The International Occultation Timing Association


Information Site for Lunar Occultations & Grazes

Last Updated 17 JUNE 2024
WARNING! Information and e-mail addresses contained herein, are for scientific use only. By entering this site, you agree that you will use this data only for lawful purposes and that, under no circumstances will you use this data to: allow, enable, or otherwise support the transmission of mass unsolicited, commercial advertising or solicitations via direct mail, electronic mail, or by telephone.


  • We encourage, promote and facilitate the observation of occultations and eclipses
  • We provide predictions for grazing occultations of stars by the Moon
    and predictions for occultations of stars by asteroids and planets
  • We also provide information on observing equipment and techniques,
    and we report to our members about observations made

  • To promote scientific research and discovery using occultation related methods
  • To conduct research at the local, regional and international level
    and to publish results of studies in popular and scientific journals
  • To stimulate public awareness of astronomical phenomena such as (but not limited to) solar and lunar eclipses and occultations of stars by minor planets, the Moon, and other solar system bodies
  • To improve lunar profile data through timing of grazing and total occultations
  • To determine shapes and sizes of minor planets and comets through timing of occultations of stars by these objects
  • To discover evidence of new, and confirm characteristics of previously discovered, satellites/companions of minor planets

The Value of Lunar Occultation Timings and Observations (D Dunham, D Herald, M Soma)

The Value of Graze Occultation Timings and Observations (Mitsuru Soma - YouTube Video)

Worldwide Upcoming Bright Star Occultation Events

Observers are encouraged to download the Occult software
to generate predictions for their areas, of fainter occultations

Check "Regional Information on Events" below for more information on occultation/graze events for local circumstances

How to read the country codes and prediction format

23 Jun - Occultation of Ceres - 7.5m - e Canada, central & e USA, ne Mexico, Caribbeans
27 Jun - Occultation of Saturn - 1.1m - e Australia, New Zealand
28 Jun - Occultation of Neptune - 7.9m - nw South America
11 Jul - Occultation of β Vir - 3.6m - w Africa, ne South America
14 Jul - Occultation of α Vir - 1.0m - USA, Canada
17 Jul - Occultation of α Sco - 1.1m - s Africa, Madagascar
20 Jul - Occultation of τ Sag - 3.3m - e Australia, n New Zealand
24 Jul - Occultation of Saturn - 0.9m - se Asia
29 Jul - Occultation of η Tau - 2.9m - Indonesia
29 Jul - Occultation of 27 Tau - 3.6m - se Asia
29 Jul - Occultation of 17 Tau - 3.7m - Indonesia, w Australia
29 Jul - Occultation of 20 Tau - 3.9m - Indonesia, w Australia
10 Aug - Occultation of α Vir - 1.0m - e Asia, Indonesia
14 Aug - Occultation of σ Sco - 2.9m - s South America
16 Aug - Occultation of τ Sag - 3.3m - s Africa, Madagascar
21 Aug - Occultation of Saturn - 0.7m - n South America, w Africa, Europe
26 Aug - Occultation of 27 Tau - 3.6m - nw Africa, e Europe
26 Aug - Occultation of 17 Tau - 3.7m - central Africa, Middle East
26 Aug - Occultation of 20 Tau - 3.9m - central Africa
26 Aug - Occultation of η Tau - 2.9m - n central Africa
27 Aug - Occultation of β Tau - 1.7m - Indonesia, nw Australia
29 Aug - Occultation of ι Gem - 3.8m - e Australia
06 Sep - Occultation of α Vir - 1.0m - w central Africa; ne USA, e Canada

2024 Predictions

Concerning 2023 IOTA Predictions Must Read(pdf format)
Concerning 2024 IOTA Predictions Must Read(pdf format)
2024 Worldwide Total Occultations of Bright Stars
2024 Occultation of Planets by the Moon
2024 Total Occultations of Bright Stars for 40 North American Cities
2024 North America Graze Tables and Maps - D. Dunham
Eclipse Maps and Weather

Asteroid Occultation Information

Steve Preston's World Wide Prediction Site
Derek Breit's Regional Asteroid Path Maps for USA
North American Asteroidal Reference Homepage
Asteroidal Occultation Results for North America
Worldwide Results Home Page
Report Form For Asteroid Observations
Japanese Astroidal Prediction Site (Japanese)
Japanese Astroidal Results (English)

Lunar Impacts and IOTA

NASA/Marshall main lunar impacts Web site
B. Cudnik's ALPO lunar meteor impacts Web site
D. Dunham's Impact Page (historical, 1999 & 2001, & earlier efforts)

Helpful Information

I.O.T.A.'s Primary Site
I.O.T.A. Membership Application - Discussion Maillist
"Chasing the Shadow: The IOTA Occultation Observer's Manual
The Occultation Observer's Handbook by Robinson & Povenmire
NWS Current Weather & Forecasts
Time Conversion Tables - UTC to Local for USA
World Time Zone Map
IOTA Annual Meeting Minutes

Occult Software and Related Information

Occult Prediction Software
Tips for using Occult by David Dunham (pdf file)
Lunar Report Generator
Occult/IOTA - Discussion Maillist
How to Use Occult 4 to Predict Comet Occultations
The ZC Star Catalog (not to be interfaced with Occult)
Expanded Site Files (updated file on 06 Jul 2024)

OccultWatcher Software

Basics of Total Occultations

Basic Information and How to Obtain Predictions
BeeperSync - An Alternative WWV Internet Based Timing Source
How to Report Observations
The Prediction Format for Total Occultations - [pdf format]
The Value of Total Lunar Occultations
Timing & Location Accuracies for Observations

Basics of Grazing Occultations

The Grazing Occultation
IOTA Standard Stations
North American city coordinates
Archive of Observed Graze Profile Reductions

Regional Information on Events - (external links)

Mid-Atlantic Occultations - D. Dunham
Kansas-Missouri Area - R. Sandy
Upper Midwest- MN, IA, ND, SD and WI
San Francisco Bay Area - D. Breit
Arizona and Surrounding Area - D. Dunham
Central America/South America (in Spanish)
Brazil by Breno Loureiro Giacchini (in Portuguese)

If you have a local URL for your area, send information to the webmaster for inclusion

Use of Video on Timing Events

A Light Weight Portable Video Setup - by R. Nugent
Richard Nugent's System - by D. Dunham
Tom Heisey's Video Setup (PDF)
"Millisecond Video Timing for the Masses" by S. Herchak
Finding Limiting Mag for Visual/Video Camera Observations

KIWI-OSD and IOTA-VTI Time Inserters

LiMovie measurement tool for video occultations (the most stable version)

Miscellaneous Stuff
I.O.T.A. Tax Information/Expense Report [pdf format]
Additional Reference Reading Material


astronomy and space links, shortcuts, favorites and bookmarks.

This site maintained for IOTA by Rob Robinson, Bonner Springs KS
Send comments and mail to Webmaster
Send comments and mail to I.O.T.A. President, Steve Preston
IOTA Administration, email I.O.T.A.

You are visitor number

shopify analytics ecommerce tracking

Since January 1997

Go to the Robinson Lunar Observatory