Two events are coming up that be watched Live on NASA TV.
Firstly the Mars MAVEN orbiter will reach the Red Planet after its ten month journey there. NASA TV will have live coverage of the event on the 21st or 22nd of September (depending on where you are on Earth)–9:30PM Eastern US Time on the 21st.
There’s a good video explaining the MAVEN here on Space.com.
Secondly the SpaceX Dragon resupply module will be shown docking live with the ISS on 22 September at 11:30AM Greenwich Meantime/ UT.