History
The data supporting this stream’s existence is mainly concentrated in three radar studies conducted during the 1960’s.
During June 13-19, 1961, C. S. Nilsson (Adelaide, South Australia) detected four radar meteors from α=293.9°, δ=-8.4°. A second radar survey was conducted by G. Gartrell and W. G. Elford (Adelaide, South Australia) during June 1969. A total of 13 meteors indicated an average radiant of α=289°, δ=-6° centered on June 11. Finally, during June 2 to July 2, 1969, Z. Sekanina directed the Radio Meteor Project at Havana, Illinois. Thirty-five meteors indicated a radiant of α=297.1°, δ=-7.1° when the shower reached maximum on June 17.5.
No convincing proof of this shower’s visual existence is present in any of the standard visual catalogs produced in the past.
The three established radar orbits are as follows:
| ω | Ω | i | q | e | a | |
|---|---|---|---|---|---|---|
| Nilsson | 328.9 | 84.3 | 40.1 | 0.113 | 0.93 | 1.613 |
| Gartrell Elford | 324 | 80 | 39.5 | 0.15 | 0.90 | 1.852 |
| Sekanina | 329.5 | 85.8 | 39.3 | 0.114 | 0.916 | 1.348 |
Gartrell and Elford suggested the stream might be related to comet 1618 II, the orbit of which follows:
| ω | Ω | i | q | e | a | |
|---|---|---|---|---|---|---|
| 1618 II | 287.4 | 80.3 | 37.2 | 0.390 | 1.0 | — |