What strange world is this? Earth. In the foreground of the featured image are the Pinnacles, unusual rock spires in Nambung National Park in Western Australia. Made of ancient sea shells (limestone), how these human-sized picturesque spires formed remains unknown. In the background, just past the end of the central Pinnacle, is a bright crescent Moon. The eerie glow around the Moon is mostly zodiacal light, sunlight reflected by dust grains orbiting between the planets in the Solar System. Arching across the top is the central band of our Milky Way Galaxy. Many famous stars and nebulas are also visible in the background night sky. The featured 29-panel panorama was taken and composed in 2015 September after detailed planning that involved the Moon, the rock spires, and their corresponding shadows. Even so, the strong zodiacal light was a pleasant surprise. via NASA https://ift.tt/36Pnt13

Galaxies of the Virgo Cluster are scattered across this deep telescopic field of view. The cosmic scene spans about three Full Moons, captured in dark skies near Jalisco, Mexico, planet Earth. About 50 million light-years distant, the Virgo Cluster is the closest large galaxy cluster to our own local galaxy group. Prominent here are Virgo’s bright elliptical galaxies from the Messier catalog, M87 at the top left, and M84 and M86 seen (bottom to top) below and right of center. M84 and M86 are recognized as part of Markarian’s Chain, a visually striking line-up of galaxies vertically on the right side of this frame. Near the middle of the chain lies an intriguing interacting pair of galaxies, NGC 4438 and NGC 4435, known to some as Markarian’s Eyes. Of course giant elliptical galaxy M87 dominates the Virgo cluster. It’s the home of a super massive black hole, the first black hole ever imaged by planet Earth’s Event Horizon Telescope. via NASA https://ift.tt/3iJGfcf

An inspirational sight, these giant dish antennas of the Karl G. Jansky Very Large Array (VLA) rise above the New Mexico desert at moonset. Mounted on piers but transportable on railroad tracks to change the VLA’s configuration, its 27 operating antennas are each house-sized (25 meters across) and can be organized into an array spanning the size of a city (35 kilometers). A prolific radio astronomy workhorse, the VLA has been used to discover water on planet Mercury, radio-bright coronae around stars, micro-quasars in our Galaxy, gravitationally-induced Einstein rings around distant galaxies, and radio counterparts to cosmologically distant gamma-ray bursts. Its vast size has allowed astronomers to study the details of radio galaxies, super-fast cosmic jets, and map the center of our own Milky Way. Now 40 years since its dedication the VLA has been used in more than 14,000 observing projects and contributed to more than 500 Ph.D. dissertations. On October 10, the National Radio Astronomy Observatory will host a day-long online celebration of the VLA at 40 featuring virtual tours and presentations on the history, operations, science, and future of the Very Large Array. via NASA https://ift.tt/33GEd8v

Lighter than typically dark, smooth, mare the Mare Frigoris lies in the far lunar north. Also known as the Sea of Cold, it stretches across the familiar lunar nearside in this close up of the waxing gibbous Moon’s north polar region. Dark-floored, 95 kilometer wide crater Plato is just left of the center. Sunlit peaks of the lunar Alps (Montes Alpes) are highlighted below and right of Plato, between the more southern Mare Imbrium (Sea of Rains) and Mare Frigoris. The prominent straight feature cutting through the mountains is the lunar Alpine Valley (Vallis Alpes). Joining the Mare Imbrium and Mare Frigoris, the lunar valley is about 160 kilometers long and up to 10 kilometers wide. via NASA https://ift.tt/3jSs9GQ

A very faint but very large squid-like nebula is visible in planet Earth’s sky — but inside a still larger bat. The Giant Squid Nebula cataloged as Ou4, and Sh2-129 also known as the Flying Bat Nebula, are both caught in this cosmic scene toward the royal royal constellation Cepheus. Composed with 55 hours of narrowband image data, the telescopic field of view is 3 degrees or 6 Full Moons across. Discovered in 2011 by French astro-imager Nicolas Outters, the Squid Nebula’s alluring bipolar shape is distinguished here by the telltale blue-green emission from doubly ionized oxygen atoms. Though apparently completely surrounded by the reddish hydrogen emission region Sh2-129, the true distance and nature of the Squid Nebula have been difficult to determine. Still, a more recent investigation suggests Ou4 really does lie within Sh2-129 some 2,300 light-years away. Consistent with that scenario, Ou4 would represent a spectacular outflow driven by HR8119, a triple system of hot, massive stars seen near the center of the nebula. The truly giant Squid Nebula would physically be nearly 50 light-years across. via NASA https://ift.tt/2I4ZTmA

