Ganymede from Juno

What does the largest moon in the Solar System look like? Jupiter’s moon Ganymede, larger than even Mercury and Pluto, has an icy surface speckled with bright young craters overlying a mixture of older, darker, more cratered terrain laced with grooves and ridges. The cause of the grooved terrain remains a topic of research, with a leading hypothesis relating it to shifting ice plates. Ganymede is thought to have an ocean layer that contains more water than Earth — and might contain life. Like Earth’s Moon, Ganymede keeps the same face towards its central planet, in this case Jupiter. The featured image was captured last week by NASA’s robotic Juno spacecraft as it passed only about 1000 kilometers above the immense moon. The close pass reduced Juno’s orbital period around Jupiter from 53 days to 43 days. Juno continues to study the giant planet’s high gravity, unusual magnetic field, and complex cloud structures. [via NASA]

Eclipse on the Water

Eclipses tend to come in pairs. Twice a year, during an eclipse season that lasts about 34 days, Sun, Moon, and Earth can nearly align. Then the full and new phases of the Moon separated by just over 14 days create a lunar and a solar eclipse. Often partial eclipses are part of any eclipse season. But sometimes the alignment at both new moon and full moon phases during a single eclipse season is close enough to produce a pair of both total (or a total and an annular) lunar and solar eclipses. For this eclipse season, the New Moon following the Full Moon’s total lunar eclipse on May 26 did produce an annular solar eclipse along its northerly shadow track. That eclipse is seen here in a partially eclipsed sunrise on June 10, photographed from a fishing pier in Stratford, Connecticut in the northeastern US. [via NASA]

Eclipse Flyby

On June 10 a New Moon passed in front of the Sun. In silhouette only two days after reaching apogee, the most distant point in its elliptical orbit, the Moon’s small apparent size helped create an annular solar eclipse. The brief but spectacular annular phase of the eclipse shows a bright solar disk as a ring of fire when viewed along its narrow, northerly shadow track across planet Earth. Cloudy early morning skies along the US east coast held gorgeous views of a partially eclipsed Sun though. Rising together Moon and Sun are captured in a sequence of consecutive frames near maximum eclipse in this digital composite, seen from Quincy Beach south of Boston, Massachusetts. The serendipitous sequence follows the undulating path of a bird in flight joining the Moon in silhouette with the rising Sun. [via NASA]

Circular Sun Halo

Want to see a ring around the Sun? It’s easy to do in daytime skies around the world. Created by randomly oriented ice crystals in thin high cirrus clouds, circular 22 degree halos are visible much more often than rainbows. This one was captured by smart phone photography on May 29 near Rome, Italy. Carefully blocking the Sun, for example with a finger tip, is usually all that it takes to reveal the common bright halo ring. The halo’s characteristic angular radius is about equal to the span of your hand, thumb to little finger, at the end of your outstretched arm. Want to see a ring of fire eclipse? That’s harder. The spectacular annular phase of today’s (June 10) solar eclipse, known as a ring of fire, is briefly visible only if you’re standing along the Moon’s narrow shadow track that passes over parts of northern Canada, Greenland, the Arctic, and eastern Russia. The solar eclipse is partial though, when seen from broader regions, including northern Asia, Europe, and parts of the US. [via NASA]

A Total Lunar Eclipse Corona

This moon appears multiply strange. This moon was a full moon, specifically called a Flower Moon at this time of the year. But that didn’t make it strange — full moons occur once a month (moon-th). This moon was a supermoon, meaning that it reached its full phase near its closest approach to the Earth in its slightly elliptical orbit. Somewhat strange, a supermoon appears a bit larger and brighter than the average full moon — and enables it to be called a Super Flower Moon.  This moon was undergoing a total lunar eclipse. An eclipsed moon can look quite strange, being dark, unevenly lit, and, frequently, red — sometimes called blood red. Therefore, this moon could be called a Super Flower Blood Moon. This moon was seen through thin clouds. These clouds created a faint corona around the moon, making it look not only strange, but colorful. This moon was imaged so deeply that the heart of the Milky Way galaxy, far in the background, was visible to its lower right. This moon, this shadow, this galaxy and these colors were all captured last month near Cassilis, NSW, Australia — with a single shot. (Merged later with two lower shots that better capture the Milky Way.) [via NASA]

