The ISS (International Space Station), completing one orbit around the earth every 92 minutes, approximately.
This application places the ISS on the map in real time.
Calculate the orbit from the current time of device and TLE data, which obtained www.celestrak.com.
Green line is drawn 50 minutes before and after the current position of the ISS.
The user's position is marked with an android with the arm held high, surrounded by a semi-transparent red circle.
The red circle indicates approximately the area where the ISS would be visible by the user. That is, if the ISS is inside the circle, in theory, you could watch it at the sky. Remember, NEVER LOOK DIRECTLY AT THE SUN!
Internet access is used to obtain maps and update once a day TLE data. More zoom means more data traffic.
From the preferences menu you can enable/disable automatic tracking on the map.
The local time Can also be superimposed on the map.
Although you can get to see the ISS for the day is much easier to see at night, because in the night sky is the second brightest object after the Moon and before of Venus.
But to be visible at night must be some circumstances:
-The ISS must be illuminated by the sun, ie outside the cone of shadow of the Earth.
-The sun must be at least 10 degrees below the horizon or, in other words, must have had at least 40 minutes before or must miss more than 40 minutes to come out.
-In its pass, the ISS must rise more than 5 degrees above the horizon. Less than 5 degrees is not visible by the distortion generated by the atmosphere.
From the main application window, pressing the menu key you can select "Visible Pass".
From this screen we have the date, time and position of the observer and a refresh button (circular arrow).
Pressing the button proceed to calculate the visible pass for the next 2 days (changeable in preferences screen).
The result is a list of steps visible. Each step consists of:
-Day and month.
-Initial instant. Time, altitude in degrees, azimuth in degrees (cardinal point equivalent)
-Instant of Maximum altitude. Time, altitude in degrees, azimuth in degrees (cardinal point equivalent)
-Final instant. Time, altitude in degrees, azimuth in degrees (cardinal point equivalent)
Alarms: You can on/off pressing alarm button (top-left icon).
The locator uses accelerometer, the compass of the device and the calculated data to show the position of the ISS on sky from observer's position.
That is, when we moves the device to the sky shows a red triangle in the position of the ISS and a green dotted line showing the visible pass.
It also includes a positioning aid, based vibration:
- Hold the device pointing to the horizon, turn on your feet so as to vary only the azimuth (N, NE, E, SE, S, SW, W, NW). When the azimuth differs from the ISS in less than 10 ° there is a vibration.
- Now vary the altitude, vibration intensifies as it approaches the ISS and will be greatest when the red triangle is displayed.
- You can activate / deactivate the vibration by touching the screen.
Altitude: The angle of a celestial object measured upward from the horizon of the observer. An object on the horizon has altitude 0 ° while one directly overhead the observer is 90 °.
Azimuth: The direction of celestial object measured along the direction of clockwise from the northern horizon of the observer. An object in the north has azimuth 0 °, east 90 °, south 180 ° and 270 ° west
If you like the app you can donate to developer from Extensions menu.