Please helpWhat additional info does the sidebar provide?

The sidebar tells us what Earth scientists are actually doing about the risk of an asteroid impact.

Explanation:

The main part of the page discusses how frequently the moon is hit by rocks;  how most rocks are too small to make it past Earth's atmosphere; how the rocks that do make it all the way to Earth's surface are usually pretty small and don't hit anything important; how screwed we would be if a massive rock – like an asteroid – made it to Earth's surface.

The sidebar says that scientists are understandably worried enough about these asteroids – they "feel the danger is to great to ignore" – so they're keeping a lookout for asteroids that might be on a collision course with Earth.

The taps mean different things.  It is explained in the explanation.

Explanation:

1 tap - Announces the result of a vote, to get attention, or to indicate to the members that they should be seated, ends meeting.

2 taps - Calls the meeting to order.

3 taps - Indicates to all members that they should rise/stand.

Series of Taps - Restores order in the meeting.