There are things called SIVA Clusters in Destiny’s newest expansion, Rise of Iron. To get them you need to find them first as they are scattered all across the new areas and also in the raid. Upon collecting all of them, you will have access to an exotic weapon quest so it is really worth doing that on a character.
They look like small red light stuck on walls and all you have to do is go close to them and press Square to collect them. Some of them are in difficult to reach locations but we have a video that shows you how to get them all.
There are only 30 of them and not 50 so you can do most of them in like 1 hour. Note: There are a few in the raid so you will have to complete the raid as well. You have to get to light level 365 to be able to do the raid.
Check out the video below