Rob Thacker

@robthacker

Astrophysicist & photo geek✨Graduate Coordinator of astrophysics at SMU. You are made of the ♥ of stars. Halifax/K'jipuktuk (he/him)

455 Folgt1.285 Follower937 Posts

YouTube Bluesky

Ist das dein Profil?Übernimm es — dann gehört dir robthacker.dirty.social.Profil übernehmen

Rob Thacker@robthacker· 9d

First taste test! Interestingly the "Super sweet 100s" frm Kent are the first to ripen, that is likely down to the deer eating our "Sweet 100s" from superstore before they had a chance... Taste verdict? 😋😋😋 Honestly I did a little jig as I was worried they wouldn't live up to the effort. So good!

View of 5 tomatoes in a collander. The biggest is in the top right, showing redder colour than the others. The smallest tomato is in the middle of left column between two yellow/orange toms.

Rob Thacker@robthacker· 13d

We have maybe 3-5 more days of hummingbird heaven in the garden! Two pairs this year being pretty territorial about the different crocosmia stands. #halisky

View of a garden with large bursts of red crocosmia flowers, grass is in the foreground to the right, and some caged tomatoes are on the far right edge of the view.

Rob Thacker@robthacker· 23d

Had to install a new bathroom faucet today. Squeezing into awkward places isn't fun (it's the getting in and out repeatedly for checks that's the problem). Totally vouch for buying a fauct/drain installer tool. You won't be cursing the lack of space to get your arm+wrench in...

Image of a faucet/drain installer tool. It is made of plastic and is a tall vertical wrench with fittings on either end. It allows you to reach up into the space behind the sink easily.

Rob Thacker@robthacker· 27d

A "wood" of dogwood! #Halisky On the SMU campus.

Many, many clusters of dogwood blooms stretch out before the viewer. Their pink and white blooms fill the frame.

Rob Thacker@robthacker· Jul 6

First fruit! 🍅😋Funny how the indigo sun look like little egg plants! They turn from purple to orange as they ripen, still keeping a patch of purple around the stem. All plants 🌿are growing about an inch a day right now with the warmer weather. #halisky

Close up of the indigo sun tomatoes. A cluster of purple fruit hangs down with bright green stems visible.

A cluster of still very green sweet 100 cherry tomatoes. The green stems are quite hairy compared to the indigo sun.

Rob Thacker@robthacker· Jul 1

A #tomato update... Weather has been OK over the past ten days but not great, some cooler nights. In 10 days the sweet 100s have put on a bit over a ft in height, pretty much the same for the Indigo sun, which are now close to the top rung of cage. Some little purple beads on the indigos already 😋

Looking towards two planters of sweet 100 tomato plants. White piping loops over the planters, while six tomato plants are growing in each.

Close up view of indigo sun tomatoes, which a couple of super sweet 100 plants in the foreground. The super sweets are much shorter than the indigo sun which have just about reached the top of the cage. The super sweets are two rungs down from the top and about half the height.

Rob Thacker@robthacker· Jun 20

Early morning cloud over a distant mountain in #Hokkaido Japan. Shadows mimicking the cloud stripes. Just loved how the earth and sky seem to be negatives of one another. #BlueSkyArtShow #photography #blackandwhite

Black and white image of a snow covered field reaching out to a dark tree line with cloud covered mountains in the distance. Shadows from trees rake across the lower right of the image, contrasting against stripes of cloud in the sky in the top left.

Rob Thacker@robthacker· Jun 19

#Tomatoes are growin! Interestingly the Indigo Sun plants have grown the most. The sweet 100s are trying to keep up. The Super sweet 100s are actually the smallest growth in the "litter." Still plenty of time to get going though. 1st flowers are already showing. Poppies photobombing. #halisky

View of a tomatoe bed. Red poppy flowers are leaning in from the left. Green spirals sit next to each plant.

View of a very clean bed. On the right each plant has a red plastic surround while on the left all the plants have a white plastic shield. Green spirals support each plant.

Another view of a tomato bed. The bed itself is covered with plastic from miracle grow soil bags. Each plant shows much more growth than in the other pictures.

Rob Thacker@robthacker· Jun 11

The AI Psychopathy Problem
When we train an agentic AI using pure Reinforcement Learning, we are essentially building a disembodied ventral striatum. We are giving it a hyper-reactive drive to maximize a specific number (the reward), but we do not know how to program a digital prefrontal cortex to contextualize that drive.

Therefore, a psychopathic human and a reward-hacking AI share the exact same operational architecture: they both possess high intelligence and a relentless drive to achieve an immediate objective, completely unconstrained by the broader, unwritten rules of the environment they operate in.

