was unaware was going to happen when we lived in Germany during my first sabbatical in 1989-90; that must have been on Feb. 9, 1990. Ok, now that I am on eclipses, two years from today there will be an annular eclipse of the sun in the southwestern Southwestern U.S., and in 2.5 years a total eclipse of the sun visible in the northwestern part of my state of Pennsylvania. Start planning.

Anyway, the Bulletin article discusses plans to observe aurora during the IGY by photographing the whole sky with 29 cameras deployed in high northern and southern latitudes. With film(!), if you young folks know what that is. And here is a cool word from the article: ascaugraph - an instrument for the semi-automatic reduction of all-sky camera films, constructed for the IGY. I can't even find that word by googling.

The aurora were also to be observed visually at 120 U.S. Weather Bureau (employer for my second summer job, I'll save that for another time), and 56 volunteer stations. Yay for citizen science. Spectrographs (to look at emission colors, or spectra) and other instruments were also to be used.

Here is a more recent (Feb. 18-19, 2014) spectacular video display of the Northern Lights in Alaska (you can turn the music down):

Rocket Program

Experiments discussed in other articles in this issue of the Bulletin for studying solar activity, ionospheric physics, geomagnetism, aurora and airglow were ground-based or made low in the atmosphere. Rockets as a research tool would also allow observations to be made from higher altitudes, without the hindrance of atmospheric screening. Sounding rockets (exploring vertical stratification) were to be used during the IGY to make observations of the atmosphere, ionosphere and magnetosphere at different latitudes, but especially from the newly established complex at Ft. Churchill, Canada, located in the middle of the auroral oval zone where the aurora are most prominent. The U.S. Department of Defense and the Canadian government cooperated in establishing the launching complex and associated instrumentation at Ft, Churchill. Pre-IGY tests were make with 19 small rocket flights and 5 Aerobee rocket flights.

Many Aerobees were launched from the White Sands Missile Range in New Mexico. Check out the history of the Aerobee rocket in this video from the New Mexico Museum of Space History:

I don't have anything to say about William Shatner's rocket trip into space. I guess I'm just not interested. But I find another Rocket Man's journey, which I just watched for the first time, quite beautiful and compelling. Iranian filmmaker and refugee Majid Adin's  reimagination of the Elton John song tells a story of adventure, loneliness, and hope:

Saturday, October 9, 2021

The anniversary of the launching of Sputnik, the first artificial Earth satellite

I was away for 10 days on my longest trip in the covid era. I spent a couple of days in Acadia National Park (Maine), ate a whole lobster (not sure f I ever did that before), toured the Peary-MacMillan Arctic Museum at Bowdoin College and the Mystic Seaport Museum in Connecticut (and ate non-Mystic Pizza pizza while watching the movie Mystic Pizza), visited with three former students, heard my son give a lecture at Susquehanna University, and explored the ups and downs of public transportation (including a delayed Amtrak train due to an accident on the tracks, causing me to take my longest Uber ride ever to get into New York on time). 

I'll get back on track on reporting articles from the IGY Bulletins of 1957 with the next post.

But today I want to honor the launching of Earth's first artificial satellite, Sputnik, on October 4, 1957. NASA's web page on Sputnik and the Dawn of the Space Age states, "History changed on October 4, 1957, when the Soviet Union successfully launched Sputnik I. The world's first artificial satellite was about the size of a beach ball (58 cm.or 22.8 inches in diameter), weighed only 83.6 kg. or 183.9 pounds, and took about 98 minutes to orbit Earth on its elliptical path. That launch ushered in new political, military, technological, and scientific developments. While the Sputnik launch was a single event, it marked the start of the space age and the U.S.-U.S.S.R space race."

Below is a newsreel from back in the day, with its very retro style. (For some reason Fox News is spinning over the video, even though that purported purveyor of news did not yet exist.)

The Story of the Sputnik Moment by David Hoffman is a longer exploration of the American perspective and cultural context of the launching of Sputnik.

The film was based on Paul Dickson’s book Sputnik: the Shock of the Century (2001).

Another documentary is from the PBS Nova Series, Sputnik Declassified. It posits that President Eisenhower had other plans for the use of space. See that one here.

In my opinion, these documentaries are a little naive in terms of the disbelief of Americans who could not conceive that the Soviets could ever beat America with such a technological accomplishment. 

As the Pravda announcement of the launch states, the Soviets had planned to launch satellites during the IGY, as had the U.S. Both were successful, but the Soviets were first. Pravda added, "The successful launching of the first man-made earth satellite makes a most important contribution to the treasure-house of world science and culture. The scientific experiment accomplished at such a great height is of tremendous importance for learning the properties of cosmic space and for studying the earth as a planet of our solar system."

