SatSpy: Keeping an Eye on the Sky

A legacy of tracking the Heavens

Between 1995 and 2001, SatSpy was the name of a pioneering software that enabled amateur astronomers and professionals to track satellites as they crossed the night sky. It provided a graphical interface for the mathematical calculations that helped users predict orbital paths with remarkable accuracy. Though development ceased in 2001, SatSpy’s impact remained. It inspired enthusiasts to explore the complexities of satellite orbits, contributing to careers in astronomy, space policy, and engineering. Today, SatSpy.com is a gateway to the satellite watching hobby, the broader challenges of space sustainability and a software archive.

The Aspiring Space Traffic Manager's Handbook

How to spot satellites in the night Sky

What Makes a Satellite Visible?

Satellites become visible when they reflect sunlight toward the Earth. Unlike stars, which generate their own light, satellites are illuminated by the Sun, making them easiest to see shortly after sunset or before sunrise when the sky is dark, but the satellite is still catching sunlight. Read more...

Where to look in the sky

Satellites typically appear as small, bright dots moving steadily across the sky. They follow predictable paths, often traveling from west to east. Some, like the International Space Station (ISS), can be seen high above the horizon, while others may skim closer to the edges of your view. Checking satellite tracking websites or apps can help pinpoint the exact direction to look. Read more...

When are the best times to look?

The best times to spot satellites are during the hours just after sunset and just before sunrise when the sky is dark, but the satellite is still illuminated by the Sun. Mid-night passes are usually difficult to see because the satellite is in Earth’s shadow. Clear nights with minimal light pollution provide the best viewing conditions. Read more...

Which satellite?

There are thousands of satellites orbiting Earth, but a few are particularly easy to spot. The ISS is one of the brightest and most spectacular, visible even in city skies. Other notable satellites include Starlink trains, Iridium satellites (which used to produce bright flares), and various weather or spy satellites. Read more...

Essential tools

While many satellites can be seen with the naked eye, using basic tools can enhance your experience. A good satellite tracking app or website will help predict when and where to look. Binoculars can reveal more detail, and a red flashlight helps preserve night vision. A star chart or planetarium app can also be useful for identifying background stars. Read more...

Preparations

Find a location away from bright city lights for the best visibility. A wide, unobstructed view of the sky—such as a park, open field, or hilltop—helps spot satellites as they move across the horizon. Give your eyes time to adjust to the darkness, and dress warmly if you’re observing on a cool night. Read more...

Find that satellite!

Once you're in position, relax and scan the sky for moving points of light. Unlike airplanes, satellites do not blink or have red and green navigation lights. As the satellite moves across the sky, enjoy the thrill of spotting a human-made object orbiting high above Earth! Read more...

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