Solar eclipse of June 30, 1992

The path of totality was mostly on the sea and covered very little land. From the only land covered by it in southeasern Uruguay and southern tip of Brazil, totality occurred shortly after sunrise, with the solar zenith angle less than 3°. Observation from an airplane over the middle of South Atlantic Ocean, near the location of maximum eclipse, could offer a duration of totality of up to 10 minutes with the guarantee of clear weather. However, due to the limitations in the cruising capabilities and the economic cost, a feasible flight plan was to see 5 to 6 minutes of totality on the airplane. 48 people from the United States, Canada, Brazil, Germany, Japan and Great Britain boarded a VASP airline DC-10 plane, departing from Rio de Janeiro, Brazil, flying over the South Atlantic Ocean and returning to Rio de Janeiro. The passengers got off and the captain flew the airplane back to Sao Paulo. Although adjustment in the flying speed had to be made according to the take-off time and wind speed, the pilot flew the airplane into Moon's umbra within 1 second of the predicted time, and the passengers on board successfully saw the total eclipse. Accidentally, one of the ground support personnel did not exit the airplane before takeoff, and she also saw the eclipse. The pilots were also attracted by the eclipse, still watching the moon shadow moving into the distance and forgetting to fly the airplane back return even minutes after the third contact (the end of the total phase). The captain described this as the most unusual flight he ever commanded. VASP airline also provided a Boeing 737 plane to the Rio de Janeiro Planetarium [pt]. Planetarium staff, of their astronomy club, local dignitaries, politicians and celebrities were also invited.^[1]

• An annular solar eclipse (ascending node) on January 4.
• A partial lunar eclipse (ascending node) on June 15.
• A total solar eclipse (descending node) on June 30.
• A total lunar eclipse (descending node) on December 9.
• A partial solar eclipse (ascending node) on December 24.

This eclipse is a member of a semester series. An eclipse in a semester series of solar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternating nodes of the Moon's orbit.^[2] This semester series contains only 7 eclipses.

It is a part of Saros cycle 146, repeating every 18 years, 11 days, containing 76 events. The series started with partial solar eclipse on September 19, 1541. It contains total eclipses from May 29, 1938 through October 7, 2154, hybrid eclipses from October 17, 2172 through November 20, 2226, and annular eclipses from December 1, 2244 through August 10, 2659. The series ends at member 76 as a partial eclipse on December 29, 2893. The longest duration of totality was 5 minutes, 21 seconds on June 30, 1992.

This eclipse is a part of the long period inex cycle, repeating at alternating nodes, every 358 synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee). However, groupings of 3 inex cycles (≈ 87 years minus 2 months) comes close (≈ 1,151.02 anomalistic months), so eclipses are similar in these groupings. In the 19th century:

• Solar saros 140: total solar eclipse of October 29, 1818
• Solar saros 141: annular solar eclipse of October 9, 1847
• Solar saros 142: total solar eclipse of September 17, 1876

In the 22nd century:

• Solar saros 150: partial solar eclipse of April 11, 2108
• Solar saros 151: annular solar eclipse of March 21, 2137
• Solar saros 152: total solar eclipse of March 2, 2166
• Solar saros 153: annular solar eclipse February 10, 2195

This eclipse is a part of a tritos cycle, repeating at alternating nodes every 135 synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee), but groupings of 3 tritos cycles (≈ 33 years minus 3 months) come close (≈ 434.044 anomalistic months), so eclipses are similar in these groupings.

The metonic series repeats eclipses every 19 years (6939.69 days), lasting about 5 cycles. Eclipses occur in nearly the same calendar date. In addition, the octon subseries repeats 1/5 of that or every 3.8 years (1387.94 days). All eclipses in this table occur at the Moon's descending node.

• Earth visibility chart and eclipse statistics Eclipse Predictions by Fred Espenak, NASA/GSFC
  • Google interactive map
  • Besselian elements