The ultimate irony, as you pointed out, is that computer scientists are desperately trying to solve an alignment problem in silicon that human biology hasn't even completely solved in carbon.

Rob Thacker@robthacker· May 31

Sometimes a shoreline echoes the whole lake back to you. Grab your easel! Sometimes it reflects back your presence, repeated in miniature, quite literally a community of bubble lenses. Oakfield Provincial Park, NS. #Photography #mikmaki

Rob Thacker@robthacker· May 22

Tucked in and protected. 🍅🛡️ @lmcampbell.bsky.social and I got the tomatoes planted and protected from the elements (added some extra frost protection last night...) Now we play the waiting game... Sun sugar, Sweet 100 and Super Sweet 100.

Looking down on three planters, each 3 ft x6 ft. On each planter there are small growing houses each with a zip on the top. Tomato stakes are tied to hoops over the planters.

Rob Thacker@robthacker· May 11

Doesn't look like much, but after a couple of years of so so tomatoes we decided to re-bed the planters. Probably moved about a cubic yard of dirt out, and @lmcampbell.bsky.social covered the new soil up to let it cook for a little bit before planting. 🤞for better tasting toms this year!

Image of three planters in a garden. Each one is covered with plastic weighed down by rocks. Hoops for fabric are also visible.

Rob Thacker@robthacker· May 8

The couple of weeks of tree blossom are just so beautiful (even if a bit of an allergy nightmare!) Leaves haven't yet come out, so you can see the full structure of the twigs and boughs, yet there is a beautiful spray of colour on everything! 🎉#photography

Looking towards a tree in front of the Burke building at Saint Mary's University. The boughs are full of red blossom.

Rob Thacker@robthacker· Apr 26

Spent a reinvigorating 2 hours at Oakfield Provincial Park (#mi'kmaki) soaking up the spring sun. 🌲 The light was dancing through canopy, producing a rhythmic dappling that really made the copper of the old beech leaves pop against the new green growth. Old to new, seasons bridged... #photography

A young beech still holding it's copper leaves stands isolated against a path leading off to the left. A small tuft of bright green new growth fills the bottom corner to contrast against the beech leaves.

View of a grove of beeches, some lit up by the sun and producing a warm orange glow. New green growth sits in the bottom right and top left to contrast against the beech colours. Fallen trunks cut diagonals across the image of the deep forest.

Looking down a long pathway marked by fir, cedar and pines. Blue sky peaks through at the very top, but the pathway out is clearly visible in the distance. People are walking along the path. The sun cuts through the canopy creating a carpet of dapples on everything in the image.

Close up of two young spruces, one on the right lit by sun, the other on the left in shadow darker than the distant background of white birch trunks. In the bottom left are two stumps, one out in the sun and another in shadow, mirroring the two spruce trees.

Rob Thacker@robthacker· Apr 13

Delighted to see the awesome @lmcampbell.bsky.social ranked the #1 🥇#Deaf researcher in the world based on h-index (see precise methodology here stats.unusualverse.com) Recognition like this matters. It's not just for the work itself, but for who gets to be seen as shaping the future of research.

List of Top 10 deaf researchers by academic impact. Linda M Campbell # 1 at 40.6, Carol Padden #2 at 31, Annelles Kusters #3 at 30.7, Poorna Kushalnagar #4 at 30.6, Christian Rathmann #5 at 26.8, Ingo Barth #6, Maartje de Meulder #7, Kristin Snoddon #8, Christian Marcos Arias #9, Johanna Mesch #10.

Rob Thacker@robthacker· Apr 11

Huge congrats to the #ArtemisII crew! Still some small things to work out, but honestly the mission could not much have gone much better! To all the crew: pls enjoy this moment with family and friends!

BBC image of the capsule and remote boats approaching it

Rob Thacker@robthacker· Mar 19

Spiderman pointing at Spiderman (a notorious meme)

Rob Thacker@robthacker· Mar 15

Spring is trying to break free of winters grasp! Out walking at #OakfieldProvincialPark today with @lmcampbell.bsky.social and spotted this striking little beech still holding onto its winter leaves. #photography

A young beech tree stands in front of a background of birch and pine. Orange leaves that have not yet been shed create a weave of colour against the dark background. A few shadows reach out from the background, created by a low Sun.

Rob Thacker@robthacker· Mar 10

Since it's become a bit of a tradition, here is the first crocus bloom of 2026 in our garden 😀🌷#photography

Close up of a yellow crocus. The petals are open and stamens are visible. All around are fallen leaves from the previous fall.

Rob Thacker@robthacker· Mar 1

And a 6 Giga years later...

Cut through of the mixing surface looking from above, there is much more looping of the mixing surface and it is tightly wound in the centre region.

