On July 4th, NASA is going to bash a large plug of copper into a comet (discovered in 1867 by Ernst Temple). Nobody's sure exactly what will happen — which is the main reason to do it — but it should make a sizable crater in the comet and generate a plume of ejecta.
NASA seems to like to schedule landings and other such events to coincide with holidays (July 4, December 24, etc.). Not only are people at home and watching TV, but NASA's copywriters often try to manage some sort of tie-in. The resulting headllines can be agonizing.
In 2000, the Near Earth Asteroid Rendezvous (NEAR) spacecraft arrived at an asteroid (basically, a large rock) named Eros. A 1999 encounter had failed, and the spacecraft had to take more than a year to swing around again, so I believe the February 14th date of the encounter was a coincidence. But it generated endless headlines about Romancing the Stone in a Valentine's Day NEAR-Eros tryst, etc., etc. I shudder to imagine the headlines this year's unprovoked Independence Day attack on Comet Temple might generate in the USA or abroad.
In part, NASA designs its missions as public performace art and then tries to spin the missions to appeal to headline writers — but the agency is simply an inept storyteller. NASA's unmanned robotic missions are incredibly cheap, completely safe, visually and conceptually dazzling to the public, and hugely productive scientifically — especially when compared to the wasteful and dangerous manned space program. Nothing NASA has done in the last 30 years has inspired more interest and support than missions like Voyager, Viking, the Mars rovers, or the Hubble Space Telescope. The credit for these successes goes not to the cleverness of the PR department or the cuddliness of the astronaut corps, but to the skill and creativity of NASA engineers and scientists. Just go with what you do best.