- Navigator service
Navigator 4.5 (build 151) Service Pack 1 was released today.
This is a service release but there are some new features as well.
- fixed a problem in meridian calculation.
- fixed program crashes while printing from the star finder and
- Lunar calculation and distances between two objects (more
- Student table printer - This is a daily table of Equation of
time and declination for the Sun. It can be used to calculate
the meridian passage with just one table (more
- Star Finder - The polar chart may be centered in a celestial
sphere point. In older versions, the chart was always fixed to
- Star finder - Added a larger star catalog (Hipparcos 150) as
an option to the default 56 navigation catalog.
- Star finder - Added more color options.
Update is available for registered users of versions 4.0 and up
(CD-ROM and electronic versions).
If you did not receive the update notification via e-mail, apply
- Navigator 4.5 released
Navigator 4.5 was released today (aug/30/2004) with
many new and improved features. It includes new options, like dip
short for land navigation, sextant calibration table, parallax for
planets, more detailed refraction formula etc. The
celnav module interface was revised and reorganized to reflect the
celestial navigation workflow. I also added support for Windows
XP visual themes.
This is also a service release. Several small bugs
were fixed. I corrected a problem in the celestial engine, which
affects some stars at early dates. Read more about the problem
here. The upgrade is recommended
to all users. Read more details about the
All registered users of version 3.0 and up are entitled
to free upgrade (download). Apply to upgrade
A CD-ROM upgrade is also available ( CDROM version
users only. There is a US$10 shipping & handling charge ).
- Navigator "in the box" released
Navigator software for Windows is now available as
a packaged product. It includes the software CD-ROM and a 68 pages
illustrated booklet, packaged in a compact DVD type plastic box.
Very convenient to have on board. The product price is US$ 49.95.
The book includes a revised "celestial
navigation fundamentals" text and program usage instructions.
The software also received minor corrections and improvements
and the version number increased to 4.2 (the online version
will be upgraded soon)
The product is available online from Celestaire
Inc. Click here
- Yet another sextant: the
A few months ago I published a do-it-yourself octant
design (click here
to visit). This project was a lot of fun, but a lot of
work too. The results obtained from this instrument were quite good
and proved that an inkject printer (at least my hp-810c) can be
used to print a precision instrument scale.
But in the end I figured that it was too complicated
to appeal to the average 21 century busy person. So I went back
to the drawing board and designed the radically simple CD-Sextant,
a sextant build over a CD. Its small, easy to build and requires
only office tools.
Of course it has limited precision and is sometimes
difficult to trim, but can be used as a 1st sextant. I think it
can also be used in a number of science projects involving trigonometry
Click the link below to visit the CD-Sextant project:
Ok, ok. I promess I will put these silly toys away
and get back to code writing :-(
- The Navigator Store is
on the air
Surfing on the Internet, I found this interesting
company that sells, prints and delivers T-shirts, caps and a few
other things directly to the clients. You can create your own store
and upload the product designs. They take care of everything else.
So I went on to open my own "hardware"
The materials and work are of good quality.
I like the cap, which is very light and fresh.
Store address is www.cafeshops.com/nav
New Navigator version
I've been busy this year, working on a large financial
software project, and have not been able to put much time in the
Navigator project. But now summer is coming here in the south hemisphere
and I hear the call from high seas.
I'm working on the new version wish list, which
I will be publishing soon. Among the ideas are:
- Multiple LOP data entry grid. For productivity.
- Printed celestial navigation reports.
- Coriollis correction, for bubble sextants. Used
in air navigation.
- Dip short corrections. For lake navigation.
- Parallax correction for planets. This usually
small correction has been ignored in Navigator calculations...
- Calculation of angular distance between objects
in the star finder. This is good to check the sextant and build
- ..Sextant angle correction table. Not all sextants
are perfect, but they can be improved if the error is predictable
- Lunar calculation. Given 2 altitudes and a angular
distance, calculates the time and longitude.
If you want to suggest any feature or improvement
in Navigator software, it's just the right time. Just send me a
- New articles on the subject
For long time I wanted to know more about Macromedia
technology for building Internet movies. After playing with the
Flash 5 production software, I decided to do my first movie: a virtual
This is a pretty basic animation for those who never
handled a sextant. It shows how it works and what are the components
of this instrument, including arm movement, light rays and eyepiece
view. This small movie is called the
It was also incorporated it to the celestial
navigation fundamentals text.
||Then I went on to complete another
project I was planning for a long time: a homemade sextant.
