Asteroidal Occultation Maps for North America: How It's Done

Occultation Maps for North America

How It's Done

Map Index
Compatibility Issues Time Conversions
How It's Done Change Log
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I was inspired to undertake this project by the great work Kiwi Geoff has done in figuring out how to use the Google Maps API and in writing Shadow which has made it so easy to get data out of Steve Preston's Asteroidal Occultation Predictions pages and onto maps.

I hope to keep producing these maps as the data becomes available on Steve's site, but am making no promises.

Charlie Ridgway


Task Orbital Motion Program Orbital Elements Generate Source File Parse Data Create Map
Tool Occult Occultmnt for Occult Asteroidal
Shadow Google Maps API
Written By Dave Herald Steve Preston Steve Preston Kiwi Geoff Google
Task Performed By Steve Preston Steve Preston Steve Preston Charlie Ridgway Charlie Ridgway

These pages are the result of a lot of work by other people. All I do is take the end product of that workflow and package it in some HTML for you to see.

Dave Herald
First there is Dave Herald. He writes software down under in Australia. His contribution was the writing of a program called Occult that is used to predict occultations.
Steve Preston
In the middle, Steve Preston uses the Occultmnt file he writes and the Occult program to identify and document the circumstances of asteroidal occultations, which he publishes on his Asteroidal Occultations Predictions web page.
"Kiwi Geoff"
Then comes "Kiwi Geoff" who wrote a great little program called Shadow that takes either the output from Occult of one of Steve's web pages and converts it to data points that can be used in around a dozen mapping applications and in GPS receivers. Kiwi figured out how to use the Google Maps API to plot asteroidal occultations and wrote some JavaScript functions to add additional functionality to the maps. As his name implies, Geoff is also down under, but on the smaller island of South Island, enzed (New Zealand).

All I do is identify occultations that will be visible from North America on Steve's site and download the details of the event. I use Kiwi Geoff's Shadow program to extract the relevant data elements from that file in a format that is compatible with Google Maps. Then I past that data into my web page template, which contains the Google JavaScript and other relevant information to make the maps work, and customize the page for that occultation. Since Shadow creates a file for use with Google Earth I Zip that up and include a link to it at no additional charge. On a good day it takes less than 10 minutes to create a map.

Where It's Been Mentioned (its in Spanish)
15Sep05Google Earth Blog
26Aug05Ogle Earth
26Aug05Google Maps Mania

Where It's Been Viewed

World Map

Put your dot on this site's

Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 2.5 License.