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The month starts off with three bright planets clustered low in our east-southeast sky just before sunrise. Venus, Saturn and Mars are within six degrees of separation, but each morning thereafter the configuration noticeably changes. Mars and Saturn approach each other more closely than the apparent diameter of the moon on April 5. A view of the predawn sky on April 19, 2022 in Stellarium shows the alignment of Jupiter, Venus, Mars and Saturn. (Image credit: Stellarium) The main event comes during the final week of April with the approach of magnitude -2 Jupiter to magnitude -4 Venus, seven times...

Explanation: Why would the surface of Titan light up with a blinding flash? The reason: a sunglint from liquid seas. Saturn's moon Titan has numerous smooth lakes of methane that, when the angle is right, reflect sunlight as if they were mirrors. Pictured here in false-color, the robotic Cassini spacecraft that orbited Saturn from 2004 to 2017 imaged the cloud-covered Titan in 2014 in different bands of cloud-piercing infrared light. This specular reflection was so bright it saturated one of Cassini's infrared cameras. Although the sunglint was annoying -- it was also useful. The reflecting regions confirm that northern Titan...

Explanation: Seen from ice moon Tethys, rings and shadows would display fantastic views of the Saturnian system. Haven't dropped in on Tethys lately? Then this gorgeous ringscape from the Cassini spacecraft will have to do for now. Caught in sunlight just below and left of picture center in 2005, Tethys itself is about 1,000 kilometers in diameter and orbits not quite five saturn-radii from the center of the gas giant planet. At that distance (around 300,000 kilometers) it is well outside Saturn's main bright rings, but Tethys is still one of five major moons that find themselves within the boundaries...

Jupiter, Saturn and Venus have lined up in the evening sky and will continue to be prominent features throughout most of December, but this week, the trio will get a visitor. The easy-to-find planets, paired with the approaching peak of the Geminid meteor shower, make December a great month for evening stargazing. The only caveat is that the weather can be fickle during the long December nights, often offering frosty conditions on nights that are not cloudy. The moon started off the week next to Venus, and as the week progresses, it will continue to move up the chain, passing...

Composite image of Neptune, Uranus, Saturn and Jupiter. Credit: Jupiter from Juno: NASA/SwRI/MSSS/Gerald Eichstädt/Seán Doran; Saturn from Cassini: NASA/JPL-Caltech/Space Science Institute; Uranus and Neptune from HST: NASA/ESA/A. Simon (NASA Goddard Space Flight Center), and M.H. Wong and A. Hsu (University of California, Berkeley). ========================================================================================== Mushballs – giant, slushy hailstones made from a mixture of ammonia and water – may be responsible for an atmospheric anomaly at Neptune and Uranus that has been puzzling scientists. A study presented by Tristan Guillot at the Europlanet Science Congress (EPSC) 2021 shows that mushballs could be highly effective at carrying ammonia deep into the...

Spotting Jupiter is a breeze this week for the naked eye as it reaches its biggest and brightest moment in the night sky. Telescope-hunters will also get a treat looking for moons and atmospheric bands. The gas giant planet will be at opposition today (Aug. 19), meaning it is directly opposite the sun in Earth's sky. Jupiter also makes its closest approach of the year to Earth during opposition. The planet will appear at magnitude -2.9, well within naked-eye range and outshining any star in Earth's sky except, of course, for the sun. To spot Jupiter, look to the left...

Now might be the time to wipe the dust off that pair of binoculars and extract the family telescope from the back of the closet: Saturn is about to put on its best and brightest show, looking spiffier than at any time during the year – a performance that will be followed a few weeks later by Jupiter. The ringed planet will be at opposition on Sunday for people in North America. What exactly does that mean? Imagine Earth and Saturn are hands on a clock face, says Phil Plait, an astronomer and longtime science educator. "So very roughly once...

Explanation: What drives auroras on Saturn? To help find out, scientists have sorted through hundreds of infrared images of Saturn taken by the Cassini spacecraft for other purposes, trying to find enough aurora images to correlate changes and make movies. Once made, some movies clearly show that Saturnian auroras can change not only with the angle of the Sun, but also as the planet rotates. Furthermore, some auroral changes appear related to waves in Saturn's magnetosphere likely caused by Saturn's moons. Pictured here, a false-colored image taken in 2007 shows Saturn in three bands of infrared light. The rings reflect...

Explanation: Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest round moons. Analysis indicates that a slightly larger impact would have destroyed Mimas entirely. The huge crater, named Herschel after the 1789 discoverer of Mimas, Sir William Herschel, spans about 130 kilometers and is featured here. Mimas' low mass produces a surface gravity just strong enough to create a spherical body but weak enough to allow such relatively large surface features. Mimas is made of mostly water ice with a smattering of rock - so it is accurately described...

The path of true love never runs smooth, it is said. Especially on Valentine's Day. And for young planets, that path turns out to be an inward-moving annulus. A simulation by scientists in France and USA appears to show that Jupiter once strayed to flirt with the inner Solar System, before being "jilted" and sent back to its present-day position. The effect of this was to form the inner planets, according to the theory, which comes up with mass ratios for Earth and Mars similar to that observed today and which, remarkably, also accurately depicts the Asteroid Belt. If the...

