Yes, you can photograph the brighter visible planets from a tripod, but your results will be very different from the Moon.

At 800mm, planets are much smaller in apparent size than the Moon, so they usually won’t fill much of the frame. Bright planets such as Venus, Mars, Jupiter, Saturn, and Mercury can be recorded, but most will look like small points or tiny discs. Jupiter may show a little detail, and Saturn may be recognizable, but don’t expect strong surface detail with a camera lens alone.

For best results, use a sky map app/site to locate planets, focus manually using magnified live view, and use tripod technique such as mirror lockup and a remote/cable release to reduce vibration. Cropping will likely be necessary.

If your goal is detailed planetary photography, an 800mm setup is generally not enough. Serious planet imaging usually uses much longer focal lengths—often telescopes around 2000–4000mm or more.

So: yes, it’s possible on a tripod, especially for bright planets, but realistic expectations are important: you’ll capture them, not get Moon-like closeups.