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This Star Wars: Black Series Force Elite Sabine Wren Lightsaber is 34% off at Amazon, just what I need to tide me over till Star Wars: Ahsoka Season 2.

Robotic equipment can implant electrodes into cockroaches and connect them to an electronic backpack, making it feasible to mass-produce biorobots for search missions

Robotic equipment can implant electrodes into cockroaches and connect them to an electronic backpack, making it feasible to mass-produce biorobots for search missions

New modeling research reveals that the Atlantic Meridional Overturning Circulation (AMOC) is particularly vulnerable to shifts in the Irminger sea off Greenland from increasing Arctic meltwater.

Image: BepiColombo's fifth Mercury flyby

This sleek MacBook Air M3 13-inch laptop, ideal for budding astronomers, is an absolute steal at 23% in Amazon's Black Friday sale.

The Copernicus Sentinel-1C satellite is ready for liftoff! Tune in to ESA WebTV on 4 December from 22:00 CET to watch the satellite soar into space on a Vega-C rocket to be launched from Europe’s Spaceport in Kourou, French Guiana. Sentinel-1C is scheduled to liftoff at 22:20 CET.

Week in images: 25-29 November 2024

Discover our week through the lens

Physicists have described a system that requires an incomputable number to fully understand, another example of the provably unprovable puzzles of mathematics

The bacteria could be grown in space, and lend their photosynthesizing talents to supplying power to the hundreds of thousands of satellites in orbit.

You can save up to 40% on Lego Star Wars sets thanks to Lego's Black Friday sale, and claim some free gifts alongside your purchases.

I love sci-fi and I would get the Disney Plus and Hulu bundle, which is 72% off for Black Friday, if I didn't already have a subscription.

In difficult times, a forward-looking mindset may be especially helpful

This magnificent Celestron NexStar Evolution 8, with a computerized star-tracking mount, is an amazing $450 off in Adorama's Black Friday sale

The ocean’s digestive system is dictated by picky microbes and precise dynamics of drifting debris

“Twilight rays” are but one of several viewing treats for the liminal time between day and night

The Acidalia Planitia region of the Red Planet might have all the requirements for methane-burping bacteria to exist beneath the surface

The Acidalia Planitia region of the Red Planet might have all the requirements for methane-burping bacteria to exist beneath the surface

4 min read

December’s Night Sky Notes: Spot the King of Planets

by Kat Troche of the Astronomical Society of the Pacific

Jupiter is our solar system’s undisputed king of the planets! Jupiter is bright and easy to spot from our vantage point on Earth, helped by its massive size and banded, reflective cloud tops. Jupiter even possesses moons the size of planets: Ganymede, its largest, is bigger than the planet Mercury. What’s more, you can easily observe Jupiter and its moons with a modest instrument, just like Galileo did over 400 years ago.

This image taken on Feb. 7 by NASA’s Juno spacecraft, reveals swirling cloud formations in the northern area of Jupiter’s north temperate belt. Citizen scientist Kevin M. Gill processed the image using data from the JunoCam imager. NASA, JPL-Caltech, SwRI, MSSS | Image processing by Kevin M. Gill, © CC BY

Jupiter’s position as our solar system’s largest planet is truly earned; you could fit 11 Earths along Jupiter’s diameter, and in case you were looking to fill up Jupiter with some Earth-size marbles, you would need over 1300 Earths to fill it up – and that would still not be quite enough! However, despite its formidable size, Jupiter’s true rule over the outer solar system comes from its enormous mass. If you took all of the planets in our solar system and put them together, they would still only be half as massive as Jupiter all by itself. Jupiter’s mighty mass has shaped the orbits of countless comets and asteroids. Its gravity can fling these tiny objects towards our inner solar system and also draw them into itself, as famously observed in 1994 when Comet Shoemaker-Levy 9, drawn towards Jupiter in previous orbits, smashed into the gas giant’s atmosphere. Its multiple fragments slammed into Jupiter’s cloud tops with such violence that the fireballs and dark impact spots were not only seen by NASA’s orbiting Galileo probe but also by observers back on Earth! 

Look for Jupiter near the Eye of the Bull, Aldebaran, in the Taurus constellation on the evening of December 15, 2024. Binoculars may help you spot Jupiter’s moons as small bright star-like objects on either side of the planet. A small telescope will show them easily, along with Jupiter’s famed cloud bands. How many can you count? Credit: Stellarium Web

Jupiter is easy to observe at night with our unaided eyes, as well-documented by the ancient astronomers who carefully recorded its slow movements from night to night. It can be one of the brightest objects in our nighttime skies, bested only by the Moon, Venus, and occasionally Mars, when the red planet is at opposition. That’s impressive for a planet that, at its closest to Earth, is still over 365 million miles (587 million km) away. It’s even more impressive that the giant world remains very bright to Earthbound observers at its furthest distance: 600 million miles (968 million km)! While the King of Planets has a coterie of 95 known moons, only the four large moons that Galileo originally observed in 1610 – Io, Europa, Ganymede, and Calisto – can be easily observed by Earth-based observers with very modest equipment. These are called, appropriately enough, the Galilean moons. Most telescopes will show the moons as faint star-like objects neatly lined up close to bright Jupiter. Most binoculars will show at least one or two moons orbiting the planet. Small telescopes will show all four of the Galilean moons if they are all visible, but sometimes they can pass behind or in front of Jupiter or even each other. Telescopes will also show details like Jupiter’s cloud bands and, if powerful enough, large storms like its famous Great Red Spot, and the shadows of the Galilean moons passing between the Sun and Jupiter. Sketching the positions of Jupiter’s moons during the course of an evening – and night to night – can be a rewarding project! You can download an activity guide from the Astronomical Society of the Pacific at bit.ly/drawjupitermoons

Now in its eighth year, NASA’s Juno mission is one of just nine spacecraft to have visited this impressive world. Juno entered Jupiter’s orbit in 2016 to begin its initial mission to study this giant world’s mysterious interior. The years have proven Juno’s mission a success, with data from the probe revolutionizing our understanding of this gassy world’s guts. Juno’s mission has since been extended to include the study of its large moons, and since 2021 the plucky probe, increasingly battered by Jupiter’s powerful radiation belts, has made close flybys of the icy moons Ganymede and Europa, along with volcanic Io. What else will we potentially learn in 2030 with the Europa Clipper mission? 

Find the latest discoveries from Juno and NASA’s missions to Jupiter at science.nasa.gov/jupiter/

Originally posted by Dave Prosper: February 2023
Last Updated by Kat Troche: November 2024

Image: A colourful patchwork of agricultural fields is pictured in this radar image captured by Copernicus Sentinel-1 over southeastern Romania.