Planetarium V1.1

Planetarium_UserGuide_V1_1 Version 1.1 Planetarium v1.1

User Guide

http://www.corecoders.com/

If you have purchased Planetarium V1.0 or V1.1 for the iPhone 2G / 3G or iPod Touch / iPod Touch or iPod Touch 2nd Generation then Core Coders would like to thank you for your support and we hope that you enjoy your application.

I remember when I was at school we used to have a mechanical Planetarium and I was hypnotized by the planets and our moon going around the Sun. Years later I developed a very basic Planetarium for my ZX81 personal computer that was based on some pretty dubious calculations but it worked even though Earth was an “E” and the moon was an “M” not quite 3D but in those days 3D computing was only available to the very few.

Developing a Planetarium for the iPhone and iPod Touch would be a great way of getting a Planetarium to as many people as possible. One of the main design brief was to allow the user to take full control of the positioning to this end we developed a 6 degree of motion positioning system similar to a ﬂight simulator, in addition we did not really want to create a star map style application but rather one that allows the user to discover the Solar System in a extremely visual way.

The entire 3D model is powered by our custom CC3D library, this library was speciﬁcally written for OpenGL ES and has speciﬁc code to provide excellent performance on mobile devices running OpenGL ES V1.x or above. For more information about CC3D please contact core coders through our normal contact us form on our web site.

I would like to thank all the engineers, testers and customers who gave their time and advice in developing this application.

Thank you for purchasing Planetarium - you now own a Solar System in your pocket and we hope you enjoy using it as much as we have enjoyed developing this application.

We like to call this application a Planetarium simulation as there are some speciﬁc details that have been altered to improve the use and look of the application. However the positions of the planets and the moon are correct for the date and time selected.

First of all the planets are scaled up by 250x, moons scaled 500x, the Sun scaled by 25x and ﬁnally the all moon orbits are 20x there respective distances. If we did not do this it would be incredibly difﬁcult to move around the Solar System with touch gestures and it would make the whole program clumsy for the casual user.

The following parts of the simulation are however accurate1

1. Orbits are correctly displayed. 2. Ecliptic Plane is correctly calculated. 3. Equatorial Grid is correctly positioned. 4. Planet Axial Tilts are correct. 5. Planet Polar / Equatorial Radius ratios are correct. 6. Planet and Moon positions are correct. 7. Planet rotation period is correct. 8. Sun rotation period is correct. 9. Star positions and magnitudes are correct in Star mode. 10.Moon orbit speeds.

The following parts of the simulation are subject to some errors:

1. Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto bright facing side. 2. Orbital positions or moon (other than the moon) are subject to errors. (we are looking to improve this in the next version). 3. Planet and Moon textures have been processed to look slightly more colourful speciﬁcally for iPhone/iPod Touch screens.

Using the Planetarium has been designed speciﬁcally to make it easy with a touch screen interface.

Once you have installed the Planetarium you should see the icon below on your iPhone/ iPod Touch.

Simply touch the icon to launch the application and you should see the loading screen as below:

See Troubleshooting section if the application fails to load or execute correctly.

Note: Version 1.1 does take a little longer to load than the previous version and we are working to improve this on the next version.

© 2009 Core Coders Ltd, All rights reserved. Page 4 of 16 Planetarium_UserGuide_V1_1 Version 1.1 Once the application has loaded the simulation will start with the current date and time and set the “target” object to Earth.

The standard display shows the target object (if applicable) in the top left and the UTC date and time in the top right.

Please note: This application only displays UTC time as this is used for the astronomical calculations.

If you slide you ﬁnger across the screen then you will rotate you view around, if you tap the display without moving your ﬁnger you will get the options display:

© 2009 Core Coders Ltd, All rights reserved. Page 5 of 16 Planetarium_UserGuide_V1_1 Version 1.1 The options display allows you to select a target celestial object such as a planet or moon and travel to it, additionally there are a number of buttons to control time. You can also select the Setting tab to display the view settings.

The option display automatically fades away after 3 seconds unless the Setting tab is active. However if you select a target object the options display is hidden immediately.

Target and Selection Modes

The Planetarium has two modes of operation, these being Selected and Target. In selected mode the orbit of the selected celestial object will highlight in red (if orbits are shown see settings for more information). If you press the selection button again then the Planetarium will go into Target mode - in this mode your position will move and follow the new target object.

To get out of target mode simply drag your ﬁnger on the screen and the system will go back to selected mode.

Note:

When targeting objects the camera will smoothly rotate in all axis and this includes roll so occasionally you might ﬁnd the camera is upside down this is normal functionality for this style of positioning system. Simply use two ﬁngers to rotate around to the correct way.

Planet Target Controls

Planet target controls are shown at the top of the display, when you select a planet with moon targets then these will be display under the selected planet target control.

Description

Set Mercury as your selected/target object.

Set Venus as your selected/target object.

Set Earth as your selected/target object.

Set Mars as your selected/target object.

Set Jupiter as your selected/target object.

Set Saturn as your selected/target object.

Set Uranus as your selected/target object.

Set Neptune as your selected/target object.

Description

Set Pluto as your selected/target object.

Solar System Position

The solar system positioning provide a quick view of the of the solar system facing down.

Description

Move the position above the solar system at a position of 50AU facing towards the Sun.

Description

Slow down time and send it into reverse.

Stop time.

Set time to now.

Set time to real-time. Moving at normal pace.

Speed up forward time or slow down reverse.

Settings Panel

In addition to the Target and Time Controls you can set a number of view settings.

Control Description

Show Orbits Show or Hide Orbits.

Show Ecliptic Show or Hide the Ecliptic Plane Grid.

