Half the team is back at Rothera

— Romain Tartese | 10 Jan 2020

Hi there, quick update to let you know that Wouter, Geoff and myself have made it back to Rothera yesterday evening. On Wednesday evening we were told that the plane was coming to uplift the first 3 people the next day, so it was all a bit of a mad rush to move camp from the blue ice a few kilometres up to the skiway where the plane is able to land. Fortunately we had already started packing some of the kit away — all in all we finished setting up camp at the skiway at around 3am Thursday!

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Packing up camp on the edge of the blue icefield [Credit: R. Tartese]

Pilot Dave and co-pilot Tom arrived around mid-day to pick us up, and soon we were on our way to Rothera. Flying north we had great views over the Shackleton Range — there are loads of blue ice areas there (see photo below), who knows how many meteorites are sitting there at the surface waiting to be picked up…

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Flying north over the Shackleton Range [Credit: R. Tartese]

Antarctica being Antarctica, soon after having passed the Shackleton Range we diverted to Halley rather than Rothera as the weather had degraded over the ice shelf. It was nice to spend a last night in Halley (huge thanks to all the folks there for all their help throughout this project!), and we did make the most of hot shower, which was more than welcome after 4-5 weeks in the field!

We finally managed to get back to Rothera yesterday evening after a nice day flying over the Ronne Ice Shelf and up the Peninsula. Katie and Taff are still in the field, and should be picked up in the coming days. In the meantime, there is a fair bit of laundry to do, sorting out the science kit and getting things ready for being shipped North, and getting some rest!

The end of the sledge (but not the end of the story)…

Geoff Evatt | 08 Jan 2020

Hello from Outer Recovery, where with mixed emotions we bid farewell to our subsurface meteorite detector systems…. yep, today I had the honour of towing the single panel sledge system to the 0.75km2 area searched mark. Shortly after it errored out, a little way from where the 3 panel system finished two days earlier. We’re actually rather proud of the system, after all it did work amazingly well whilst it was working. It was the repairs between operational bouts which was the pain and has taken up our time, effort and energies.  However the undulating ice surface (see pics) took its toll: the accelerometers in the system constantly registering over 10g’s of acceleration!  In all previous testing locations (including last year’s testing on Antarctic blue ice at Sky-Blu) the system experienced always less than 6g’s, and even those were relatively rare occurrences. This constant battering from the ice meant that anything which could fail did, and once repaired as best we could, a weakness in components remained for further exploitation. Yet, the modular system of the detector had the advantage that we could continue in a fashion, and did so for 18 odd days.

Wouter in the expanse of Antarctica. [Credit: Geoff Evatt]

Fittingly, as I drove the sledge back to camp, I noticed a black dot on the ice. Yep, number 65 for the area this year. A lovely single stone, which even the sledge had a good view of. And best of all, this takes us to 101 samples for the Lost Meteorites project! It thus looks like we have almost certainly collected over 100 meteorites for return to the UK, all ready to be examined for their scientific worth and hopefully put on public display.

A small meteorite next to the now ex-sledge detector system. [Credit: Geoff Evatt]

So, did we find the layer of lost meteorites? No, the layer of lost meteorites hasn’t been found by the metal detection system, but we do seem to have found a curious fraction of iron-rich meteorites nonetheless. The immediate consequence being that further laboratory and statistical analysis is required to figure out what this implies. I say this because it raises some interesting questions both about the particular environment of the ice field the team has been searching and how this might effect the processes by which meteorites become exposed upon the ice surface. So not the in-situ grand finale we were hoping for, but equally it is not the end of this particular story…

Geoff and meteorite number 101. [Credit: Katie Joy]

In the meantime there will still be plenty of updates from the field, as we’re planning on collecting some ice samples tomorrow (much easier than collecting meteorite samples) for analysis back in the UK. After that we pack up and move camp back to the runway area, and should fuel allow, we’ll head to another neighbouring blue ice area to see what meteorites reside there. And then we await the planes (around 16th, in theory), and the statistics……

An erratic few days

Katie Joy | 05 Jan 2020

A busy few days for us in the field. We covered a bit more ground with the metal detection panel array system on the main local ice field , but then suffered a few setbacks when the system powered up and down again in a run. Geoff and Wouter had a day of taking everything apart, assessing what was working and not working, and in progress we discovered that the blue sledge (we had nicknamed Sledge Evatt Junior*) that was carrying our control box and battery had a rather large whole in the bottom, which had been allowing snow to enter the base of the sledge dislodging some of the equipment. Needless to say Junior has been now been retired, and we need a name for the new blue sledge which has taken its place (number 3 doesn’t really have a ring to it).

An ice pond next to Halliday ridge: several of the local rocks had clearly sunk into the ice leaving interesting bubble trails during their descent. Alas no meteorites. [Credit: Katie Joy]
Looking along the ridge of Halliday Nunatak. [Credit: Katie Joy]

Whilst all the fixing up has been going on, Romain, Taff and I covered quite a lot of ground surface searching the northern most part of the ice field — finding 7 more meteorite stones throughout the day, including one (a stony type) that was almost completely buried within the ice, only about 10% sticking out of this surface. The clouds lifted and the afternoon was warm and glorious to work in.

Last night we had a good 20 knot wind sweep through the area clearing a lot of the snow off the blue ice surface. We all headed out as a group of five to visit the ice field closest to the Recovery Glacier — a trip of about 10 km from where we are camped. We travelled there linked up on skidoos — forming a caravan of skidoos and sledges trundling across the sastrugi snow heading north for about an hour. BAS fieldguide Julie Baum and I visited this icefield last year (it was the site of my epic skidoo breakdown), and it was good to revisit it. We searched the surface for a while, finding one more meteorite sample (adding to the three we found here last year).

