Like all good things, Leg 1 of our expedition must come to an end. But fear not, as Winston Churchill once said: this is not the end. It is not even the beginning of the end. It is merely the end of the beginning.
We’ll be back next week with Leg 2. But before that, lets catch you up with what else is new. Today’s final Nereus AUV dive ended, for the first time, with us exhausting our batteries.
Starting just after 4am, Nereus dived back to an area West of the Von Damm vent-site and continued its search further West, beyond where we had seen anomalies in EH sensor data on Nereus Dive 50, 4 days earlier. Since today was out last dive we didn’t have time to wait for the full data set to come back on deck and, instead, had scientists on watch in 2h blocks throughout the day monitoring the sparse data sets that are sent up to the ship acoustically (via sound waves) episodically, in between packets of engineering information such as the vehicle speed, heading and % battery power remaining.
Our goal was to follow a cunning plan that Mike helped me devise in which we had the ability, by sending Nereus an acoustic command, to jump ahead from a mapping survey to conducting a near seafloor survey for evidence of venting, if only I could first target where I wanted Nereus to go.
By 10:00am it was clear that we were pushing the speed of Nereus so hard (I blame lead-foot Loral) that we were going to run out of battery charge way before we completed searching everywhere I wanted to search in a single final dive. But then at 10:30 we saw evidence thatNereus was flying through plume-infested waters at 40m off-bottom.
So far so good and at 11:30, having seen nothing else more promising, we decided to roll the dice, and sent the command for Nereus to break off its larger survey and head to that spot to conduct a more detailed seafloor survey. Snake eyes. We got nuthin’. Very soon we were out of power anyway, so we hadn’t missed out too much and, later in the day, Mike showed me some very cool photographs that Nereus had collected the previous day – I’ll share some of them with you tomorrow.
In the meantime, with an hour to the surface, I goofed off for 30 minutes with one of our engineers; Götz, in the mess taking photographs from inside waves as viewed through the portholes. [Don’t panic – it isn’t that the waves are specially rough, just that the mess sits low in the water so we can look out over the ocean surface when we are eating: very cool, specially here on the Mid-Cayman Rise where the ocean is so blue]. I’ll share some of Gotz’s pictures with you tomorrow – but not until I’ve shown you mine [ I’m jealous ;) ]
All too soon, Nereus was back on the surface and then back on the ship. Because we have to leave early tomorrow morning to head to Jamaica for our mid-cruise port-call, we have since been spending a few hours stooging around near the Von Damm vent-site recalibrating all our navigation equipment. And then East we go all tomorrow and tomorrow night to Montego Bay – it’ll be nice not to set my alarm clock for 3am tomorrow and, instead, go for a nice Sunday drive.
If you’re reading this in Wales, or anywhere else that celebrates it this weekend: Happy Father’s Day!