Look to the east just after sunset tonight and you’ll see a most impressive Mars. Tonight, Mars will appear its biggest and brightest of the year, as Earth passes closer to the red planet than it has in over two years — and will be again for another two years. In a week, Mars will be almost as bright — but at opposition, meaning that it will be directly opposite the Sun. Due to the slightly oval shape of the orbits of Mars and Earth, closest approach and opposition occur on slightly different days. The featured image sequence shows how the angular size of Mars has grown during its approach over the past few months. Noticeably orange, Mars is now visible nearly all night long, reflecting more sunlight toward Earth than either Saturn or Jupiter. Even at its closest and largest, though, Mars will still appear over 100 times smaller, in diameter, than a full moon. via NASA https://ift.tt/33yN8cn

What’s happening at the center of spiral galaxy NGC 5643? A swirling disk of stars and gas, NGC 5643’s appearance is dominated by blue spiral arms and brown dust, as shown in the featured image taken by the Hubble Space Telescope. The core of this active galaxy glows brightly in radio waves and X-rays where twin jets have been found. An unusual central glow makes M106 one of the closest examples of the Seyfert class of galaxies, where vast amounts of glowing gas are thought to be falling into a central massive black hole. NGC 5643, is a relatively close 55 million light years away, spans about 100 thousand light years across, and can be seen with a small telescope towards the constellation of the Wolf (Lupus). via NASA https://ift.tt/34nlsWZ

Few astronomical sights excite the imagination like the nearby stellar nursery known as the Orion Nebula. The Nebula’s glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud. Many of the filamentary structures visible in the featured image are actually shock waves – fronts where fast moving material encounters slow moving gas. The Orion Nebula spans about 40 light years and is located about 1500 light years away in the same spiral arm of our Galaxy as the Sun. The Great Nebula in Orion can be found with the unaided eye just below and to the left of the easily identifiable belt of three stars in the popular constellation Orion. The image shows the nebula in three colors specifically emitted by hydrogen, oxygen, and sulfur gas. The whole Orion Nebula cloud complex, which includes the Horsehead Nebula, will slowly disperse over the next 100,000 years. via NASA https://ift.tt/2GB0bRc

How long would it take to drive to the Sun? Brittany age 7, and D.J. age 12, ponder this question over dinner one evening. James also age 7, suggests taking a really fast racing car while Christopher age 4, eagerly agrees. Jerry, a really old guy who is used to estimating driving time on family trips based on distance divided by speed, offers to do the numbers. « Let’s see … the Sun is 93 million miles away. If we drove 93 miles per hour the trip would only take us 1 million hours. » How long is 1 million hours? One year is 365 days times 24 hours per day, or 8,760 hours. One hundred years would be 876,000 hours, but that’s still a little short of the 1 million hour drive time. So the Sun is really quite far away. Christopher is not impressed, but as he grows older he will be. You’ve got to be impressed by something that’s 93 million miles away and still hurts your eyes when you look at it! via NASA https://ift.tt/3jpozUI

As you watched October’s first Full Moon rise last night, the Full Moon closest to the northern autumnal equinox, you were probably asking yourself, « How long would it take to bike to the Moon? » Sure, Apollo 11 astronauts made the trip in 1969, from launch to Moon landing, in about 103 hours or 4.3 days. But the Moon is 400,000 kilometers away. This year, the top bike riders in planet Earth’s well-known Tour de France race covered almost 3,500 kilometers in 21 stages after about 87 hours on the road. That gives an average speed of about 40 kilometers per hour and a lunar cycling travel time of 10,000 hours, a little over 416 days. While this bike rider’s destination isn’t clear, his journey did begin around moonrise on September 27 near Cleeve Hill, Bishops Cleeve, Cheltenham, UK. via NASA https://ift.tt/3kY6n4S