Not to mention the first images of the Galilean moons as something other than dots.

Pioneer launched as low-cost pathfinders to test the asteroid belt & Jupiter’s radiation before the Voyager “Grand Tour” missions. On board: magnetometer, plasma analyser, cosmic-ray telescope, UV/IR photometers, trapped-radiation detector,Imaging Photopolarimeter. #AstroHistory

1973-74: Pioneer 10 & 11 deliver the first close-up colour views of Jupiter. The probes had no true camera, just a spinning Imaging Photopolarimeter scanning through red and blue filters. Images: Pioneer 10 montage, Dec 1973 Pioneer 11 full-disk from 760,000 km, Dec 1974 #AstroHistory #Jupiter

Friday I plan to release an update to skycalpro. This release is the Jupiter Great Red Spot update skycalpro.com

In 1892 E.E. Barnard discovered Jupiter's 5th moon, Amalthea, the last moon found by eye through a telescope. Over the next 80 years photos were B&W, and improved only a little over the period. 1891 Lick Obs-36" refractor, E.E. Barnard 1950 Mt Palomar-200" reflector, M.L. Humason #AstroHistory

Sky at Night always used to have an early repeat - and we're back, with our collaboration with the Curious Cases team on at 7pm tomorrow on BBC4. Please watch if you possibly can - support your local science program! www.bbc.co.uk/programmes/m...

In 1892 E.E. Barnard discovered Jupiter's 5th moon, Amalthea, the last moon found by eye through a telescope. Over the next 80 years photos were B&W, and improved only a little over the period. 1891 Lick Obs-36" refractor, E.E. Barnard 1950 Mt Palomar-200" reflector, M.L. Humason #AstroHistory

#GoodMorningEveryone and enjoy the Waning Gibbous phase #moonphase of our satellite, the Moon, as it crosses the Leo constellation, 379,000 km above us. Yes, all of us, no matter where we live on this planet. The sky above us is for all of us, free-of-charge, and unlimited. 😉

Since I recently retired, I can gleefully work all day figuring and testing my 62 cm (24 inch) cellular primary mirror. Having produced a good spheroidal figure, it's finally ready to parabolize. Amazingly, this is Norway's largest optical telescope. 🔭

Been a poor show with my photography recently. I didn't enter the last club PDI competition (I run them so that's bad form!). I hardly used my camera last year. But I did take some pics in London recently. My Open Colour PDI entries: 'Tulip Staircase' and 'Salmon & Lime'

Oh well, it's only takes years of trial and error studying various techniques and inhuman quantities of patience. Here's 2000 hours compressed to 30 seconds. 24 inch (62 cm) diameter f/3.4 paraboloid primary mirror.

While Andrew Ainslie Common was pioneering Jupiter photography, French artist-astronomer Étienne Léopold Trouvelot captured what he saw through Harvard’s 15-inch Merz refractor. Drawn Nov 1 1880 (9:30 PM); published 1881 in The Trouvelot Astronomical Drawings. #AstroHistory #Jupiter

After a lot of faffing this week, early this morning, I managed to stage the changes to the GRS calculation on SkyCalPro. That's a big step. When i get time this week I'll mock it up in production and see if it goes up there too. Hopefully ready publicly in the next couple of days #AstroMethods

Thanks everyone for all your likes, follows comments and questions this week. Particularly on my history of Jupiter series! You are awesome!

While Andrew Ainslie Common was pioneering Jupiter photography, French artist-astronomer Étienne Léopold Trouvelot captured what he saw through Harvard’s 15-inch Merz refractor. Drawn Nov 1 1880 (9:30 PM); published 1881 in The Trouvelot Astronomical Drawings. #AstroHistory #Jupiter

The first surviving successful image of Jupiter was taken in 1879 by Andrew Ainslie Common in Ealing, London, using his 36-inch Newtonian reflector and the wet collodion process invented in 1851 by portrait photographer Frederick Scott Archer

I’m going to have an educated guess at the moon image: I think we’re looking at a half moon (white circle with terminator black line), exposed that the earthshine is showing on the right. The purple circle is the scope aperture. The bubbles artefacts of the development process. What do you think?

