Planetary Retrograde Tracker Screensaver
The Planetary Retrograde Tracker screensaver shows which planets are really retrograde right now. It is free, runs in your browser, and ESC exits.
How the Planetary Retrograde Tracker screensaver works
The saver computes each planet's real geocentric ecliptic longitude today and tomorrow.
A planet is marked retrograde when that real longitude is decreasing.
Each row also shows the planet's real current zodiac sign and degree.
Everything is computed locally — no network, no key.
A worked example
When Mercury's real longitude is moving backward through the zodiac, the board marks it RETROGRADE instead of DIRECT.
Settings & tips
- Retrograde motion is a real optical effect of relative orbital speeds.
- Accent recolours the retrograde badges.
- The Sun and Moon are never retrograde and are not listed.
Frequently asked questions
- Is retrograde motion real?
- Yes — it is a genuine apparent effect of Earth and another planet's relative orbital speeds, not folklore.
- How is it computed?
- By comparing each real planet's computed ecliptic longitude one day apart.
- Is a key needed?
- No. Everything is computed locally in your browser.
- Is it free?
- Yes — free, no download, in your browser.