On July 3rd, NEOWISE came closer to the Sun than the orbit of Mercury, and that flyby caused much of the icy material to cook, erupting as gas and dust. NEOWISE is a pretty sizable comet, too, measuring about 3 miles (or 5 kilometers) across, which is why we can get this great view of it from Earth.
For much of last week, NEOWISE has been showing up just above the northeastern horizon, about an hour or so before sunrise in the Northern Hemisphere. People have been able to spot it best with binoculars, though some claim to be able to see it with the naked eye. And many astrophotographers have captured stunning images of the comet in all its gassy glory just before the Sun comes out, including the astronauts aboard the International Space Station.
Around July 11th, though, the comet will start to appear in the evening just after sunset. It’ll be in the northwestern sky, below the Big Dipper constellation (or Ursa Major). Mainzer expects the comet to be visible for at least another week, maybe even longer.
Stellarium web is a good tool to preview where the comet will be.