iiinova — where your digital self keeps evolving

Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 22/10/2025

Always wanted to show it like this. You can just about see the sine wave which marks the boundary between the hexagon and the rest of the planet, though it's very subtle.

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 22/10/2025

Let's unravel the mystery of Saturn's polar hexagon. A jet stream speeds around the pole at 320 km/h (200 mph). That’s common among planets, but what's not is that it oscillates up and down *very* stably. Each low point of this sine wave becomes a corner of a hexagon, when projected onto a sphere:

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 07/09/2025

Worst video ever, but go check out the lunar eclipse going on right now 🙂

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 03/05/2025

If you have eclipse glasses handy, check out the Sun today and you'll see a Sunspot without a telescope (if you've got modestly good vision). This is a quick pic with my phone, through eclipse glasses

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 03/04/2025

A fast stream of solar wind slammed into Jupiter’s magnetosphere, triggering enhanced auroral activity, which amplified heating in the upper atmosphere. That heat expanded the atmosphere around the planet in a thermal wave over 12 Earths long.

$Visible-light image of Jupiter overlaid with infrared data, showing the planet’s bright auroral regions at the poles and a large, arc-shaped heat wave extending toward the equator. 3 Earths are overlain for scale, covering only a fraction of that arc. Temperature scale indicates 700 degrees celsius temperatures on the feature, above the background of about 400 Celsius. The aurora are also over 700 Celsius.$

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 03/04/2025

Jupiter’s magnetic field is huge, the biggest in the solar system, and its aurora is mostly controlled from within. Here it is to scale with the Moon, if we could *see* the magnetic field lines. We found that external solar forcing plays a major role, despite this.

Illustration of the size of Jupiter’s magnetosphere if it could be seen by human eye in the night sky. It is much larger than the Moon in the sky and has a large tear drop shape, with a tail extending beyond the image.

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 03/04/2025

🚨Our new paper is out now! We caught Jupiter’s upper atmosphere reacting dramatically to a bursts of solar wind, which triggered a planet-wide wave of heat to flow from the auroras. This changes how we think about the Sun’s influence at the outer planets. www.reading.ac.uk/news/2025/Re...

Visible-light image of Jupiter overlaid with infrared data, showing the planet’s bright auroral regions at the poles and a large, arc-shaped heat wave extending toward the equator.

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 29/03/2025

Ok, I did it just because, conveniently, Stellarium include some pretend sunspots. Here I start with an Alt Az (person standing upright kinda) mount, going from 10am-noon. You can see the spots rotate in the field. At the end I switch to Equatorial mount, and then you see it stop field-rotating.

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 29/03/2025

Hans this is 'field rotation'. Chris's mount is 'Altitude Azimuth'. It's parallel to Earth's surface, like us when we stand up; watch a crescent Moon throughout the day, you'll see it rotate. 'Equatorial mounts' are tilted same as Earth's axis, so no rotation. Gif via calgary.rasc.ca/field_rotati...

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 27/03/2025

The Moon is going to block out a bit of the Sun this weekend! Also known as a partial solar eclipse, on 29th March! See the timing for your region at www.timeanddate.com/eclipse/sola... Don't look at the Sun direct, use some eclipse glasses or make a pinhole camera: www.jpl.nasa.gov/edu/resource...

A world map overlain with a shading to indicate where the partial solar eclipse on 29th March will occur. It drapes over Canada, north east United States, most of western and northern Europe, and north west Africa

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 23/03/2025

Saturn's rings are now edge-on, as the planet is at equinox. This only occurs every ~15 years, but this time around, as Saturn is on the other side of the Solar System, the Sun is largely blocking our view. It'll still be nearly edge on for months though—a fun time to see an almost ringless Saturn!

A grid of Saturn edge on. Saturn's rings look like just a black line, and Saturn is just a grid with longitude and latitude lines

The Sun, Saturn, Venus, Mercury, and Neptune appear close together among the stars, making them difficult to observe due to the Sun's brightness

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 21/12/2024

It's Winter Solstice! Earth's 23.4° tilt and position in orbit mean the northern hemisphere gets the fewest daylight hours under the least intense sunlight of the year. Today, Earth is on the left of the video below!

