After 4 years of reading, I have completed all 54 books of the Horus Heresy. Onward to the Siege of Terra! #Warhammer #HorusHeresy

It feels good to be working on a microlensing project again after all these years!

Update: I finally solved the DNS issues and all versions of the Habitable Zone Gallery URL are now working. www.hzgallery.org hzgallery.org www.hzgallery.org hzgallery.org

I'm very excited for the ESA PLATO mission, for several reasons. One reason in particular: it will be a mean, lean Venus-analog finding machine that will greatly increase our ability to explore the Venus/Earth divergence. Read more in my new paper here: arxiv.org/abs/2607.14225

The Expected Yield of Venus Zone Terrestrial Planets from PLATO

The characterization of terrestrial exoplanets and the conditions that lead to divergent climate outcomes is a primary goal of exoplanetary science. The Venus Zone (VZ) provides a framework for identi...

arxiv.org

15 years ago, @dawngelino.bsky.social and I launched the Habitable Zone Gallery. To celebrate this milestone, we are proud to announce a significantly revamped site, with new aesthetics, features, and plot options. Check it out here: hzgallery.org.

Apply now to join the research group of my amazing colleague, Joana Voigt, here at UCR! Joana's group focuses on planetary volcanology (www.joanavoigt.com). More details regarding the position are provided in the attached images.

Tonight’s fireworks has competition. Venus is blazing in the western sky, a steady planetary lantern above all that beautiful human thunder. A reminder that not all fireworks are made on Earth. Happy July 4th!

Masters of the Universe was the most fun I've had at the cinema in years!!

He-Man: I Have The Power Meme

ALT: He-Man: I Have The Power Meme

static.klipy.com

Don't forget to watch for Jupiter and Venus together after sunset! On June 9 they'll be very close but even now it's good. Look west after sunset. If it's clear you can't miss them lowish to the horizon. Venus is very bright.

My new paper explores the dynamical stability and habitability of the nearby HD 20794 system. The outer planet follows a highly eccentric orbit through the habitable zone, raising exciting questions for climate, architecture, and future HWO observations. arxiv.org/abs/2605.26217

Dynamical Stability and Habitability in the HD 20794 System

The Keplerian orbit of a terrestrial planet can be a significant driver in the evolution of surface conditions, as well as influencing the overall dynamics of the system. The HD 20794 system harbors t...

arxiv.org

Without giving anything away, the end scene of "Hunters" season 2, episode 6 may be one of the most beautifully haunting things I've ever scene on television. Never forget!

If you've had a long day, go outside after sunset and admire the view of our beautiful planetary companions Venus and Jupiter toward the west, along with the first quarter moon overhead. It's soothing for the soul!

I love this new paper about planets in AGN disks around supermassive black holes! arxiv.org/abs/2605.19241 Naturally, it also helps to motivate some of the crazy planetary systems I've built: planetplanet.net/2018/06/01/t...

Active Galactic Nucleus Tori: Potential Birthplace to Millions of Planets

The outer regions of AGN disks have temperatures similar to those of circumstellar disks, permitting dust condensation. Therefore, planet formation and growth could be active in these dust tori throug...

arxiv.org

The universe is likely filled with Mars-size planets, more so than Venus and super-Earth size planets. So what does Mars teach us about the evolution of planetary habitability, and the detection prospects for its exoplanet cousins? arxiv.org/abs/2605.18949

I'm happy to share my new paper, in which I explore early Venus as a climate puzzle: how rotation, obliquity, eccentricity and a fainter young Sun shaped insolation and seasonal forcing before its greenhouse end state. link.springer.com/article/10.1...

Seasonal insolation variability on early Venus: implications for energy budget - Astrophysics and Space Science

Venus and Earth are similar in bulk properties yet followed dramatically different climatic trajectories. Reconstructing the climate evolution of Venus requires understanding how variations in rotatio...

link.springer.com

Venus is blazing in the western evening sky right now, and every time I look at it I’m struck by the contrast. To the eye it is serene and beautiful, yet the surface is one of the most hostile known locations. That visual tension is one reason I find Venus is so interesting.

Venus advocacy is also exoplanet advocacy. Every improvement in our understanding of Venusian climate history, atmospheric loss, surface–atmosphere coupling, and volcanism sharpens how we interpret terrestrial exoplanets.

I'm extremely proud of my friend and colleague, Michelle Hill, for her brilliant work in investigating the effects of planet size on sustainability of atmospheres and habitability. arxiv.org/abs/2605.00170

Smaller Than Earth Habitability Model (STEHM): The Lower Size Limit for Atmosphere Retention in the Habitable Zone

With recent advances in exoplanet observational techniques enabling the discovery of increasingly smaller planets, a crucial question emerges in the search for habitable planets: how small can a plane...

arxiv.org

We have a new paper out in PNAS led by Charlotte Minsky! Our research indicates that around 700 million years ago, Earth's climate may have been just One Snowball After Another. sciencex.com/news/2026-04... www.pnas.org/doi/10.1073/...

Snowball Earth may hide a far stranger climate cycle than anyone expected

During the Sturtian glacial period during the Neoproterozoic Era, Earth underwent periods of global glaciation, which have been described as either "Snowball" and "Slushball" Earth scenarios. In Snowb...

sciencex.com

As we move toward direct imaging and better atmospheric characterization of rocky exoplanets, Venus becomes even more important. We are going to need robust spectral and physical intuition for worlds that are cloudy, hot, chemically complex, and not remotely Earth-like.

A big reason I advocate so strongly for Venus missions is that Venus is not a niche topic. It sits right at the intersection of planetary interiors, atmospheres, climate evolution, and exoplanet interpretation. The Venus story improves a huge fraction of planetary science.

Venus’s atmosphere is a time capsule under pressure. Noble gases, isotopes, and trace chemistry can tell us whether Venus followed a fundamentally different path from Earth, or whether it began more clement and then changed profoundly over time. DAVINCI will provide the answers!

One of the many things I love about EnVision is the mindset: Venus is a connected system. Interior, surface, atmosphere, and climate evolve together. To understand why Venus and Earth diverged so dramatically, we have to study those links directly.

VERITAS is exactly the kind of mission Venus needs: high-resolution radar, topography, and surface composition at global scale. That’s how we move from debating resurfacing and tectonics to actually testing them.

Every serious step forward on Venus helps us interpret rocky exoplanets better. “Earth-size” does not automatically mean Earth-like, and Venus is the Solar System reminder that planetary evolution can take a very different turn.

Alpha Regio is one of the most interesting places in the Solar System. Its tessera terrain may preserve clues to ancient crustal processes on Venus, and DAVINCI is designed to explore that story by descending through the atmosphere to the surface.

Venus isn’t just our nearest planetary neighbor. It’s one of the best tests we have for how rocky worlds diverge. If we want to understand habitability, climate evolution, and Earth-size exoplanets, we need the full Venus story.

Voyager 1 and 2 continue to inspire me and they explore between the stars. science.nasa.gov/blogs/voyage...

There are two Earth-size planets in this image.