Do I need to play Chains of Satinav first, or can I jump right into this one?

Yes, it would be better to play Chains of Satinav first.

Ok, thank you. :)

I might disagree. As someone who just finished Memoria I can say that having played Chains of Satinav is recommended but by no means necessary.

You will understand Memoria 100% and lose nothing by not having played Chains. The biggest issue to consider, however, is the ending of Chains which figures rather heavily into Memoria from the start. Memoria only barely glazes over a mere mention of what happens, but it only takes a few minutes on youtube to see it for yourself.

That being said, playing Memoria will effectively spoil the ending of Chains in that regard. So if you wish to avoid spoilers, you will want to play the story in order.