Some calendric information on the IGY

The comment on my last post was: "did you ever explain why the international geophysical YEAR was 1.5 years long? As Jerry Seinfeld would say, what's the deal with that?"

So, here is the deal, and some other chronological information about the IGY.

Why did the IGY "year" last 18 months, from July 1, 1957 to Dec. 31, 1958? A NOAA history of the IGY says: "Scientists timed the IGY to coincide with an expected peak of sunspot activity and several eclipses. An 18-month long IGY would allow scientists to sample all of these solar events, as well as conduct other timely research."

The expectation turned out to be correct, as you can see in the top graph of sunspot numbers below from the WDC-SILSO (Sunspot Index and Long-term Solar Observations). Note the highest number in the entire sunspot number record occurs during the IGY in 1958. This was solar cycle 19 (solar cycle 1 began in 1755); details without smoothing are shown in the bottom graph.

Yearly mean sunspot number (black) up to 1749 and monthly 13-month smoothed sunspot number (blue) from 1749 up to the present

Unsmoothed solar cycle 19, during the IGY (https://weather.plus/solar-cycle-19.php)

NASA instructs us that the Sun is a huge ball of electrically-charged hot gas. As this charged gas moves, it generates a heliomagnetic field. This magnetic field goes through a cycle of oscillating amplitude, called the solar cycle. (By the way, I often use a hotlink rather than quotes when I borrow text from another source.) After each solar cycle of 11 years or so, the Sun's magnetic field flips polarity, i.e., the Sun's north and south poles switch, somewhat like geomagnetic reversals on Earth (although these take place only several times per million years). Then it takes about another 11 years for the Sun’s poles to flip back again. The solar cycle affects activity on the sun's surface, such as sunspots which are caused by the Sun's magnetic fields. Solar activity also radiates into space and towards Earth via the solar wind (not the SolarWinds hack), so is responsible for "space weather," geomagnetic disturbances, and the aurorae in the Earth environment.

Solar activity is related to at least four of the areas of focus of IGY study: World Days [when measurements are mad around the world] and communications; geomagnetism; aurora and airglow; ionosphere; solar activity; cosmic rays.

The following IGY calendar is from a book in my library (one day I will have a catalog to share), IGY: Year of Discovery, Sydney Chapman, University of Michigan, 1959, p. 103). You can also find this calendar online here. 

The calendar shows:

World Meteorological Intervals - special weather observations made on each of 10 consecutive days, every three months; 

Regular world days - three per month when extensive (worldwide) multidisciplinary measurements were made;

Regular world days at monthly new moons;

Unusual meteoric days;

Regular world days with unusual meteoric activity - e.g., the Perseid meteor shower, Aug. 12, 1957;

Days of total solar eclipse - Oct. 23, 1957; April 19, 1958; Oct. 12, 1958.

The IGY favored synoptic measurements, i.e., when similar measurements are made at the same time in different locations to better characterize the global environment. 

Note that extra months in the calendar are included before and after the already 18-month "year" (please don't ask me why). In addition, the success of the IGY led to an extended follow-up period continuing through 1959 at a reduced level of activity, called the International Geophysical Cooperation.

As per the IGY, space weather measurements not made continuously  are concentrated and coordinated on specified days, published annually as archived here by the National Geophysical Data Center.

Even before the IGY was over, it was clear to scientists working in the upper-atmosphere disciplines that certain observations should be continued at least through the waning period of the solar cycle, and that others should be repeated at solar minimum. Thus it was decided to conduct another full-scale international program in those disciplines during the following  solar minimum. Thus emerged a new international enterprise, officially designated the International Years of the Quiet Sun, which took place during 1964 and 1965 (International Years of the Quiet Sun, 1964-65, Martin A. Pomerantz, Science, v. 142, 1963, p. 1136-3). You can see the low sunspot number for that period in the graph above. There was no U.S. postage stamp issued for this, although there are IQSY covers from the U.S. and  IQSY stamps from other countries.

I thought of closing with a Seinfeld clip, maybe on Newman, since he was a postal worker. Instead, I came across this music video of John Newman singing Love Me Again, which I remember enjoying in the breakfast room of the Sultan Royal Hotel in Istanbul in 2014. It has nothing to do with anything I should be writing about. I bet my editor, who was there with me, won't remember this.