I took sometime to write a program to print the sextant scale
using a ink jet printer. This was the missing part in my sextant
design. After this, I was able to complete the instrument in
one weekend, costing less then US$15 in materials. It took a
little longer to document the construction process, which
can be found in the X-tant
Enough of sextants for some time...
- Moon position calculations
improved - Navigator 4.1 released
When one compared the official "Nautical Almanac" pages
with the ones produced by the Navigator software for the
same period, the larger difference was certainly in the Moon GHA.
The Moon position is hard to predict because its orbit is very irregular.
The Navigator Moon GHA error was up to 0.7'.
This was OK for LOP calculations, since it resulted
in less than a mile error in the position (acceptable in celestial
navigation). But was way too high to perform the lunar
calculation. After some investigation, I was able to improve the
algorithm and reduce this error to 0.2', which is within the precision
of the best marine sextants.
On a more technical subject, I updated the UT to
TD (Universal Time to Dynamic Time) difference table to include
new precise predictions up to 2016 (with a good improvement over
the previously used prediction formula, at least up to that date).
The Moon results are so closer that I'm releasing
a minor version (4.1) with the new Moon calculations. I also updated
the services "The
Online Nautical Almanac" and "The
Navigator Star Finder", freely available
from this webserver (The shareware version 2.5 and DOS/HP 90LX version
1.3 have not been improved yet).
Another small change was the use of the label "IC"
(Index error Correction) instead of the previous "IE"
(Index Error). As a user pointed out well, this gives a better indication
of the sextant index signal input convention.
A few users reported a problem in the sextant altitude
input box. This problem is gone in this new version.
version 4.1 upgrade
Registered users of version 4.0 wishing to upgrade
may ask via email
(please inform registration email address and approximate date).
Navigator 4.0 is now available. This
new version has many new and improved features.
The star finder was improved, particularly the printed results.
> Now the star chart and table are printed in a single
sheet of paper.
> Boat course indication, for easy
> Improved celestial object identification in the chart
. Now all planets have their own icons, for easy identification.
The most visible stars (mag<3.0) are also indicated by a larger
> Checkbox do select/deselect LOPs, for Astronomical Position
calculation. Now you don't have to delete a LOP that is either wrong
or nearly parallel with other LOP. Just deselect it and recalculate
> Automatic LOP transport. In the prior versions, to calculate
a running fix, it was necessary to transport each LOP by hand. In
version 4.0, you can specify the boat course and speed; and the
LOPs will be automatically transported ( either to current time,
LOPs mean time or last LOP time ) when calculating the astronomical
position. This feature makes calculating running fixes as easy as
normal twilight positions.
> Implemented raster chart support. Now you can import popular
GIF or JPG image formats (for example, a scan of a paper chart).
You can use Mercator projections and even some satellite images.
Prior to use, images have to be imported, using ChartMaker program,
> Fixed chart viewer bumpy scrollbar behavior.
> Changed the help format from Windows .hlp to .html. The Help
system was revised.
> Improved the GPS interface
> Full printer support for vector and raster images.
Users that have registered in the last
12 months are entitled to free upgrade to this version. Please
contact the author via email for more information on upgrading.
If possible, send approximate date of registration.
Navigator 4.0 screen shot
- Navigator adopted by the Brazilian Navy School
I'm very happy to announce that the Navigator
was adopted by the Brazilian Navy School (Escola Naval da Marinha
do Brasil) for use in celestial navigation classes for junior officers.
The school licensed 30 copies of the program.
During the review process, navy officers suggested
several changes and clarifications in the Navigator, which
were implemented and are now incorporated in version 4. As a result,
the program is now much more usable - not only as a learning tool
- but as a day-to-day navigation tool. I´d
like to thank Captains Busnardo and Marcelo, for their help in Navigator
- Navigator web server now has accurate time keeping
Navigator web server (www.tecepe.com.br) have been running celestial
navigation applications for some time.
One of these is the Navigator Star Finder
This application is supposed to present the user with the current
GMT time, so he/she can view the current sky in any location, with
accurate celestial position data for the most visible celestial
But keeping the computer time was tricky. I would check it once
and a while, but the suggested time was frequently off the mark.
That has changed. I´m now using the program Dimension
4 to synchronize the computer clock with a reliable time sources
in the Internet. This program communicates periodicaly with these
time servers and adjusts the computer clock, which is not very reliable
in the long run, but performs well if adjusted frequently. Reference
time sources include the U.S. Naval Observatory and several universities
and research centers.
My server is now adjusted every 30 minutes. So the only time error
expected is the server response latency, which is normaly below
5 seconds. I highly recommend the program Dimension 4 for computer
time keeping. Check the programs web