Dr James O'Donoghue 🪐
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interplanetary.bsky.social
Dr James O'Donoghue 🪐
@interplanetary.bsky.social
Planetary scientist, astronomer and science communicator 🪐. Formerly at JAXA, NASA, Boston Uni, and the Uni of Leicester. Now Associate Professor at @UniofReading. Forbes 8 Billion Under 8 Billion. Website: odonoghuespace.github.io
Reposted by Dr James O'Donoghue 🪐
Most forecast centres (including us!) got that first CME arrival bang on. The big differences are for the subsequent CMEs.

SPWC predict >1400 km/s at Earth. HUXt around 850-950 km/s. It must be different assessments of the CME initial speeds; the models themselves aren't that different.
November 12, 2025 at 8:42 AM
Reposted by Dr James O'Donoghue 🪐
Wilhelm Röntgen discovered X-rays #OTD in 1895 when he noticed that emanations from a Crookes tube caused a platino-barium screen to fluoresce. The rays exposed photographic plates but were blocked by bone and metal.

This early plate shows his wife's hand. 🧪 ⚛️

Image: Wellcome Trust
November 8, 2025 at 5:07 PM
Reposted by Dr James O'Donoghue 🪐
Light speed is fast, but space is vast...
November 17, 2024 at 10:54 PM
Reposted by Dr James O'Donoghue 🪐
In somewhat terrifying but hopefully positive personal news, I've decided to purchase an extremely expensive 10x10 booth in the exhibit hall at the American Geophysical Union meeting in December. I'll be selling my gemstone and wire jewelry and art. I hope you'll come find me there.
October 23, 2025 at 5:41 PM
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:
October 22, 2025 at 5:57 PM
Reposted by Dr James O'Donoghue 🪐
This is what democracy looks like. #NoKings
October 18, 2025 at 11:22 PM
Reposted by Dr James O'Donoghue 🪐
Everyone writing about Perseverance today should be asking how many of the scientists and engineers who were involved in this discovery no longer work for NASA bc of Trump.
September 10, 2025 at 6:29 PM
Reposted by Dr James O'Donoghue 🪐
September 7, 2025 at 7:33 PM
Worst video ever, but go check out the lunar eclipse going on right now 🙂
September 7, 2025 at 7:17 PM
Reposted by Dr James O'Donoghue 🪐
Good luck UK Lunar Eclipse hunters. The Moon rises in the east in one hour!
September 7, 2025 at 5:31 PM
Join us for International Observe The Moon Night in-person (registration required) or online!🔭

Held and organized by the @uniofreading.bsky.social alongside Reading Astronomical Society, @royalastrosoc.bsky.social, Troodos Observatory (Cyprus) and supported by STFC
www.reading.ac.uk/news/2025/Un...
Observe the Moon Night University of Reading - University of Reading
www.reading.ac.uk
September 1, 2025 at 10:00 AM
Reposted by Dr James O'Donoghue 🪐
August 5 was a whole millisecond shorter. Strap in for the full explanation.
Why on Earth is the planet’s day getting shorter?
August 5 was a whole millisecond shorter. Strap in for the full explanation.
tcnv.link
August 5, 2025 at 2:47 PM
Reposted by Dr James O'Donoghue 🪐
Time nerds! This is def. one for you!

Today was/is one of the shortest days of the year.

@interplanetary.bsky.social has got you covered as to many of the reasons why this is likely happening.

Bonus - how quasars, and #RadioAstronomy lead to precision timing, orientation, etc. that gives us GPS!
August 5, 2025 at 1:34 PM
Reposted by Dr James O'Donoghue 🪐
💯.
August 4, 2025 at 5:21 PM
Reposted by Dr James O'Donoghue 🪐
Tiny black dot on Saturn. Early this morning, I photographed a rather rare astronomical event, a shadow transit of Saturn’s largest moon Titan across its parent planet. This is a composite of two frames. Questar telescope /Olympus camera. Observed from metro Chicago. #astrophotography
August 4, 2025 at 2:36 AM
Reposted by Dr James O'Donoghue 🪐
Our global petition to save NASA science closes this Thursday, and we’re just shy of 15,000 signatures! Every name counts, this petition will be hand-delivered to members of Congress. Add yours today, Save NASA Science.
planet.ly/petition
June 9, 2025 at 8:38 PM
Reposted by Dr James O'Donoghue 🪐
The auroral oval seen from space during the early morning on June 1 - captured by the NOAA-21 satellite flying over North America
June 1, 2025 at 5:00 PM
Reposted by Dr James O'Donoghue 🪐
Update on the ongoing geomagnetic storm: the main magnetic core of the 31 May #solarstorm has arrived at Earth starting around 1 June 12 UTC, BUT it is one of those kinds that are VERY unfavorable for #aurora - the field is entirely northward and very likely to remain so for the next few hours.
June 1, 2025 at 4:41 PM
Reposted by Dr James O'Donoghue 🪐
Looks like that fast CME is here already, about 2.5 hours before our predicted window.

Funnily enough, we've *just* worked out why fast CMEs are often earlier than predicted and will be rolling this into the forecast soon!

agupubs.onlinelibrary.wiley.com/doi/10.1029/...
Implications of Using Spheroidal “Cone Model” CMEs in Solar‐Wind Models
Slow spheroidal CMEs produce much longer transit times to 1 AU than observed Wide spheroidal CMEs produce much faster speeds at 1 AU than observed Fixed-duration CMEs, which mimic observed CME e...
agupubs.onlinelibrary.wiley.com
June 1, 2025 at 9:19 AM
Reposted by Dr James O'Donoghue 🪐
The WH proposes $6 billion cut in NASA budget, an overall 24% reduction from previous year – and a shocking 47% cut in funding for NASA’s Science Mission Directorate [reductions to to NASA’s fleet of spacecraft already in space, or proposed], an extinction-level event for the Earth & space sciences.
Proposed NASA cuts to space science: “Staggering”
earthsky.org
June 1, 2025 at 12:42 PM
Reposted by Dr James O'Donoghue 🪐
There's a fast CME heading into some fast solar wind and some pre-existing slower CMEs. We're currently putting arrival at noon-to-midnight tomorrow, but this forecast may change as more observations become available.

Updates here: research.reading.ac.uk/met-spate/hu...
May 31, 2025 at 7:04 AM
Reposted by Dr James O'Donoghue 🪐
Please, please, please contact your representatives. Jobs like mine are on the line. 🔭🧪☄️

www.planetary.org/save-nasa-sc...
May 30, 2025 at 11:06 PM
Reposted by Dr James O'Donoghue 🪐
BREAKING: The president's budget request just hit Congress, which could usher in a dark age for NASA space science.
Congress has the final say, but you can help shape the outcome by adding your name to our global petition.
This is just the start of our fight.
Sign the petition: planet.ly/petition
May 30, 2025 at 9:57 PM
Reposted by Dr James O'Donoghue 🪐
The NASA planetary science fleet chart if the president’s budget is enacted.
May 30, 2025 at 9:57 PM