Royal icing, waited for it to mostly dry, then painted it with watered down food coloring.

🌌 Major milestone for DESI: full originally planned survey footprint was completed on April 15, ahead of schedule!
47M+ galaxies & quasars mapped → the largest 3D map of the Universe ever made.
Keep posted: Observations continue through 2028.
More: tinyurl.com/Y5DESI
#DESI

No, just the oven. The cake equation of state has a time-dependent w (like the universe, maybe!).

DESI Completes Planned 3D Map of the Universe and Continues Exploring The Dark Energy Spectroscopic Instrument (DESI) has completed its originally planned five-year mission and will continue.

An exciting astronomy milestone was hit last night, as DESI completed its original 5-year survey mapping 40 million galaxies in the night sky!

DESI continues operation, now aiming for an 8-year survey and ~60 million galaxies. 🔭🧪 #cosmology
newscenter.lbl.gov/2026/04/15/d...

The flavor is dark energy (espresso dark chocolate).

Yes, many!
You might try Klaus Honscheid or Samuel Brieden. We even have a German version of the DESI planetarium movie.

I made this cake 2 weeks ago and had to wait for the embargo to lift 😆

A teal hour-glass shape created by dots of the many galaxies DESI observed. An enhanced inner section shows how they trace out large-scale filaments and voids.

Here's our official press release, featuring some of the graphics I worked on. I'm especially happy with this updated butterfly map.
newscenter.lbl.gov/2026/04/15/d...

A black, single-layer cake. The top is decorated with a pastel-rainbow telescope and galaxy map behind it.

A different view of the cake, showing the galaxy map spilling over the side.

DESI finished its originally planned survey last night!! ..and will keep going :)

I made a cake to celebrate. 🌌🔭
@desisurvey.bsky.social

Outline of a fancy mouse with cool glasses

"Mus Elegans" found by Strawberry Shortcake

"The Void Screams Back" found by i looked too close i looked t-

A grinning outline of the popular meme 'pepe'

Someone put too much time into this one

Simple outline of a large bannana

"Banan" found by Monke

A large lambda symbol

"evidence for LCDM" found by einstein

"Bob" found by Bob

A simple line drawing of a croissant in a dense galaxy field

"Croissant" found by Crustulum

the outline of OHIO. "OHIO", found by OSU astro coffee

I'll start with the one we made at OSU astro coffee this morning.

This was fun to make and I hope ya’ll check out the paper and try making some of your own galactic constellations. 🌌
Paper: arxiv.org/abs/2603.29912
Website to find galactic constellations: cmlamman.github.io/galactic-con...

So what are galactic constellations? They are an unconventional cosmological probe, a fun art project, a way to engage with DESI data, and a continuation of one of humanity's oldest traditions.

Side note: this is an unexpected outcome of the website! None of the users were aware of this application and most were unfamiliar with cosmology.

Humans did not identify distinctive shapes on large scales, matching where we expect physical coherent structures to disappear. …so “Cow Tools” is consistent with LCDM.

A plot of constellation size vs the size of the image they were identified in. The sizes of constellations consistently fall below 400 Mpc/h, regardless of image size.

But at what point do you go from distinct patterns to a smooth universe? Let’s look at constellation sizes. Even though they were often looking at slices of DESI’s map that spanned massive distances, users consistently picked out shapes below the threshold where the cosmological principle applies.

Can these constellations tell us anything about cosmology? Actually sort of yes.
The cosmological principle underpins all of standard cosmology and states that the universe is homogeneous and isotropic on large scales. I.e. everything should look smooth and even if you zoom out far enough.

Small white dots of galaxies on a black background. Several nonsensical shapes are outlined in semitransparent teal lines.

The most popular constellation is “Cow Tools”, a reference to a non sequitur comic and internet meme (Larson 1982). Cow Tools demonstrates the profound and immutable nature of constellations beyond geometric shapes: they are cultural artifacts that encode the shared mythology of the civilization that names them.

I got friends and family to test this out, resulting in 93 new constellations. Some of them are very good, but the most popular one is currently “Cow Tools”. I’ll let the text of my paper speak for itself here.

To find more galactic constellations and give anyone the opportunity to discover them, I developed a public website: cmlamman.github.io/galactic-con...
You can flip through random slices of DESI data, create and submit new constellations, and see what others have made.

three panels of clustered galaxy positions, shown in black points. In colored points are galaxies which trace out stick versions of a fish, a person, and a ‘W’.

DESI’s first public data release contains distances to 14 million galaxies. We explore the most complete part of this map using a biological neural network (Complex Learning And Introspective Reality Engine). This led to the discovery of several new constellations!

Humans have lovingly recorded constellations for at least the past 5,000 years, but seem to be running out of ideas (Lund 2025). Within the past 50 years, we have mapped out millions of galaxies and unleashed a new frontier of finding fun patterns in the sky.

Galactic Constellations in DESI DR1 and the Scales of Cosmological Homogeneity We present galactic constellations: charming shapes in large cosmological surveys. By exploring a dense subset of DESI's first data release, we discover distinctive constellations including "Pisces Gr...

New paper on the arXiv today!! We discover constellations in DESI’s galaxy map and explore their cosmological implications. Here’s a thread of the key results. 🧪🔭

Paper: arxiv.org/abs/2603.29912

Website where you can find your own galactic constellations: cmlamman.github.io/galactic-con...

Either can fall in, the distinction for this heuristic example is a matter of convention. In the comic I actually did not explicitly label one as the antiparticle. What's important is that whichever particle falls in will end up having negative energy as measured by an outside observer.

This is a good point. Justice for antiparticles ✊