Fireworks at Clacton Pier last night. “Remember Remember the 5th November”. Where we remember that in 1605, Guy Fawkes tried to blow up the houses of parliament. He wanted to kill the King, Lords and MP’s, trigger an uprising and place a young Princess Elizabeth on the throne

My walk right now #MoonHour

Leaping on several hundred years, my next people are: Louis Daguerre: Creator of Daguerreotype technique and took the first photo of a human John Draper: Used Daguerre's technique, a daguerreotype plate and a 5-inch reflector telescope to capture the Moon—paving the way for astrophotography

Sunset just now #Sunset

Earth and its moon are framed in this image taken from the aft windows of the Space Shuttle Discovery in 1998. Discovery mission STS-95 was flying over the Atlantic Ocean when this image was taken. The STS-95 mission also marked the return of U.S. Senator John Glenn to space. Image credit: NASA

In 1668 Isaac Newton built the first reflecting telescope, inspired by his prism experiments on light and colour; he solved the chromatic blur in glass lenses. Using Cassini and Flamsteed’s observations of Jupiter’s moons (1687), he proved his law of universal gravitation held true. #AstroHistory

The #BeaverMoon — #Supermoon — over Orlando. I was happy I could capture this. I used my #Celestron NexStar 8SE #telescope and #Canon camera. (The photo of the moon over #Orlando is a composite and whatnot.) #astronomy #astrophotography #moon #FullMoon

That is an amazing capture! That is more detailed than what I got of Io earlier this year. And I love the facts you shared.

Earth and its moon are framed in this image taken from the aft windows of the Space Shuttle Discovery in 1998. Discovery mission STS-95 was flying over the Atlantic Ocean when this image was taken. The STS-95 mission also marked the return of U.S. Senator John Glenn to space. Image credit: NASA

In 1668 Isaac Newton built the first reflecting telescope, inspired by his prism experiments on light and colour; he solved the chromatic blur in glass lenses. Using Cassini and Flamsteed’s observations of Jupiter’s moons (1687), he proved his law of universal gravitation held true. #AstroHistory

Sunset this evening was stunning. One from the top road at Aylmerton & down to Sheringham sea front where the sea was just glowing pink 🥰 #CoastLife #Sunset @chrisdoward.bsky.social @chrispage90.bsky.social @christhomson.bsky.social @skycalpro.com @virtualastro.bsky.social

This JSWT image shows Jupiter's Ring. Also you can see Jupiter's Great Red Spot (GRS), Jupiter's large moon Europa (the diffraction spikes) on the left, and Europa's shadow (next to the GRS). The seemingly separated cloud layer on Jupiter's right limb are not yet well understood. #Astronomy #Jupiter

In 1676 Ole Rømer saw eclipses of Jupiter’s moon Io run late when Earth moved away from Jupiter and early when approaching. Earth’s orbital diameter was known from Kepler’s laws; from this he was the first to estimate the speed of light (at 220,000 km/s) and was accurate to 75% #AstroHistory

Sunset just now

My favourite region on the #moon, Mare Imbrum, with adjacent craters Sinus Iridum, Plato and Copernicus. In this moon phase, special tectonic features, so-called wrinkles are visible on the floor of Mare Imbrum, inter alia Dorsum Heim and Dorsum Zirkel Skymax102, ASI 220 Mini Mono 🔭 #astrophoto

This JSWT image shows Jupiter's Ring. Also you can see Jupiter's Great Red Spot (GRS), Jupiter's large moon Europa (the diffraction spikes) on the left, and Europa's shadow (next to the GRS). The seemingly separated cloud layer on Jupiter's right limb are not yet well understood. #Astronomy #Jupiter

If you like visualisations on how Romer calculated the speed of light, this software is a nice resource. A few steps to install and use, but it's all there. Thanks @finitemonkey.bsky.social for the tip!