Control Description

Show Status Show or Hide the status display that shows the currently selected or targeted celestial object and UTC time display.

Equatorial Grid Show or Hide the Equatorial Grid/Sphere.

Disable Sleep Disable Sleep - when this is enabled the iPhone or iPod Touch will not go to sleep and the application will continue to run. This should only be enabled for devices connected to power

Control Description

Milkyway Milkyway Mode: Off - Black background.

Stars - 27,000 stars correctly position with the correct magnitude will be displayed.

Image - High Deﬁnition image of the Milkyway speciﬁc processed and positioned correctly will be displayed.

When moving around the Solar System without using the Target object requires you to use the Touch Gestures to control your view on the Solar System. The Planetarium uses an advanced six degrees of motion camera (similar to a ﬂight simulator cockpit display). The six degrees of motion are controlled as follows:

Guesture Description

Single Finger Drag Up/Down Rotates up or down. (Pitch)

Single Finger Drag Left/Right Rotates left or right. (Yaw)

Two Fingers Drag Rotate Rotates around clockwise or anti-clockwise (Roll)

Two Fingers Drag Up/Down Move Up/Down

Two Fingers Drag Left/Right Move Left/Right (Strafe)

Two Fingers Pinch / Zoom Move Backwards / Forwards

With a little practice it is possible to move around Planets and the Solar System with ease, if you get lost or are ﬁnding it difﬁcult turn on the Equatorial Grid and this will help you when learning the controls.

Description Notes

Planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto*.

Moons All major moons (>400km radius) Earth - Moon Jupiter - Io, Europa, Ganymede, Callisto Saturn - Titan, Rhea, Lapetus, Dione, Tethys, Enceladas, Mimas Uranus - Miranda, Ariel, Umbriel, Titania, Oberon Neptune - Triton Pluto - Charon

Orbit System Transparent, Blue (unselected) Red (selected/target) All planets and moon (earth) correct position. All other moons accurate orbit (position may have errors) On/Off

Ecliptic System Major markers 10Au (Approximately 80 light minutes) Minor markers 1Au (Approximately 8 light minutes) Transparent, Light Grey (Major Marker), Grey (Minor Markers) Grid On/Off

Status Panel Target / Selected celestial object. Date/Time in UTC yyyy mmm dd HH:MM:SS

Equatorial Grid/Sphere Right Ascension: 7.5° (15min) Minor Markers 90° (6hour) Major Markers Color: dark cyan Declination: 7.5° Minor Markers 1 @ 0° Major Marker Color: cyan On/Off

Disable Sleep On/Off

Background Modes Off: black background. Stars: 27,000 stars or magnitude -7.5 or greater. Brightness correctly calibrated for display but curve increased by 4x and 10/255 cutoff. Star positions correct to J2000. Image: High Deﬁnition image - with spectrum and detail updated. Correctly re-calibrated for accurate position.

Positioning System Full 6 degrees of freedom (ﬂight simulator mode) Forward/Back Strafe Left/Right Up/Down Roll, Yaw, Pitch Smooth camera mode: on

3D System 20-25fps on iPhone 3G/iPhone 2G/iPod Touch ﬁrst generation. 30-35fps on iPod Touch second generation. Modeling and scene processing by CC3D library.

* Planetarium lists Pluto as a planet for ease of use.

OK - we have worked hard to make this application as robust as possible but there are a number of occasions that something might go wrong.

Symptom Cause

Application will not start If the application fails even to display the loading screen then ﬁrst of all do the following: 1. Power off/on your device (hold power button).

If this does not ﬁx the problem then if you purchased this application on your PC/Mac iTunes then simply delete the application on the DEVICE and re-sync.

Application shows the This is likely due to a memory problem possibly an loading screen but then application that ran before has not correctly released crashes. memory. Re-boot your device and try again.

Time is not correct. Remember we are only displaying UTC.

Earth position not correct. Check you device time is correct for your timezone.

Other problems Please report then at http://www.corecorders.com

In developing this complex application we have come across a number or books, articles and information that might be of interest to other developers and users.

Books on Astronomy Calculations

We found these books an invaluable source of mathematical information for everything in astronomy.

Astronomical Formulae for Calculators - Jean Meeus Practical Astronomy with you Calculator - Peter Duffett-Smith

In addition we found further information at: http://www.clearskyinstitute.com/xephem/

Information and Examples of Texture Maps

James Hastings-Trew has some great textures that have been used to base some of the textures used in this program. http://planetpixelemporium.com/

Other textures and graphics available from the following sites. http://photojournal.jpl.nasa.gov/index.html http://maps.jpl.nasa.gov/ http://www.mmedia.is/~bjj/

For general space information

The JPL nasa site has an enormous amount of image and pictures some of which were used within this product. In addition JPL have a range of media and other information well worth a look. http://www.jpl.nasa.gov/

If you want further information wikipedia has an incredible amount of information, pictures, graphics and animations regarding all aspects of Space, Solar System and Planets.

Books on 3D Graphics

Finally if you are really interested in developing 3D graphics then I can recommend the following books - although you will need a good understanding basic mathematics for this.

Mobile 3D Graphics with OpenGL ES and M3G - K. Pulli, T. Aarnio, V. Miettinen, K. Roimela and J. Vaarala OpenGL ES 2.0 Programming Guide - A. Munshi, D. Ginsburg and D. Shreiner.

We are already working on the next version of the Planetarium and these updates will be free for those who have already purchased a copy of Planetarium, if you have any suggestions then please visit our web site at www.corecoders.com and goto the contact us link.

Thank you for your continued support

Core Coders Team.