The online orrery : ThePlanetsToday.com
App Controls Explained
For Non-Flash Users
If your browser does not support Adobe Flash, then we try and provide alternative content. This is often in the form of a video that shows the positions of the planets for the current year, or a Java App that shows the positions of the planets now with the ability to change the day by up to 30 days ahead or behind. For the Java App the positions of the planets are shown at 00:00 UTC on each day. We hope to expand the Java App in the future.
NOTE: Most of the controls described below are only for the flash version.
Feature: Storage of North South, Lat/Long and Background Brightness settings.
Due to requests from users, we have added the feature that the app will store the North/South and Lat/Long control settings so that everytime you use the site these settings remain constant. However in order to store this information you have to allow flash player to store information on your computer. If you do not wish to allow storage, then the animation will still function correctly, it's just that these control settings will not be stored.
You can allow storage by right clicking on flash animation and selecting "global settings", and then selecting "allow sites to store information on this computer" and then closing that dialog. And then right click on the animation again and select "settings" - and allowing theplanetstoday to store 10k (the minimum) of data on your computer. You can stop getting prompted to allow access by either selecting global settings - "Block all sites from storing information on this computer" and/or by selecting Settings - "Never Ask Again".
Lunar Phase Display
The phase display shows the phase of the moon - or any planet of the solar system. By clicking on the moon, a dialogue appears which allows you to select any of the planets of the solar system. You can close the dialogue by clicking on the phase display again.
Selecting the outer planets is normally very dull because they are nearly always in the full state - we always see the sunny side of these objects. Selecting the inner planets is more interesting, but only slightly though.
In order to control the application you need to open the control panel by clicking on the control panel release button. Once you're happy with the settings you can close the control panel by clicking on the control panel close button.
The upper part of the control panel controls the time time at which you are seeing the planets. By default the planets are shown in real time (time shown in your local time with daylight saving).
You can switch on or off your local time adjustment by clicking the "local" button. This doesn't change the position of the planets - just the way the time is displayed. Without your local adjustment the time will be the time in UTC (Coordinated Universal Time) which is basically the time at Greenwich, London.
By clicking the "+DST" button you can also show or remove your daylight savings adjustment. Note: If you are going to look at the planets at various times in history, or in the future, then you may have to know whether DST should be on or off. DST only began in 1916 and has been adopted in different nations at different times. This application does not contain any historic data for DST and only knows whether it is in action now.
By clicking on the yellow button, application time is returned to the default which is the real time now.
The slider control allows you to speed up or reverse how fast time changes. The slider has two knobs - the top is a coarse control so that you can speed up and slow down time by large amounts. The bottom knob is a fine control so that you can tweak how fast time changes. To the left is a + or - indicator to show if time is going forwards or backwards and a magnitude indicator to show how much faster than real time the time is changing. Up and down arrows allow the speed of time to be tweaked up and down - except in the following case.
When the coarse and fine sliders are both at maximum then clicking on the up arrow makes time jump forwards by 10 years, and double clicking jumps forwards by 100 years. When the coarse and fine sliders are both at minimum then clicking on the down arrow makes time jump backwards by 10 years, and double clicking jumps backwards by 100 years.
By clicking on the yellow button, the time speed is set to the default which is real time - i.e. 1 second per second.
The next three sliders control the display of the orbits; The first controls the brightness of the orbit trails, the second zooms in and out, and the third controls how "real" the orbits are.
By sliding the orbit realism control to the left (to the eye symbol) it allows you to see all the orbits laid out in neat, equally spaced, circular rings. This is not at all accurate since orbits are elliptical and not regularly spaced. By sliding the control to the right (tick symbol) the orbits are shown as they really are. This means that it is difficult to see all the planets because if you zoom out to see the outer planets, the inner planets, which are very close to each other and the sun, jumble together.
If you wish to see where all the planets are in their orbits relative to the sun, put the control nearer the eye symbol, if you want an accurate view - and especially if you want to know which constellations the planets are in when viewed from earth, put the control to the tick symbol.
Orbit controls are removed from the Geocentric view since all planets are always shown at the same distance from earth.
There are 2 planet display control sliders. One controls the size of the planets (magnifiers) and the other their relative sizes (eye/tick). By sliding the slider to the tick, all the planets are shown in the correct size relative to each other. By sliding to the eye (the default view) the planets are not shown in their correct proportions, but are easy to see. The size slider allows you to choose how large you'd like to see the planets. With the slider set to minimum, the planets (although mostly invisible on the screen) are still much larger than their true size when compared to the scale of the orbits.
