Image 75 of 268
Trails of Flaring Geosats (October 2024)
Geosat Trails near Saturn in Aquarius (Oct 2024).jpg
This captures trails from geostationary satellites near Saturn in Aquarius and not long after local midnight, on October 2/3, 2024, with this area of sky just west of due south. At this time of year just past the equinox satellites in geostationary orbit can flare in bnightness for a few minutes as they reflect the Sun more than usual.
Indeed it was an extra naked -eye "star" near the line of three stars (Psi1, 2 and 3 Aqr) left of Saturn that drew my attention.
Realizing what was happening, I shot this series to record the satellite flares. The camera is tracking the stars from east to west, but the geostationary satellites, true to their name, stay more or less in the same spot in the sky relative to the horizon. So here, in tracked and stacked images, the stars remain pinpoints but the satellites streak, and change in brightness as they flare, as they are at left, near the point in the sky that was opposite the Sun when I shot these.
Most satellites are trailing parallel to the Celestial Equator which is above the main band of trails. But a few are moving slightly diagonally to that line.
These are not Starlinks. These are traditional communication satellites in geostationary orbits (the "Clarke Belt") some 35,700 km away, that stay over the same area of Earth because they take 24 hours to orbit the planet, matching Earth's rotation rate.
The field of view is about 30º by 20º. I shot this from southeast Arizona from a latitude of 32º North. The trails have gaps in them due to the one second interval between frames.
Technical:
This is a stack of 31 x 1-minute exposures, with the RF28-70mm lens at 70mm, at f/2.2 on the Canon R at ISO 1600. The images are stacked to add the content to reveal the trails and accumulate them, rather than subtract them out as would normally done in astrophotography.
Indeed it was an extra naked -eye "star" near the line of three stars (Psi1, 2 and 3 Aqr) left of Saturn that drew my attention.
Realizing what was happening, I shot this series to record the satellite flares. The camera is tracking the stars from east to west, but the geostationary satellites, true to their name, stay more or less in the same spot in the sky relative to the horizon. So here, in tracked and stacked images, the stars remain pinpoints but the satellites streak, and change in brightness as they flare, as they are at left, near the point in the sky that was opposite the Sun when I shot these.
Most satellites are trailing parallel to the Celestial Equator which is above the main band of trails. But a few are moving slightly diagonally to that line.
These are not Starlinks. These are traditional communication satellites in geostationary orbits (the "Clarke Belt") some 35,700 km away, that stay over the same area of Earth because they take 24 hours to orbit the planet, matching Earth's rotation rate.
The field of view is about 30º by 20º. I shot this from southeast Arizona from a latitude of 32º North. The trails have gaps in them due to the one second interval between frames.
Technical:
This is a stack of 31 x 1-minute exposures, with the RF28-70mm lens at 70mm, at f/2.2 on the Canon R at ISO 1600. The images are stacked to add the content to reveal the trails and accumulate them, rather than subtract them out as would normally done in astrophotography.
- Copyright
- © Alan Dyer/AmazingSky.com
- Image Size
- 6720x4470 / 16.7MB
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