It was one of the largest and longest lived storms ever recorded in our Solar System. First seen in late 2010, the above cloud formation in the northern hemisphere of Saturn started larger than the Earth and soon spread completely around the planet. The storm was tracked not only from Earth but from up close by the robotic Cassini spacecraft then orbiting Saturn. Pictured here in false colored infrared in February, orange colors indicate clouds deep in the atmosphere, while light colors highlight clouds higher up. The rings of Saturn are seen nearly edge-on as the thin blue horizontal line. The warped dark bands are the shadows of the rings cast onto the cloud tops by the Sun to the upper left. A source of radio noise from lightning, the intense storm was thought to relate to seasonal changes when spring emerges in the north of Saturn. After raging for over six months, the iconic storm circled the entire planet and then tried to absorb its own tail — which surprisingly caused it to fade away.
Of course this little planet is really planet Earth in a digitally stitched 360 x 180 degree mosaic captured high in the Chilean Atacama desert.
Famed in festival, story, and song the best known full moon is the Harvest Moon. For northern hemisphere dwellers that’s a traditional name of the closest full moon to the September equinox. In most North America time zones this year’s Harvest Moon will officially rise on Friday, September 13. In fact the same Harvest Moon will rise on September 14 for much of the planet though. Of course the Moon will look almost full in the surrounding days. Regardless of your time zone the Harvest Moon, like any other full moon, will rise just opposite the setting Sun. Near the horizon, the Moon Illusion might make it appear bigger and brighter to you but this Harvest Moon will be near lunar apogee. That’s the farthest point in its orbit, making it the most distant, and so the smallest, full moon of the year. On August 15 a wheat field harvested in south central France made this a harvest moon scene too, the full moon shining on with beautiful iridescent clouds at sunset.
These cosmic dust clouds drift some 1,300 light-years away along the fertile starfields of the constellation Cepheus. The beautiful Iris Nebula, also known as NGC 7023, blossoms at the upper left. Not the only nebula in the sky to evoke the imagery of flowers, its pretty, symmetric form spans about 6 light-years. This nebula’s dominant blue color is characteristic of the pervasive dust grains reflecting light from a nearby hot, bluish star. But darker, obscuring dust clouds cover most of the nearly 4 degree wide field of view. At the right is the LDN 1147/1158 complex of Lynds Dark Nebulae. Stars are forming there, still hidden within the dark cloud cores. A search through the sharp image can identify Herbig-Haro objects though, jets of shocked glowing gas emanating from recently formed stars.
What energizes the Heart Nebula? First, the large emission nebula dubbed IC 1805 looks, in whole, like a human heart. The nebula glows brightly in red light emitted by its most prominent element: hydrogen. The red glow and the larger shape are all powered by a small group of stars near the nebula’s center. In the center of the Heart Nebula are young stars from the open star cluster Melotte 15 that are eroding away several picturesque dust pillars with their energetic light and winds. The open cluster of stars contains a few bright stars nearly 50 times the mass of our Sun, many dim stars only a fraction of the mass of our Sun, and an absent microquasar that was expelled millions of years ago. The Heart Nebula is located about 7,500 light years away toward the constellation of Cassiopeia. Coincidentally, a small meteor was captured in the foreground during imaging and is visible above the dust pillars. At the top right is the companion Fishhead Nebula.
What color is Pluto, really? It took some effort to figure out. Even given all of the images sent back to Earth when the robotic New Horizons spacecraft sped past Pluto in 2015, processing these multi-spectral frames to approximate what the human eye would see was challenging. The result featured here, released three years after the raw data was acquired by New Horizons, is the highest resolution true color image of Pluto ever taken. Visible in the image is the light-colored, heart-shaped, Tombaugh Regio, with the unexpectedly smooth Sputnik Planitia, made of frozen nitrogen, filling its western lobe. New Horizons found the dwarf-planet to have a surprisingly complex surface composed of many regions having perceptibly different hues. In total, though, Pluto is mostly brown, with much of its muted color originating from small amounts of surface methane energized by ultraviolet light from the Sun.