I heard about this one in the weekend and it quite intrigued me... I've put in a couple of links with the first one being a good introduction for the children.
http://www.vox.com/2016/7/28/12310762/mysterious-purple-orb-nautlius
https://www.theguardian.com/environment/2016/jul/30/submarine-scientists-crab-mysterious-glowing-purple-orb

Play the video  and a have a listen to the scientists discussing what they can see as well as their description of it. I really like how they try to describe the purple orb as well as how they are going to grab the orb. It is funny that they use those dreaded metaphors and similes!
Once it has been sucked up, they talk a bit more about what it might be and one questions another's guess about would it be that easy to identify? What might the scientists do to try and identify this creature? What might they be looking for? What patterns (comparing to other creatures) as well as structures (organs, etc) would they look for?
The Guardian link has a bit more detail and what the creature looks like as well as what it might be. I won't give away the surprise but some of the more  able readers might be able to read the whole article.

As I watched the video, I did wonder why none of the scientists were concerned about sucking up this creature -what if it was the only one of its kind? Were they comfortable that their lab had the right environment to house the organism? Will they put it back?

I like this kind of science news article -I'm thinking about turning it into a newsboard, just for a quick watch and discussion. It might catch some students who want to find out a bit more which I always like -that's the last capability Engaged in Science where children are self-engaged. I also like this one because it enables children to hear scientists chatting -they seem to think the same as us... In fact wouldn't it be interesting to play the video with no sound to hear what we are thinking, talk about that and then play the video again with the sound up... Were their conversations similar to ours? I think they would be quite similar apart from the extra knowledge that the scientists have about deep sea creatures!

Have fun!