Saturn’s mysterious hexagon has changed from blue to gold – and no one knows why – ScienceAlert

It’s like nothing we’ve seen on any other planet in the entire Universe, and now the mysterious structure on Saturn’s north pole just got even weirder.In just four years, Saturn’s hexagon has changed its colour from blue to gold. So far, our best guess as to why this change occurred is that this is what it looks like when Saturn’s north pole gears up for next year’s summer solstice.

Source: Saturn’s mysterious hexagon has changed from blue to gold – and no one knows why – ScienceAlert

Astronomers Map Millky Way in Incredible Detail – Sky & Telescope

Astronomers have mapped atomic neutral hydrogen across the entire sky, creating an unprecedented portrait of our galaxy and some of its nearest neighbors.HI4PI maps Milky Way’s neutral hydrogenThis map depicts the radiation from neutral atomic hydrogen (HI) across the entire sky, as seen by the Parkes and Effelsberg radio telescopes. Our galaxy, the Milky Way, appears as a luminous band across the sky with the Galactic Center in the middle. The Large and Small Magellanic Clouds are prominently visible in orange below the Galactic plane. They are surrounded by huge clouds of gas, forcefully disrupted from their hosts by gravitational interaction with the Milky Way. The HI emissions of the Andromeda galaxy (M31) and its neighbor, Triangulum (M33), are also easy to spot as bright purple ellipses in the lower left. The gas motion is color-coded to represent the gas’s motion, and the visual brightness in the image relates to how much neutral hydrogen is present. Click for bigger image.HI4PI CollaborationHydrogen is the single most abundant element in the universe. The simple pairing of a proton and electron is so reactive that atomic hydrogen doesn’t occur naturally on Earth — it reacts with itself or other elements to form molecules instead. But in the large, mostly empty space between stars floats a copious amount of neutral atomic hydrogen.We only know it’s there when the atom’s lone electron very occasionally flips from an “up” state to a “down” state, releasing a single 21-centimeter radio wave. Modern radio telescopes can easily pick up the faint signal, which multiplies thanks to the wealth of hydrogen atoms. What’s hard is to map that signal across the entire sky — and that’s exactly what astronomers have done in unprecedented detail.Using two of the world’s largest fully steerable radio dishes, the 100-meter Effelsberg dish near Bonn, Germany, and the 64-meter Parkes dish west of Sydney, Australia, astronomers have generated a survey they’ve dubbed HI4PI. Pronounced “hi four pie,” the survey refers to the abbreviation for neutral hydrogen (HI) and the geometrical reference to the whole sky (4PI, or 4π).Over thousands of hours on the sky, the dishes took more than a million individual observations. Thousands more hours went into processing dozens of terabytes of data, removing radio interference from broadcast stations, military radar, and other Earthbound sources, then stitching everything together into a seamless map of the hydrogen sky.The resulting image is incredible: the ultrafine detail reveals fine threads and diffuse clouds in the interstellar medium never seen before. And for astronomers studying faraway X-ray or gamma-ray sources, the map will prove essential in cleaning the window to the distant universe.The map shows not only the amount of hydrogen at each celestial location, but also the motion of hydrogen across the sky: the 21-centimeter radio signal shifts to slightly lower or higher energies as the hydrogen gas moves toward or away from us, respectively. Watch the video below to take a stepwise look through the data, seeing first the most negative velocities (infalling gas, moving toward Earth) and ending with the most positive radial velocities (receding gas from Earth’s perspective).HI4PI data is available to scientists through the Strasbourg astronomical Data Center.CATEGORIESGalaxies, Milky Way, NewsTAGSMilky Way GalaxyRELATED POSTSWhat percentage of our galaxy’s stars move in retrograde orbits?Monica Young About Monica YoungMonica Young, a professional astronomer by training, is web editor of Sky & Telescope, where she creates, manages, and maintains website content, and contributes to the magazine.View all posts by Monica Young → 2 thoughts on “Astronomers Map Milky Way in Incredible Detail” Robert-Casey Robert-Casey October 26, 2016 at 3:21 pm Looks like you can see the Sun’s motion around the galaxy along with the hydrogen clouds. Just to the right of center, looks like the clouds are moving towards us, and to left of center receding away. Extreme left, the clouds are moving towards us, and extreme right, receding away. What you’d see in a system where objects closer to the galaxy’s center would orbit faster, and objects further away than we are orbit slower. Though the dark matter halo around the galaxy would make this effect lower amplitude. Looks like the Sun and us is heading to a point halfway to the left. Log in to Reply ↓ Anthony Barreiro Anthony Barreiro October 26, 2016 at 7:46 pm In this equal-area map of the sky, the parts of the Milky Way to the left of galactic center are closer to us than the parts to the right of galactic center. (Remember that we would stitch the edges of this projection to one another to recreate the celestial sphere, so the parts of the galactic central plane that are farthest to the left and farthest to the right are actually right next to one another.) It seems to me that the parts of the galaxy

Source: Astronomers Map Millky Way in Incredible Detail – Sky & Telescope

Britons now carry less than £5 in cash in their wallets, Mastercard reveals – Retail Times

Bulging with 44 items – the anatomy of the typical British wallet/purse: 2 x debit/credit cards Less than £5 in cash 1 x driving licence 2 x membership cards 2 x entry/pass cards 2 x travel cards/tickets 4 x loyalty cards 3 x money off coupons 3 x business cards 2 x photographs 2 x keepsakes/lucky charms 4 x old receipts 2 x expired coupons 2 x useless handwritten notes 3 x expired or unused membership/certification/identity cards 6 x pieces of unneeded foreign currency 2 x business cards of people never contacted 2 x expired travel tickets

Source: Britons now carry less than £5 in cash in their wallets, Mastercard reveals – Retail Times

Scientists uncover evidence of impending tipping point for Earth | Berkeley News

A prestigious group of scientists from around the world is warning that population growth, widespread destruction of natural ecosystems, and climate change may be driving Earth toward an irreversible change in the biosphere, a planet-wide tipping point that would have destructive consequences absent adequate preparation and mitigation.

Source: Scientists uncover evidence of impending tipping point for Earth | Berkeley News

BBC Food – Rise of the ‘semi-vegetarians’

Sales of meat alternatives are increasing. But who is eating protein substitutes and why?”I find that I used to adore meat, but now a meat substitute burger does it for me, when I have it with onions and ketchup, it does the job. I guess it reminds me of the taste,” David Finney admits.He turned his back on meat seven years ago, and uses meat alternatives for variety in his meals.

Source: BBC Food – Rise of the ‘semi-vegetarians’