As the solar system was developing, the giant planets (Jupiter and Saturn) formed very early, and as they grew, they migrated both closer to and further away from the sun to stay in gravitationally stable orbits. The gravitational effect of these massive objects caused immense reshuffling of other planetary bodies that were forming at the time, meaning that the current locations of many planetary bodies in our solar system are not where they originally formed. Lawrence Livermore National Laboratory (LLNL) scientists set out to reconstruct these original formation locations by studying the isotopic compositions of different groups of meteorites that...

Explanation: Why does a cloudy moon sometimes appear colorful? The effect, called a lunar corona, is created by the quantum mechanical diffraction of light around individual, similarly-sized water droplets in an intervening but mostly-transparent cloud. Since light of different colors has different wavelengths, each color diffracts differently. Lunar Coronae are one of the few quantum mechanical color effects that can be easily seen with the unaided eye. Solar coronae are also sometimes evident. The featured composite image was captured a few days before the close Great Conjunction between Saturn and Jupiter last month. In the foreground, the Italian village of...

From Jan. 9-12, Mercury, Jupiter, and Saturn will be visible in the southwestern sky. The celestial event is known as a “triple conjunction,” which means two planets and a third planet meet each other in the sky for a short period of time. Shortly after sunset on Jan. 9, look above the west-southwestern horizon and you will see Mercury to the left of Saturn and Jupiter positioned just above Saturn. “From Friday evening to Monday evening, the planet Mercury will appear to pass first by Saturn and then by Jupiter as it shifts away from the horizon, visible each evening...

Today's image is a video at link. Explanation: Yes, but have you seen a movie of Jupiter and Saturn's Great Conjunction? The featured time-lapse video was composed from a series of images taken from Thailand and shows the two giant planets as they angularly passed about a tenth of a degree from each other. The first Great Conjunction sequence shows a relative close up over five days with moons and cloud bands easily visible, followed by a second video sequence, zoomed out, over 9 days. Even though Jupiter and Saturn appeared to pass unusually close together on the sky on...

Explanation: It was time for their close-up. Two days ago Jupiter and Saturn passed a tenth of a degree from each other in what is known a Great Conjunction. Although the two planets pass each other on the sky every 20 years, this was the closest pass in nearly four centuries. Taken early in day of the Great Conjunction, the featured multiple-exposure combination captures not only both giant planets in a single frame, but also Jupiter's four largest moons (left to right) Callisto, Ganymede, Io, and Europa -- and Saturn's largest moon Titan. If you look very closely, the clear...

THE GREAT CONJUNCTION OF JUPITER AND SATURN: Want to see something that astronomers have been waiting 800 years to witness? Just step outside at sunset and look southwest. Jupiter and Saturn are having their finest conjunction since the Middle Ages--and they're bright. Bertrand Kulik sends this picture from Paris:"On Dec. 20th, the planets were visible right beside the Eiffel Tower," says Kulik. "It was a magical view!" At closest approach on Dec. 21st, the two planets will lie just 0.1 degrees apart. That’s so close, some people will perceive them as a single brilliant star. Viewed through binoculars or a...

FRIDAY, DECEMBER 4 [basically the same as today (Sunday), tomorrow, and next few days] Bright Jupiter and Saturn are closer together now (1.8° apart).Jupiter and Saturn are closing toward their record-breaking conjunction on December 21st, when they will appear only 0.1° apart. That’s about the width of a toothpick at arm’s length!https://skyandtelescope.org/observing/this-weeks-sky-at-a-glance-december-4-12-2/

The first image below is pretty much the situation in the night sky now, Nov 25, 2020. Little by little, Jupiter, from our perspective, is inching closer and closer to Saturn. And by mid-December the two planets will appear to be practically on top of each other, I think both within the space of a full moon! The 2nd image below is the situation in mid-December (this is NOT a one-day, or even one week, thing).In fact the two planets are fairly close to each other right now, Nov 25 (first image below).But in reality, Saturn is actually something like...

Just after sunset on the evening of December 21, 2020, Jupiter and Saturn will appear closer together in Earth’s night sky than they have been since the Middle Ages, offering people the world over a celestial treat to ring in the winter solstice. Jupiter and Saturn have been approaching one another in Earth’s sky since the summer. From December 16-25, the two will be separated by less than the diameter of a full moon. Though the best viewing conditions will be near the equator, the event will be observable anywhere on Earth, weather-permitting. Hartigan said the planetary duo will appear...

Mercury will likely be the hardest planet to spot, and binoculars would help. First, look for Venus. Venus is still the brightest of the planets and the third brightest celestial object, only behind the sun and the moon. Venus will be easy to find in the east before and during dawn. Once you’ve located Venus, look beneath it toward the horizon. Mercury will be low in the east-southeast about an hour before sunrise. Mars, Jupiter and Saturn will be visible in the evening. Mars is getting less bright by the day, but it will still be easy to find in...