diff --git a/www/penumbra/journal/canvas-and-matrices/index.md b/www/penumbra/journal/canvas-and-matrices/index.md
index 8c5ef8c..8bfd468 100644
--- a/www/penumbra/journal/canvas-and-matrices/index.md
+++ b/www/penumbra/journal/canvas-and-matrices/index.md
@@ -4,6 +4,7 @@ layout: article
 title: 'Chapters 2–4: Canvas and Matrices'
 date: 2023-12-08 18:30:00 -07:00
 image: pixel-clock.jpeg
+imageAlt: Screenshot of the pixel-clock component demo
 teaser: >-
   An overdue and long update covering 3 chapters! The site has moved to its permanent home
   and the demo for these chapters is a neat little animated clock.
diff --git a/www/penumbra/journal/github-copilot/index.md b/www/penumbra/journal/github-copilot/index.md
index aefd0b6..7e60801 100644
--- a/www/penumbra/journal/github-copilot/index.md
+++ b/www/penumbra/journal/github-copilot/index.md
@@ -4,6 +4,9 @@ layout: article
 title: 'How I Am Using GitHub Copilot'
 date: 2024-03-23 15:15:00 -07:00
 image: poster.jpeg
+imageAlt: >-
+  Screenshot of the JavaScript and WebAssembly versions of the sphere-shadow components.
+  Copilot, the GitHub Copilot mascot, looks up at the demo.
 teaser: >-
   A six minute video I produced to show how I am using GitHub Copilot as I work on
   my ray tracer, Penumbra. Includes a preview of the upcoming switch to Rust/WebAssembly!
diff --git a/www/penumbra/journal/ray-sphere-interactions/index.md b/www/penumbra/journal/ray-sphere-interactions/index.md
index 5a06950..f4afdd4 100644
--- a/www/penumbra/journal/ray-sphere-interactions/index.md
+++ b/www/penumbra/journal/ray-sphere-interactions/index.md
@@ -4,6 +4,7 @@ layout: article
 title: 'Chapter 5: Ray-Sphere Interactions'
 date: 2023-12-29 14:00:00 -07:00
 image: sphere-shadow.jpeg
+imageAlt: Screenshot of the sphere-shadow component demo.
 teaser: >-
   Finally! Ray casting! Plus an interactive demo of a sphere’s shadow.
 ---
diff --git a/www/penumbra/journal/rust/index.md b/www/penumbra/journal/rust/index.md
index 11cbd54..adb3644 100644
--- a/www/penumbra/journal/rust/index.md
+++ b/www/penumbra/journal/rust/index.md
@@ -4,6 +4,10 @@ layout: article
 title: 'The Twist You Possibly Expected: Rust'
 date: 2024-06-04 13:20:00 -07:00
 image: preview.jpeg
+imageAlt: >-
+  Screenshot of the JavaScript and WebAssembly versions of the sphere-shadow components
+  side-by-side. There is also a dropdown menu to select the resolution that the components
+  will render.
 teaser: >-
   Switching from JavaScript to Rust/WebAssembly has (unsuprisingly) significantly increased
   performance!
diff --git a/www/penumbra/journal/tuples/index.md b/www/penumbra/journal/tuples/index.md
index 653f1a1..e601239 100644
--- a/www/penumbra/journal/tuples/index.md
+++ b/www/penumbra/journal/tuples/index.md
@@ -4,6 +4,7 @@ layout: article
 title: 'Chapter 1: Tuples'
 date: 2023-11-18 19:51:00 -07:00
 image: projectile-cannon.png
+imageAlt: Screenshot of the projectile-cannon component demo.
 teaser: >-
   An interactive web component already!
 ---