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Both calculators run independently — change the inputs on either side to compare results.

Planetary Transit Calculator

Estimate when inner planets Mercury and Venus will cross the disk of the Sun as seen from a specific location on Earth. Used by astronomers and educators to plan observations of these rare celestial events.

Observer Latitude (degrees)

Orbital Period (days)

Fill in the required fields to see your result.

Astronomy

Planet Visibility Calculator

Find the best times to observe Jupiter, Saturn, Mars, or Venus from your location. Enter your latitude and how many days you are from opposition to get a visibility score in degrees.

Observer Latitude (°)

Planet

Days from Opposition (days)

Fill in the required fields to see your result.

Key differences

	Planetary Transit Calculator	Planet Visibility Calculator
Category	Astronomy	Astronomy
Inputs required	2	3
Result	Next Transit in (days)	Maximum Altitude (°)
What it does	Estimate when inner planets Mercury and Venus will cross the disk of the Sun as seen from a specific location on Earth. Used by astronomers and educators to plan observations of these rare celestial events.	Find the best times to observe Jupiter, Saturn, Mars, or Venus from your location. Enter your latitude and how many days you are from opposition to get a visibility score in degrees.