North American Asteroidal Occultation Program

Updated 2020 Mar06


UTC Date and Time


Predictions Important IOTA Pages

Other Web Links


Steve Preston's Page

Derek Breit's Page

David Dunham's Page

Steve Messner's Page

Predictions of stellar occultations by

TNOs and Centaurs

Josselin Desmars



IOTA Main website

  North American Asteroidal Occultation Reports and Results

IOTA Lunar Occultations Page




Australia/New Zealand


Latin America


Worldwide Homepage





Miscellaneous Files Associated with Observations

European Observations of 20 May 2017 Centaur object occultation


IOTA's Eclipse Edge Determination Experiment 


Presentation to Riverside Telescope Makers Conference

David Dunham

Moberly Path (Solar Eclipse)

Erigone occults Regulus - 20 March 2014

David Dunham's Miss report from Bermuda

Kelly Beatty Summary for Sky and Telescope

Roger Venable Edit of David Dunham Venus Occultation

(4.4 Mb)

Alternate Video (mpg2)  (1.2 Mb)

IOTA Handout - mid-August 2017 Asteroidal Occultations

provided by David Dunham

  CYGNSS satellites (P. Maley)

2015 April 2  4:54 UT

Prediction Map

Orientation of 90 Antiope and Satellite from IMCCE

Orientation along Predicted Path

How To Observe the Argentina Occultation

By Steve Conard (Word document)

Venus occults lambda Aquarii - 16 April 2014

Animation of Event from behind Earth


Miscellaneous Files

D. Dunham's Mid-Atlantic Occultation Summary  

Quadea, the Incredible Shrinking Asteroid

presentation to APL Astronomy Club by David Dunham

IOTA Plans for the 2017 Total Solar Eclipse (PPT)

David Dunham

Solar Eclipse Google Map


Support for the ESO Large Programme

List of High Interest Asteroidal Occultations

(zipfile provided by Eric Frappa)




Downloads Miscellaneous Files Publications


Important:  KIWI-VTI Startup Procedures

by Dave Gault


The "Mighty-Mini" Videocamera System

by Scotty Degenhardt



PVC Video Camera Carrier

by Ted Blank


Timing Using CCD Drift Scanning

Drift Scan Description


The Effects of Optical Miniaturization on Occultations

by Scott Degenhardt (webpage)


My Metis Meteor  by Scott Degenhardt


Multi-Station Occultation Observing (7.5 Mb PP)

by Scotty Degenhardt


Scotty Degenhardt's Time Code

Procedures with the Canon ZR

( 850kb ZIP file)


How Scotty Degenhardt Sets Up Multiple Remote Stations

(16 kb ZIP file)


How to Download and Reduce Asteroid Occultation  DV Tapes

Richard Nolthenius


WWVB-based video time inserter

John Wright


JXD990-8000 Video Recorder Manual


"Maxi" Mount for use with 120mm refractor

(August 2013 update)


Spreadsheet to Determine D and R times from

Canon ZR Date Code (Excel)


How to Reduce Time-Stamped Videos - KIWI-VTI (Word)

How to Reduce Time-Stamped Videos - IOTA-VTI (Word)

(uses above Excel Form)


How To Basics. Using various Software programs.

Richard Nolthenius


Suggestions for Cold Weather Deployments (zipfile)


Video Camera and Focal Reducer Connections


Camera and focal reducer Hyades comparisons

(David and Joan Dunham)



The "Hercules" Club

Observers who have positioned themselves between the two shadows

of a double asteroid,

so as to observe an occultation by neither component.


IOTA YouTube Page

with many examples of previous events as well

Tutorials an using various software programs


An Occultation Observer Primer  (text file)


An Occultation Timing Primer Word  HTML


Introduction to Occultations (pdf)

Paul Maley, Richard Nugent


Occultations by Asteroid Satellites


Lunar Occultations of Comets  Word    Text


Chasing the Shadow:

The IOTA Occultation Observer's Manual



Powerpoint Presentation to

N. Virginia Astronomy Club

by David Dunham - April 13, 2008 ( 5 Mb)


Richard Nugent's Solar Eclipse Summary


----------  Minor Planet Bulletin articles  ----------

A Trio of Well-Observed Asteroidal

Occultations in 2008

Minor Planet Bulletin, 2009 July-Sept.

pp. 98-100


Occultations by 81 Terpsichore and 694 Ekard

in 2009 at Different Rotational Phase Angles

Minor Planet Bulletin, 2010 Oct-Dec

pp. 140-142


Several Well-Observed Asteroidal Occultations in 2010

Minor Planet Bulletin, 2011 Oct-Dec

pp. 200-204


Occultation Evidence for a satellite of the

Trojan asteroid 911 Agamemnon

Planetary and Space Science

Vol. 87, October 2013, pp. 78-84

Full text (as PDF download) available from

Cornell University Library


Asteroidal Occultation by 82 Alkmene and the

Inversion Model Match

Minor Planet Bulletin, 2015 Apr-Jun

pp. 129-131



----------  JDSO New Double Star articles  ----------

(select Archives)

Vol 6, No 2   1049 Feodosia

Vol 7, No 2   675 Ludmilla

Vol 7, No 3   790 Pretoria

Vol 7, No 3   160 Una

Vol. 8, No. 4   336 Lacadiera



Review of the 29 May Eudora Occultation

(by D. Dunham)


 Gravic Astronomy Workshop - Saturday, October 8th

(proposed agenda)

Summary of the Astronomy Workshop at Gravic



Basic Information on Occultations (Eclipses) and the

July 19, 2011 occultation by Antiope

David Dunham



North American Annular Eclipse, May 20, 2012

Richard Nugent






North American weather satellite image


Western North America weather satellite image


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