Double Stars Discovered by IOTA and Reported to JDSO

(Journal of Double Star Observations)

Tony George

Presented at IOTA 2013 Conference Toronto, Ontario, Canada

JDSO Reports Submitted October 2012 – July 2013Summary Table

JDSO Publish Date

Event Date Asteroid (No) Name

Target Star Separation (mas)

PA

Vol. 8 No. 4 Oct1, 2012

2009April 6

(336) Lacadiera

3UC197-115376 7.5 ± 0.9 124.9 ± 6.3

Vol. 9 No. 2April 1, 2013

2012March 11

(57) Mnemosyne

BN OrionisTYC 126-0781-1SAO 112952HD 245465

3.8 ± 0.8 63.6 ± 15.2

Vol. 9 No. 2April 1, 2013

2012August 12

(52) Europa TYC 6223-00442-1 37.8 ± ?.? ?.?

Vol. 9 No. 3July 1, 2013

2012December 3

(388) Charybdis

UCAC2 42913552 28.6 ± 0.6 110.2± 3.6

2009 April 16 (336) Lacadiera occults 3UC197-115375

Carl Bracken, Bob Cadmus , Al Carcich , John Centala , Robert Modic, Doug Slauson

The Lacadiera event found a fourth component of a previously known triple star system, making it a quadruple star system. This is an example of an ABAB event with very unequal star magnitudes. This was also the fist time that we used the UCAC3 catalog to report a double star. We used UCAC3 because it contained the other three components of the quadruple star system

Two chords showed a clear ‘step’ event in the data, while a third chord showed a partial occultation of only one of the two components – essentially a graze event with only one component occulted. This may be a first for IOTA observers.

BN Ori, an INSB eruptive variable. An A7 (Pre Main Sequence) star, 2-5 solar masses, with some surrounding gas and dust (faint emission nebula) and possessing an accretion disk. This report was of great interest to professional astronomers.

BN Orionis (TYC 126-0781-1) Duplicity Discovery from an asteroidal occultation by (57) Mnemosyne

John Brooks, Steve Conard, Joan Bixby Dunham, David W. Dunham, Robert Jones,

Thomas R. Lipka, Wayne Thomas, Wayne H. Warren Jr., Rick Wasson, Jan Wisniewski,

TYC 6223-00442-1 duplicity discovery from occultation by (52) Europa

A singe chord observation by Brazilian IOTA observer Breno Loureiro Giacchini, appears to be a BABA event.

UCAC2 42913552, a Double Star Discovered During an Asteroidal Occultation

Ricard Casas, Jorge Juan, Ramon Naves, Carles Perelló, Joan Rovira, Antoni Selva, Carles Schnabel,

Spain

Six observations carried out from Catalonia, Spain. This is a BABA event.

No Reports in progress

Conclusions

The discovery of double stars by asteroidal occultations continues to be an excellent method of finding or verifying double stars. Any time a light curve is obtained from a video record, it should be carefully examined for the presence of step events that could be due to duplicity of the target star.