Systematic search on ice. [Credit: Geoff Evatt]
Wouter and Taff near Halliday Nunatak. [Credit: Geoff Evatt]
Meteorite collection with tongs. [Credit: Geoff Evatt]
Geological search on Halliday Nunatak. [Credit: Geoff Evatt]

We also scaled the local nunatak — the only rocky outcrop in this area**, to collect some geological samples and to take in the view of the ice fields and how they extend northways abutting the Recovery Glacier itself (the boundary between the two features is impressive, with large ridges, crevasses and ice cliffs). We assume this is a first ascent — so will take this high with pride. The nunatak is formed of a weathered igneous rock (granodiorite), but has lots what we call ‘erratics’ (they are called erratics as they shouldn’t be there geologically speaking) all over the top that have been dropped from the bottom of a glacier which used to run over the rocky peak. Tomorrow we plan to return to the metal detection panel searching and see how sledge number 3 (we really do need a better name) holds up. May his bottom not be broken.

Group ascent of Halliday Nunatak. [Credit: Geoff Evatt]

* You might be wondering what/who is Sledge Evatt (i.e., the senior). Well this bold name was given to the blue sledge that was carrying the control equipment for the first sledge unit we set up. Alas, senior had to be retired a few days ago when he also developed a large hole on his underside, passing the responsibility onto junior…

** Recently we requested to name this site Halliday Nunatak after Dr Ian Halliday (1928-2018) who was a Canadian astronomer with expertise in meteor (asteroid and comet) delivery rates to the Earth. His research is related to our core science project of understanding Antarctic meteorite type, delivery rates and glacial transport processes.

The return of blue ice

Geoff Evatt | 03 Jan 2020

Good afternoon from Outer Recovery, where I’m lying in the tent I share  with Wouter and Taff, having enjoyed a lunch of biscuits brown, soup and sardines.  Yep, austerity is in full swing! Even the cloud is down outside,  but it’s not too cold today (probably –10ºC or so).

Geoff waits out a low contrast day at camp.

We have been continuing with our search, and have covered almost 0.7 km2 with our system hanging on by its shoelaces (in fact, gaffer tape and cable ties). For clarity, that is the area our metal detector has sensed, whereas the area we have travelled over visually searching for surface meteorites is several times that. Our second system had to be decommissioned yesterday, as the huge batteries (car battery-sized) have now given up the ghost, such is the thumping the blue ice surface has been giving to everything, day in, day out. I’m hoping we will reach 1 km2 before it is no more…

Taff drives a skidoo, towing the metal detection array. [Credit: Geoff Evatt]

Simultaneous to this,  we had a bit of wind return the other evening, just long enough to remove some of the snow that recently fell (plus maybe a small bit of sublimation caused by the sun). This meant that some blue ice became visible again, and allowed for 6 meteorites to be collected yesterday and one more this morning. I think the total from this ice field is about 54, which is pretty good and spot-on for the number we had predicted given the area searched — at least the statistics are more or less behaving themselves! Weather tomorrow is forecast to be overcast again, with good weather after that. If that holds I think we’ll head to a small ice field adjacent and north of camp. There we will look for any surface meteorites,  climb the nunatak (the mountain top just poking through the ice) which we officially named Halliday, and generally get a change of scene.  And given it’s the only bit of non-meteorite rock I will have seen in over a month, it will hopefully be a welcome jaunt.

Let it not snow…

Katie Joy | 03 Jan 2020
A layer of snow covers the blue ice field. Helpful for subsurface searching; definitely a hindrance for surface meteorite hunting. [Credit: Katie Joy]

What a difference a bit of weather makes. This whole area was stunning blue ice a couple of days ago. Two days of gentle sustained snowing means that the whole icefield is now buried under 5 cm of snow. This is useful for the metal detector dragging activities (see Geoff’s last post) as it means that we can very easily see where we have driven (in the image above the panel tracks can clearly be seen in the lower half of the image, compared with the unsearched area in the upper part of the photo). On the other hand, these conditions are absolute killers for the surface meteorite searching activities as all the meteorites are now very disappointingly disguised by the snow cover. We need a night or two of 20 knot winds to come in and blow hard to shift all the snow. However, the weather is forecast to remain the same (~ –10ºC, 5 knot easterly wind, patchy sun and clouds) for the next couple of days.

In the meantime the subsurface meteorite hunting activities continue using the metal detector panels – we have now managed to search about 0.6 square km of the ice surface, with Wouter being an absolute legend fixing bits of the system that fail with all the bumping around on the hard ice surface.

Ploughing through the snow… Romain dragging the metal detection setup. The rough surface in the foreground is where the panels have been pulled through the snow creating obvious drag marks. [Credit: Katie Joy]

The benefits of snow…

Geoff Evatt | 02 Jan 2020

The cloud has lifted and progress has been made. Yep, in a true A-team style our patched-up systems seem to be working (as in, two systems with a combined searching width of 4 meters). And we searched for almost 8 hours. No subsurface meteorites,  yet (statistically,  we are only expecting a handful of iron meteorites over the entire 12km2 ice field). But what is certain is that if we’re not searching then we can’t be finding them.

As for conditions, well, it’s now all snow covered,  meaning no blue ice is visible anywhere. Whilst this makes the subsurface searching easy to progress (because you can see where you’ve been and removes vibrations in the system), it makes seeing any surface meteorite impossible. Personally I’m hoping the snow cover lasts for the rest of the trip!

The next couple of days are forecast to be similar nice weather with low winds. So let’s see if our relative fortune holds for tomorrow.