My Sputnik memorabilia items include:

  • a signed copy of Dickson's book on Sputnik.

  • statuettes my parents brought me after they visited the Soviet Union and my Dad's childhood home in 1964
Each about 2" across. The one on the left, with a little repair clay on it), says 4-X-1957 [date of launch] CCCP [Russian for USSR] on the base. The one on the right has CCCP on the globe, and some text on the base which is difficult to read; I'm not really sure if this one is Sputnik 1 or another satellite/rocket.

  • a number of postage stamps, such as Russia (Soviet Union) Scott catalog #1992, with the launch date text "4 October 1957" and "first in the world, Soviet artificial earth satellite," 40 kopeck, issued 5 Nov. 1957, just a month after the actual launch of Sputnik.

I'll return in future posts to Sputnik 2 (launched 3 Nov. 1957) and  Sputnik 3 (15 May 1958), both launched during the IGY, the only other satellites designated by the Soviets as Sputniks. The Russian covid drug is named Sputnik V. Obviously, the name is still used to convey prowess and success.

Saturday, September 25, 2021

IGY Bulletin, Number 3, September 1957 - Ionospheric Physics Program

The next article in this issue of the IGY Bulletin introduces plans for the Ionopsheric Physics Program. The main part of the program was to send vertical radio wave pulses into the ionosophere that would be reflected back to the Earth's surface and recorded as ionograms. (If you've ever picked up radio stations from hundreds of miles away, that's due to radio waves reflected from the ionosphere, although not vertically.) Unique relationships exist between the frequency of the waves and the electron densities which can reflect it. As the signals sweep across different frequencies, they are reflected from the different layers of the ionosphere. Altitude of the different layers of the ionosphere can be derived from the up-down travel times of the waves. Electron densities in the layers can also be inferred from how much of the upgoing radio wave energy is absorbed before being returned to Earth.

More information on the ionosphere can be derived from naturally occurring radio pulses which originate from lightning discharges, also called sferics. Specific types of sferics are called tweeks and whistlers.

This "sounding" of the ionosphere is somewhat analogous to using seismic waves to probe different layers in the subsurface of the solid Earth. Like with ionosphere probing, the seismic soundings can be based on natural waves from earthquakes, or artificially induced seismic waves, depending on the nature of the study. I've often been impressed how the physics of waves are applicable to so many different phenomena.

The details of the rest of the article are more technical than you (or I) will want to get into, so let's leave it at that.

One international society that focuses on both internal and external aspects of the Earth's magnetic field is the International Society of Geomagnetism and Aeronomy (IAGA). IAGA is organized into six divisions: internal magnetic fields; aeronomic phenomena; magnetospheric phenomena; solar wind and interplanetary field; geomagnetic observatories, surveys and analyses; electromagnetic induction in the Earth and planetary bodies. Aeronomy is a term we haven't encountered here yet; it deals with "the dynamics, chemistry, energetics and electrodynamics of the atmosphere-ionosphere system as well as the coupling processes." 

I've been to a number of IAGA meetings which meets every two years, alternating between its own Special Assembly and joint General Assemblies with seven other international scientific associations that are all part of the International Union of Geodesy and Geophysics (IUGG). The IUGG  is a non-governmental, scientific organization established in 1919 for international promotion and coordination of scientific studies of the Earth (physical, chemical, and mathematical) and its environment in space. 

One of the meetings I went to was IAGA 2009 in Sopron, Hungary. A related stamp was made available to us at the meeting. I bought a pane, and also sent a cover to myself back home. "Magyarország" on the stamp just means Hungary, and "Belföld" is domestic (hence more stamps were added to make up the international rate. I think the instrument in the image is a sun compass. Notice that the selvage (margins of the stamps) on the pane commemorates the meeting.

Pane of stamps with "IAGA" in the selvage of the stamps, and a plate number in the selvage of the pane

Front of IAGA 2009 postcard sent home, with the IAGA postmark

Back of the postcard, showing the conference venue, the Liszt Ferenc Conference and Cultural Center

IAGA recently started a blog for promoting the work done by the IAGA community and portraying the life of its researchers. The blog is maintained by the Social Media (SM) Working Group in order to provide an easily accessible platform for news and information and to act as a bridge connecting the scientists and their research with the general public. I am pleased that the IAGA blog gives this blog a shoutout in its latest post. Thanks to Shivangi Sharan for connecting with me.