Occultation observations from around the world

July 2012 to Sept 2013

Dave Herald

Part 1

Lunar OccultationsSummary of observations

July 2012 – Sept. 2013

# Observations by region

• Nth America 458• Australasia 1140• Japan 4158• Europe 1451• MiddleEast 25

Double star observations

• WDS stars measured 78• Discoveries 22• OCC stars +’ve measures 7• Wide doubles (>2”) 8• OCC stars NOT double 99• WDS observed as single 24• Doubtful 16

TOTAL 254

Reports collected and analysed by Brian Loader, New Zealand

Part 2

Asteroidal OccultationsSummary of the best events

Jul 2012 – Sept 2013

The number of events is falling....

Number of successful events by region, and max # sites: 2012/07 2013/08

• Australasia23 + 41 (11 sites)• Europe 32 + 33 (34 sites)• Japan 7 + 14 (14 sites)• US 27 + 50 (11 sites)

Japan has a much smaller land area than the other regions;Australasia has a much smaller population

Satellite discoveries#1 Agamemnom – 2012 Jan 19

Satellite discovery #2 Viipuri – 2013 Aug 3(?? - single integrated frame event)

Double stars discovered in asteroidal occultations

• New double stars can be discovered in an asteroidal occultation

• Separations are usually in the range 0.1” to 0.001”

• If several observers, the uncertainty in separation can be less than 1 milli-arcsecond

7 double stars discovered since June 2012

Star number Sep (mas) P.A. Date Asteroid

6223-00442-1 37.8 -69.8 2012 Aug 12 52 Europa

HIP104465 9.2 ± 0.8 171.5 ± 1.2 2012 Nov 25 168 Sibylla

2U42913552 28.2 ± 0.5 107.6 ± 3.6 2012 Dec 3 388 Charybdis

2U46691743 43.0 ± 0.6 237.0 ± 1.2 2013 Jan 27 536 Merapi

1950-00148-1 28.3 ± 0.4 12.3 ± 0.8 2013 Feb 6 92 Undina

6258-00144-2 1.0 -4.0 2013 Jul 24 1271 Isergina

2U30429828 380.0 240.0 2013 Aug 15 611 Valeria

Valeria - 2013 Aug 15 Wide double star (380mas)

Time diff: 66 secs

The 9 best results for the period

430 Hubris 2012 Aug 14, Europe

Pluto2012 Aug 6, Australia

521 Brixia2012 Oct 22, USA

87 Sylvia2013 Jan 6, Europe

45 Eugenia2013 May 20, USA

576 Emanuela2013 July 26, Australia

387 Aquitania2013 Jul 26, USA

489 Comacina2013 Aug 24, USA

139 Juewa2013 Aug 31, Australia

Any questions?