Epsilon Aquilids

This meteor shower is apparently only visible with some optical aid, as no visual or photographic detection has ever been made.

The discovery of the Epsilon Aquilids should be credited to B. L. Kashcheyev and V. N. Lebedinets (Kharkov Polytechnical Institute, USSR), who detected 17 radio meteors from this stream during May 4-27, 1960. They determined the date of the nodal passage as May 17, at which time the radiant was located at α=276°, δ=+13°.

This stream was again detected in 1969, during the second session of the Radio Meteor Project. Despite Zdenek Sekanina giving the duration of the Epsilon Aquilids as May 19-21, it should be noted that the radar system at Havana, Illinois, had been shut down during May 10-18, so earlier members might have been missed. Sekanina gave the date of nodal passage as May 20.3, at which time the radiant was at α=284.1°, δ=+15.5°. Both the date of nodal passage and the radiant might have been altered had the radar been in operation during mid-May.

Orbits computed from both sets of data are very similar and with their semimajor axes both being less that 1 AU, they seem to hint that the body responsible for the stream formation is moving in an Aten-class asteroid orbit.

As noted earlier, no apparent visual observations of this stream appear in any records of the last 150 years. The primary sources checked by the Author are the papers of W. F. Denning, A. King, and R. A. McIntosh, C. Hoffmeister's 1948 book Meteorströme, and over 6000 radiants of the American Meteor Society. Papers checked which contain photographic orbits include those by F. L. Whipple, R. E. McCrosky, A. Posen, P. B. Babadzhanov, E. N. Kramer, and Z. Ceplecha.