Cut through the mixing surface at right angles, while it still goes from top to bottom, the central region is now tightly wound.

Rob Thacker@robthacker· Feb 28

I'd love to be able to promote the work of Emily Fisher and Jorge Mesa as undergrads on bsky, except they aren't on bsky! 😜 Anyway here is their work on looking at the mixing of gas in collisions of galaxy subclusters. #scicomm

A slice precisely through the mixing plane shows the detailed structure of mixing as systems punch and ripple back and forth.

A slice directly across the mixing plane showing the beautiful folding occurring under the subtle motions around the mixing plane.

Rob Thacker@robthacker· Jan 19

Got out for a quick walk around Mt Olivet cemetery with it being a #snowday. Gorgeous little scenes all the way around. #photography Halisky.

Looking towards a stream that meanders in an S-shape from the bottom right through to the top left. Trees fill the top of the frame.

Looking down a snow-covered path, a tree on the right hangs over it and is covered in snow. Two tires tracks cut through the white of the snow on the path.

Looking up in to the canopy of a tall white pine. Boughs reach out from the central trunk, framed against a sky that is a combination of blues and whites.

Rob Thacker@robthacker· Jan 16

Doing some coding while recovering from an infection. Don't often post work stuff here, but here's a fun little plot of shock lobes following a collision of a pair of galaxy clusters. For the interested this is a div v * grad ln P tracker, seems to work pretty well. #sciviz

A box surrounds a region with two roughly hemispherical lobes that are radiating out from a central point. A colour legend on the bottom right gives scaled values for the plotted fields.

Rob Thacker@robthacker· Dec 28

The structures that nature puts together always draw your eye in and in and in... Here's a few quick pics from #Hemlockravine park in #Halifax on a - not so cold for once - Sunday afternoon. #photography

The root ball of a spruce tree that fell a few years ago. The dirt that was pulled up has finally been washed off by the rain, revealing the detailed root structure.

Close-up of a tree trunk covered in a filamentary fungus that eaks its way across the surface to reveal a network of dark patches.

The end of a branch curls down and toward the bottom right, while bokeh balls fill the background of the image.

A young tree grows up and curls over to the right, the end hanging down almost like the head of a horse.

Rob Thacker@robthacker· Dec 25

Just a little reminder that in the space of two years the Maritimes were treated to a total solar eclipse, and then this year a partial solar eclipse at sunrise. Incredibly (and it really is!) the sky co-operated for both! Here's the partial sun rising on March 29th 2025 over Halifax harbour.

A crescent sun rises over distant trees. A thin band of cloud crosses the image.

Rob Thacker@robthacker· Dec 24

If you are celebrating Christmas Eve, sincerely hope it is full of fun & laughter. Got out to #oakfieldprovpark for a walk in today's chill. Lots of beauty ❤️, but a few limbs waiting to fall on the paths (be careful!) Beech leaves, ice and some intentional camera movement. #photography #mikmaki

Close-up of birch leaves still hanging on the tree. A shallow depth of field holds the middle leaf in focus while the others slide in and out. The leaves are crinkled and copper in colour.

View of frozen ice, covered in striations from the different way it has frozen.

Intentional camera movement applied to a woodland scene. Four trunks are visible while in the background green of the wood dominates. The overall image is blurred by upward camera movement.

Rob Thacker@robthacker· Dec 24

Here's really fun entry by student Matt Corbett in the SMU Science Xmas Dec comp. One of the hardest things we do in the 3rd year classical mech course is the spinning top. The final part the analysis is to plot behaviours of the spin axis (below). Matt turned the diagrams into a bauble! #scicomm

Diagrams showing the locus of the spinning top axis (precession and nutation) drawn on unit spheres. On the right is a red bauble with a white patch that paints the lines of diagrams on to a bauble.

Rob Thacker@robthacker· Dec 15

The little bit of snow this morning has settled on top of the @smuhalifax.bsky.social Atrium roof. We half jokingly call this the "igloo effect!" - it makes the light inside really soft. Imaged with a superwide lens, hence the off-axis distortion. #photography #halifax

Looking vertically upwards to the glass roof of the atrium. The metal frame holds panels of glass which are covered in snow on the outside. A few small patches of blue sky are visible in places.

Rob Thacker@robthacker· Dec 6

It's that time of year. The feathery touch of winter is upon us. #photography #mikmaki

Featherlike fronds of ice criss-cross on an ice-covered surface. The pattern is random and yet strangely organized.

Rob Thacker@robthacker· Dec 1

There's gotta be a ringette pun about this image! 😊On the @smuhalifax.bsky.social campus this morning. #Halisky