In 1676 Ole Rømer saw eclipses of Jupiter’s moon Io run late when Earth moved away from Jupiter and early when approaching. Earth’s orbital diameter was known from Kepler’s laws; from this he was the first to estimate the speed of light (at 220,000 km/s) and was accurate to 75% #AstroHistory

Tomorrow I continue the history of Jupiter with how it was used to accurately measure the speed of light (250 years ago)! Sadly no drawings tomorrow, my next person's drawings, notes and equipment were all destroyed....

On June 3, 1965, Edward H. White II became the first American to step outside his spacecraft and let go, effectively setting himself adrift in the zero gravity of space. For 23 minutes he floated and maneuvered himself around the Gemini spacecraft while logging 6,500 miles during his orbital stroll.

In 1665, Giovanni Cassini was first to observe a “Permanent Spot” on Jupiter, though probably wasn't today’s Red Spot using 34-ft refractors at the Paris Observatory. He tracked it for years to measure Jupiter’s rotation. Cassini’s drawings survive in Paris Observatory archives. #AstroHistory

On June 3, 1965, Edward H. White II became the first American to step outside his spacecraft and let go, effectively setting himself adrift in the zero gravity of space. For 23 minutes he floated and maneuvered himself around the Gemini spacecraft while logging 6,500 miles during his orbital stroll.

In 1665, Giovanni Cassini was first to observe a “Permanent Spot” on Jupiter, though probably wasn't today’s Red Spot using 34-ft refractors at the Paris Observatory. He tracked it for years to measure Jupiter’s rotation. Cassini’s drawings survive in Paris Observatory archives. #AstroHistory

Rocket launch in less than two hours: Ariane 6 (Arianespace): Sentinel-1D Mission, Launching a radar satellite into a Sun-Synchronous Orbit to provide weather updates day and night ESA are live streaming - Remember that skycalpro.com lists all upcoming launches and links to live video if available!

Galileo's O and * drawing of Jupiter and it's moons aren't so impressive given the likes, but it's Monday so I'll forgive! I'm going to stick with Jupiter history for this week. Tomorrow is Cassini. He used Kepler optics 🔭 and his drawings of Jupiter were much better! Image credit: JPL/NASA/STScI

Thanks again for all the likes and retweets. My Voyager II and Isaac Roberts tweets seem popular, so I'm going to each day this week with a little history of Jupiter. Hopefully by the end of the week I'll have finished testing the next release of skycalpro.com (Jupiter GRS) #AstroHistory

This is Jupiter recorded by Voyager 1 in 1979. Note the difference in speed & direction of the zones of the atmosphere. This turbulence is erratic and makes it hard to predict when the red spot will appear over a period time. Named Blue Movie as it was built from blue filter images. #Astronomy

What would Galileo say, from his prison cell?

The Solid State Imaging (CCD) system aboard NASA's Galileo spacecraft obtained the Jupiter, Io and Ganymede images in June 1996, while the Europa images were obtained in September 1996. The portrait of Callisto is from the 1979 flyby of NASA's Voyager spacecraft. #Jupiter #Astronomy

Galileo made his own telescopes, and two originals survive at the Museo Galileo, Florence. One (1609) has a 37 mm lens stopped to 15 mm, 980 mm focal length, 21× mag; the other (1610) a 51 mm lens, 1330 mm focal length, 14×. His 1610 book Sidereus Nuncius is also preserved there. #Astronomy #Jupiter

In 1610, Galileo and Simon Marius first saw Jupiter’s moons. Galileo is credited with the discovery as he published first. The sketches below are from his book. Galileo tried to argue that Earth circles the Sun, but under threat of torture was forced to renounce the idea #AstroHistory #Jupiter

I wish Bluesky had an edit button. I can read my own post 20 times and still not see that I missed a word out. Been the same my whole life! I just don’t see it! I love passing on information, but writing isn’t my favourite way to do it!

It's not the best image you are going to see of Comet C/2025 A6 (Lemmon), but I managed to catch it with my DSLR. 30 images stacked. 5 seconds/ISO 800/ F/3.5. A quick set up with the intervalometer, just after sunset. I'm quite pleased to have caught it! #Astrophotography #Astronomy