ISS Real-Time Tracker User Guide

User Guide


Tap an item from the list below to jump to that section:

Pass Predictions

Real-Time Tracking

Landsat 8 Imagery

Current Crew

Streaming Video


Pass Predictions

Tapping the telescope icon at the bottom of the main screen starts the process of computing up-coming visible ISS passes. First, ISS Real-Time Tracker gets your current location's coordinates. Then, it computes the visible passes for that location. The default number of days to predict passes is set in Settings. The passes are listed in chronological order along with detailed viewing data.

Data for each pass includes:

  • Date of the pass
  • Rating (0, 1, 2, or 3 stars)
  • Visible duration (in minutes and seconds)
  • Max visual magnitude (using same scale as astronomical brightness, i.e., apparent magnitude)
  • Time, azimuth, elevation, and compass direction for the start time, max elevation time, and end time

Each pass is rated based on its maximum magnitude (i.e., brightness). With the brightest passes gettiing the highest reatings. Passes are rated with 0, 1, 2, or 3 stars corresponding to fair, good, better, best. Passes rated at least fair, are highlighted with a green background in the date field.

Adding a Pass Event to Your Calendar

Tap any pass in the table to add it as an event in your calendar. When adding a pass to your calendar, two alerts will be set: the first for 1 hour before and the second for 20 minutes before the start of the pass. The starting and ending times for the pass are saved in the event in your calendar, along with the maximum magnitude, as well as the starting, maximum, and ending azimuths and elevations for the pass.

Change Number of Days to Compute & Refresh

Tap the Calendar icon at the top-right of the screen to change the number of days to compute and refresh the list. To change the number of days so that the app remembers your setting for next time, change it in Settings.


Pull down the table to refresh the data.

  • The pass predictions become less certain the further out in time they go.
  • Overhead passes returned are only those visible from your location for at least 300 seconds (5 minutes) and where the ISS is illuminated by the Sun.
  • If there are buildings, trees, or other obstructions, and depending upon the weather and other viewing conditions, you may not be able to spot the station.
  • You must give ISS Real-Time Tracker access to your location. When asked, tap OK.; You can change this permission in your device's Settings app.
  • Calendar events are saved in your default calendar.

Tap ⟵ to return to the map and resume tracking.

Tracking the ISS

To locate and track the International Space Station in real time, tap the play button at the bottom of the screen. To pause tracking, tap the pause button.

You can select from the following map types in Settings:

  • Standard (shows names, roads, and borders)
  • Satellite (shows terrain only)
  • Hybrid (the default setting: shows borders, names, roads, and terrain)

To zoom in or out of the map, use the slider control at the top of the map. This changes the scale of the map, which is displayed in degrees to the right of the zoom slider.

You can set the map scale range in Settings to any of the following ranges (in degrees):

  • Fine: 0.10° - 3.00° (0.15° - 3.00° for iPad)
  • Small: 0.33° - 10.00°
  • Medium: 1.00° - 30.00° (the default setting)
  • Large: 3.00° - 90.00°

There are three styles of markers, which you can select in Settings:

  • ISS icon (the default setting)
  • Circular
  • Small +

The time interval between map updates is automatically set from 1 to 6 seconds, based upon the zoom slider setting. With the slider all the way to the left, the update interval is set at 1 second. As you drag the slider right, it increases by 1 second up to a maximum interval of 6 seconds. This keeps the relative motion of the map roughly equal at all scales within a given range.

Copy Info to the Clipboard

Tap the copy button next to the info box on bottom of the map to copy the ISS's location, altitude, velocity, and associated time to the clipboard. You can then paste the data in another app.

  • If the Information box overlay setting is turned off in Settings, the copy button will not be available.
  • The music soundtrack will be disabled (not play) by default. Click the ♪ icon at the upper-right to toggle the soundtrack on/off.

Landsat 8 Imagery Help

This function displays a NASA Landsat 8 image at the current map coordinates, if available. The image covers an area determined by the Img Scale selector in Settings. The coordinates, date and time the Landsat 8 image was captured (see notes) are displayed above the image, along with the scale in degrees and percentage of cloud cover. Tracking will be paused while the Landsat 8 image is being downloaded. This allows you to view the Landsat image and then return to the map and compare the two views.

Change Image Scale

To change the image scale, tap the scale button on the upper-right. To change the image scale so that the app remembers your setting for next time, change it in Settings.

Save Landsat 8 Image in Photos

Tap the image to save it to your photo library.

  • If the ISS is over open ocean, or if Landsat 8 imagery is not available for the current map coordinates, no image will be displayed.
  • To display images with high cloud cover, turn this on in Settings. Otherwise, if ISS Real-Time Tracker determines that the image has more than 80% cloud cover, it will not be displayed.
  • The captured date refers to the date in which the image was captured by the satellite and saved in the NASA database. The image can be two or more years old.
  • You must give ISS Real-Time Tracker access to your photos to save an image. When asked to grant this permission, tap OK. You can change this permission in your Settings app.

Tap ⟵ to return to the map. Tap the Play button to resume tracking.


Tap the space suit button at the bottom of the screen to get a table of information about the current ISS crew.

Crew Bios & Tweets

Tap any cell in the table to pop-up the detail view for that crew member. This will display a brief bio. To view a full bio, tap the button on the bottom-left.

To visit the crew member's Twitter feed, open their Twitter profile by tapping the Twitter button. If you do not have the Twitter app installed, it will open in Safari instead. If the crew member does not have a Twitter profile, the Twitter button will not be displayed. Return to ISS Real-Time Tracker by tapping "◀︎ ISS Tracker" on the top-left of Twitter.

Tap X to close the pop-up and return to the crew table.

Copy Crew Data to the Clipboard

Tap the copy icon at the top-right of the screen to copy the crew names, titles, and nationalities to the clipboard. You can then paste them in another app.


Pull down the table to refresh the data.

Tap ⟵ icon to return to the map and resume tracking.

Streaming Video

The streaming video feature replaces the live video of Earth, which I removed when the HDEV Experiment reached its end-of-life in the Summer of 2019. NASA has replaced this video feed with previously recorded video. So, that's what this feature provides.

  • The video will often sequence through different views.
  • If your screen is blank, then NASA is not currently streaming any video. Just try again later.

Tap ⟵ to return to the map.


All of your current user settings are automatically saved on your device when you exit the app or switch to another app. This also includes the current zoom slider position. Each time you run ISS Real-Time Tracker, your settings are restored.

Tapping the ⟳ button on the Settings title bar, will clear all your user settings and change them back to their defaults. The zoom slider will reset to its default (center) position and What's New and other messages will be restored.

Tap ⟵ to return to the tracking view.

© 2016-2019 Michael Stebel Consulting, LLC
All rights reserved

ISS Real-Time Tracker is a DBA
Michael Stebel Consulting, LLC

© 2016-2019 Michael Stebel Consulting, LLC. All Rights Reserved.