There will be a partial lunar eclipse on Tuesday 16 July 2019.
The partial eclipse on London will begin at 9.06pm and end at 11.59pm. The maximum eclipse will be at 10.30pm
Salaatul Ayat is Wajib to be prayed be between these times although it is better to be prayed before the eclipse starts to reverse.
Eclipse times in your area can be found in timeanddate.com