When Bifrost Bridge is opened, it's visible and it is Cylindrical with a huge radius to accept multiple people. I have never seen someone calling Heimdall to beam up these and these people. They all just stand nearby.
Can I jump near Thor (in Bifrost radius) to visit Asgard when Bifrost is opened? Or, can I throw a Nuclear Weapon inside Bifrost radius in order to attack Asgard?