The sun is never shown to scale with the planets simply because in most meaningful circumstances it would not fit on your computer screen.
The next slider controls the zodiac display brightness. It also controls the brightness of the planet "retrograde glow" indicators.
The next slider controls how bright the planet labels are shown.
The next three items allow control over how we view the solar system.
The first drop down control allows you to specify which solar system object remains stationary. The sun (Sol) is usually the default setting. If you select the earth as the stationary object (and perhaps dim the orbits to be invisible) you can see that the other planets wobble about in an almost alarming manner. This is why the ancient greeks called them "asteres planetai" which means "wandering stars", and why we now simply call them planets.The cross hair control pulls which ever object selected in the previous control into the centre of the screen. Very useful if you've zoomed in and then got lost.
The final N/S control allows you to flip from seeing a view of the solar system from over the earths north pole (the default) to seeing a view from over the earths south pole. Which ever view you use, the north pole of the earth is leaning towards the top of the screen. If your flash settings allow us to store data on your computer, then the state of the N/S is stored between sessions.
You can also drag the display about by normal click and drag options.
3D On/Off Control
The 2D-3D button is provided in some views.
When activated it alters the display by putting each planet on a "stalk". The length of the stalk indicates the distance the planet is above or below the plane of the ecliptic. For many planets the distance is very small and not noticeable unless one zooms in on them. For other objects - like the dwarf planets and comets the distance can be very large indeed.
The length of the stalk is also controlled by the Orbit Realism Slider Control - so the stalk length will only be 100% correct when the slider is in the "realistic" (tick) position. We've tried to indicate this connection by changing the look of the 3D on/off button depending on the position of the Orbit Realism Control.
When enabled, the view given is not really 3D, but rather a 2D view with 3D information included.
Dwarf Planet On/Off Control
If this button appears then it allows dwarf planets and their orbits to be included or removed from the display.
Background Brightness Button
The background colour can be changed from dark to light using the background brightness button.
A bright background can also be useful when trying to use the App on a mobile/tablet.
Where on Earth am I?
The final controls allow you to set a position on the earth using the lat (latitude) and long (longitude) sliders. A small marker on the earth shows the position you specify so that one can see where that location is in reference to the cosmos. If you're not sure of your current lat long, why not visit this NASA Data site where you can use the map to find your location.
The lower slider allows you to change the brightness of the horizon indicator. This indicator divides the screen into solar system objects (lying in the plane of the ecliptic) that can be seen from the lat/long position specified, and which are hidden from view because they are below the horizon. If the sun is visible then the sky is shown blue.
If your flash settings allow us to store data on your computer, then the state of the long lat controls are between sessions.
Where in the sky are the planets?
Set the position to your current lat and long and move the slider to show the artifical horizon.
By looking at the horizon, you can get an approximate idea where the planets are right now in the sky. If the planets are shown near the artificial horizon, then they'll be in the sky near the east or west horizon. If the planets are higher up, then they'll be found more toward the middle of the sky. All the planets (but not dwarf planets) lie in the same path that the sun takes so as long as you take note of how the sun passes through the sky during the day, then you can look for the planets along a similar line during the night. It depends where you are in the world but if the Sun rises high at mid day then a planet opposite the sun will be low in the sky at midnight. If the Sun only rises low then the planets will rise higher. With a little thought and practice it should become reasonably easy to translate from the view shown by this website to where the planets are in the sky.
You wont be able to see the dwarf planets - they all need good (or extremely good) telescopes to be seen - and because they do not orbit in the same plane as most of the main planets, they can appear higher or lower in the sky than you may expect from looking at our plan view of the solar system.
The display is all over the place!
If you find that after playing with the controls you get lost, then simply hit all the yellow buttons and the screen will return to the default settings.
How Accurate is it?
Although the app is quite accurate, it is not perfect and should not be used for detailed astrology predictions, sunrise, sunset times or anything else which requires close accuracy. The aim of the project was to provide an accurate view of the solar system which will inform and raise interest in all things Astrological/Astronomical but not provide a nanosecond/nano degree perfect astronomical display for all time.
The data from NASA covering comets and dwarf planets often only covers the period from 1600 AD to 2200 AD. Therefore positions outside that time are estimated.The least accurate object is the moon. It has a very changeable orbit and a fast motion across the sky and so may be a few degrees out from time to time. However, planets should be within a degree or so of their exact position at any time.
However, if more people find it interesting then the app accuracy could be improved...