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 14/12/2024

It's a good time to see Jupiter next to the Moon this evening, in fact, even my Ring doorbell security camera can pick it up!

Above houses a very bright patch is seen, this is the Moon. Next to it, a much smaller white blob, it is Jupiter.

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 29/11/2024

Yeah, I've got more older ones to share, but I'm excited to create more... this is a little model I have made over the last year, which allows me to show things like eclipses

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 28/11/2024

Here's what might have happened to Uranus to make it rotate on its side: an impact by a planetary-scale body! This is a simulation by Jacob Kegerris (Durham University)

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 28/11/2024

Alternatively, for dwarf planet Pluto lovers, here are the eight planets of our solar system, and some change 🔭 Added an additional dwarf planet, Ceres, which is in the asteroid belt, for symmetry... (there are many more still!)

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 26/11/2024

The skies above Keck are clear (see live images: mkwc.ifa.hawaii.edu/current/cams...)

Starry sky above telescopes. Milky way overhead

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 26/11/2024

We're now on Jupiter... here it is coming into view

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 26/11/2024

Live infrared image of SATURN from the 10-metre Keck telescope in Hawaii We are observing the auroras of Saturn in the northern and southern hemispheres 🪐🔭

Saturn in black and white. The rings are black with a white halo around, the planet is stripey and grey

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 23/11/2024

The planets orbit the Sun at different speeds, with the inner planets moving the fastest—they need to, to resist being pulled in by the Sun's gravity. Here's a side-by-side comparison (race?) of their velocities!

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 23/11/2024

The reasons why any illustration of the Solar System can only be partially accurate: this highlights the compromises an illustrator has to make to fit everything into view

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 20/11/2024

When I had to start making things like this, I knew it was time to leave X...

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 20/11/2024

I once opened up the famous Superman ('78) scene using video editing software. Superman appeared to travel 20% faster than light for 10 seconds at top speed. But, Earth rotated 1,800x faster than normal in the scene, suggesting it's a timelapse, so he 'only' reached 200 km/s (0.07% of light speed)

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 18/11/2024

What's a Sidereal day? Earth completes one full rotation relative to distant stars in 23 hours 56 minutes—this is a Sidereal Day. But, because of Earth's orbital motion, the Sun appears to shift position each day. To align with the Sun again, Earth needs an extra 4 mins, making a Solar Day 24 hours:

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 18/11/2024

These are the planets to scale not only in size, but also in their tilt and rotation speed. Pluto and Ceres (a couple of dwarf planets) are included whether you like them or not 🫣

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 18/11/2024

The rotation periods of the planets, side-by-side

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 17/11/2024

The rings are so bright and reflective, mainly owing to the fact they're almost entirely made of (water) ice, that they go over the detector's brightness limits, so they appear black in the middle. Moons going by are also very bright, and at 6:00am this is what they are/were:

A mesh sphere with rings around it, representing a schematic view of Saturn, with longitude and latitude lines marked. Moons Dione, Enceladus and Tethys are slightly below the rings in different places from left to right, represented as black dots.

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 17/11/2024

Saturn's rings are eroding away by raining into the planet. We are observing Saturn with the huge 10-meter Keck telescope next week to see how this erosion modifies the atmosphere and shortens the rings' remaining lifetime Here's some raw imagery taken last month of our infrared set-up!

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 17/11/2024

Allow me to introduce myself on here! I'm a planetary scientist/astronomer at the University of Reading (UK), researching Jupiter & Saturn. I've worked at JAXA, NASA, Boston Uni and Uni of Leicester. On the side, I create space animations to share the wonders of our corner of the universe, such as:

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Dr James O'Donoghue 🪐 @interplanetary.bsky.social · 14/11/2024

I became effectively inactive Twitter on a particular date some time ago. Apart from some brief sessions, I haven't really posted much of value there (mainly replies). In fact, I lost my spirit for posting anywhere. Shame on Voldemort for mucking up what was a passable platform years ago

A graph of weekly tweets as a function of time from the end of 2019 to present. A huge drop off in tweets from a usual of about 200 to a few per week occurs at the end of 2022 when Voldemort took over the platform

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