A Face in the Clouds of Jupiter from Juno

What do you see in the clouds of Jupiter? On the largest scale, circling the planet, Jupiter has alternating light zones and reddish-brown belts. Rising zone gas, mostly hydrogen and helium, usually swirls around regions of high pressure. Conversely, falling belt gas usually whirls around regions of low pressure, like cyclones and hurricanes on Earth. Belt storms can form into large and long-lasting white ovals and elongated red spots. NASA’s robotic Juno spacecraft captured most of these cloud features in 2017 during perijove 6, its sixth pass over the giant planet in its looping 2-month orbit. But it is surely not these clouds themselves that draws your attention to the displayed image, but rather their arrangement. The face that stands out, nicknamed Jovey McJupiterFace, lasted perhaps a few weeks before the neighboring storm clouds rotated away. Juno has now completed 33 orbits around Jupiter and just yesterday made a close pass near Ganymede, our Solar System’s largest moon. [via NASA]

A Bright Nova in Cassiopeia

What’s that new spot of light in Cassiopeia? A nova. Although novas occur frequently throughout the universe, this nova, known as Nova Cas 2021 or V1405 Cas, became so unusually bright in the skies of Earth last month that it was visible to the unaided eye. Nova Cas 2021 first brightened in mid-March but then, unexpectedly, became even brighter in mid-May and remained quite bright for about a week. The nova then faded back to early-May levels, but now is slightly brightening again and remains visible through binoculars. Identified by the arrow, the nova occurred toward the constellation of Cassiopeia, not far from the Bubble Nebula. A nova is typically caused by a thermonuclear explosion on the surface of a white dwarf star that is accreting matter from a binary-star companion — although details of this outburst are currently unknown. Novas don’t destroy the underlying star, and are sometimes seen to recur. The featured image was created from 14 hours of imaging from Detroit, Michigan, USA. Both professional and amateur astronomers will likely continue to monitor Nova Cas 2021 and hypothesize about details of its cause. [via NASA]

A Distorted Sunrise Eclipse

Yes, but have you ever seen a sunrise like this? Here, after initial cloudiness, the Sun appeared to rise in two pieces and during partial eclipse, causing the photographer to describe it as the most stunning sunrise of his life. The dark circle near the top of the atmospherically-reddened Sun is the Moon — but so is the dark peak just below it. This is because along the way, the Earth’s atmosphere had an inversion layer of unusually warm air which acted like a gigantic lens and created a second image. For a normal sunrise or sunset, this rare phenomenon of atmospheric optics is known as the Etruscan vase effect. The featured picture was captured in December 2019 from Al Wakrah, Qatar. Some observers in a narrow band of Earth to the east were able to see a full annular solar eclipse — where the Moon appears completely surrounded by the background Sun in a ring of fire. The next solar eclipse, also an annular eclipse for well-placed observers, will occur later this week on June 10. [via NASA]

The Shining Clouds of Mars

The weathered and layered face of Mount Mercou looms in the foreground of this mosaic from the Curiosity Mars rover’s Mast Camera. Made up of 21 individual images the scene was recorded just after sunset on March 19, the 3,063rd martian day of Curiosity’s on going exploration of the Red Planet. In the martian twilight high altitude clouds still shine above, reflecting the light from the Sun below the local horizon like the noctilucent clouds of planet Earth. Though water ice clouds drift through the thin martian atmosphere, these wispy clouds are also at extreme altitudes and could be composed of frozen carbon dioxide, crystals of dry ice. Curiosity’s Mast Cam has also imaged iridescent or mother of pearl clouds adding subtle colors to the martian sky. [via NASA]

Blood Monster Moon

On May 26, the Full Flower Moon was caught in this single exposure as it emerged from Earth’s shadow and morning twilight began to wash over the western sky. Posing close to the horizon near the end of totality, an eclipsed lunar disk is framed against bare oak trees at Pinnacles National Park in central California. The Earth’s shadow isn’t completely dark though. Faintly suffused with sunlight scattered by the atmosphere, the inner shadow gives the totally eclipsed moon a reddened appearance and the very dramatic popular moniker of a Blood Moon. Still, the monstrous visage of a gnarled tree in silhouette made this view of a total lunar eclipse even scarier. [via NASA]