What crucial piece of information does the transit method *by itself* fail to provide about an exoplanet?

Answer

The planet's mass.

The transit method yields size (volume) through the dip depth and orbital properties through timing, but it does not directly measure the amount of material, which is mass.

What crucial piece of information does the transit method *by itself* fail to provide about an exoplanet?

#Videos

How to Detect EXOPLANETS - The Transit Method - YouTube

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