For a few hours this afternoon, the moon will obscure our view of the sun. For those unable to get to a solar eclipse watch party or prime viewing location, NASA is offering a livestream of the phenomenon.

In Philadelphia, the eclipse will hit its peak at 2:44 p.m. (The moon starts to obscure the sun here at 1:21 p.m.; the sun will again be fully revealed at 4:01 p.m.) There is a chance that cloud cover could hinder views.

At 3 p.m., shortly after the eclipse's height here, Derrick Pitts, the chief astronomer at the Franklin Institute, will take your questions in a Facebook Live Q&A on's Facebook page.

Pitts will be answering questions from Saint Joseph, Mo., which is in the 70-mile wide swath of the country that will see a full eclipse. In Pennsylvania and New Jersey, a partial eclipse is in store, with most places seeing about 75 percent cover.

Those viewing the eclipse in real life should use solar-eclipse glasses for protection. The glasses, which have been in high demand in the days leading up the eclipse are necessary to prevent harming your eyes while sungazing; regular sunglasses are not sufficient.

The Philadelphia area last saw a total eclipse in 1478. The next full eclipse here isn't expected until 2079.