Monicks: Unleashed

Tag: astronomy

  • How will Jupiter hold up his pants? Jupiter is nekkid!

    via blogs.discovermagazine.com

    From Emily at The Planetary Society blog comes word that one of Jupiter’s belts has disappeared… again.

    This image, by the accomplished amateur astronomer Anthony Wesley, shows what’s up. Usually, the Great Red Spot is accompanied by a dark reddish belt that goes all the way around the planet, like the one in the northern hemisphere you can see in the picture. However, the Southern Equatorial Belt, as it’s called, is gone!

    This has happened before, in fact. It’s not clear exactly why this sort of thing occurs, though. The belts (and their lighter-colored cousins, called zones) are weather patterns that stretch around the planet, a bit like the jet stream on Earth. They can be affected by temperature, chemical composition, and other factors. It’s possible that a belt can sink lower in the Jovian atmosphere if it cools slightly. Clouds then pour in on top of it, hiding it from view. It’s still there, just hidden; if the temperature rises it can float back up like nothing ever happened.

    Jupiter is a weird place. Remember, we only see the very tops of the clouds. They go all the way down, tens of thousands of kilometers deep, where the pressure gets so great the gas just sorta gradually turns into a liquid. So having a belt sink a little bit and disappearing is perhaps less unlikely with such a freaky planet than it would be on Earth.

    But there is a very cool thing about this: you can see it for yourself! It only takes a small telescope to see Jupiter, and with a modest ’scope the belts are visible. Well, usually visible; not this one so much right now, but you get my drift. If you want to see this for your very own self, you’ll have to get up early: Jupiter doesn’t rise until very early morning. Get up an hour or so before dawn and you should be able to get a good look. It’ll be the very bright starlike object in the East, brighter than anything else in the sky except the Moon, so it’s easy to spot.

    But if you prefer your astronomy to be virtual, you can check out other pictures at Wesley’s site, as well as Astro Bob’s blog.

    I wonder how long the belt will be gone? It could be months, or it might pop back up sooner. Either way, it’s a good reminder that we still have a lot of stuff to figure out when it comes to the Universe around us.

    Posted via web from Monicks: Unleashed

  • The Earth and Moon from Mars | This is so beautiful!

    via i.dailymail.co.uk

    Stunning image of what our planet looks like from the Red Planet.

    This stunning picture is the first image of Earth ever taken from another planet that shows our home as a planetary disc, with the Moon in the distance

    Captured by Nasa’s Mars Reconnaissance Orbiter as the spacecraft orbited the Red Planet, both the Earth and the Moon appear as crescents, engulfed in the vast darkness of space.

    Our planet is captured in a ‘half-Earth’ phase, while the image also shows the Earth-facing hemisphere of the Moon.
    Because the Earth and the Moon are closer to the Sun than Mars, they exhibit phases, just as the Moon, Venus, and Mercury do when viewed from Earth.
    When the image was captured in 2007, Earth was 88million miles from Mars, giving the HiRISE image a scale of 88 miles per pixel.
    Nasa could only picture the Earth and moon at full disk illumination when they are on the opposite side of the Sun from Mars. However, then the range would be much greater and the image would show less detail.
    On the Earth image you can make out the west coast outline of South America at lower right, although the clouds are the dominant features.
    This image required a processing, with the Moon image brightened so it would show up next to Earth.

    Posted via web from Monicks: Unleashed

  • Picture of the Day – Herschel Finds a Hole in Space

    via spacefellowship.com

    NGC 1999 is the green tinged cloud towards the top of the image. The dark spot to the right was thought to be a cloud of dense dust and gas until Herschel looked at it. It is in fact a hole that has been blown in the side of NGC 1999 by the jets and winds of gas from the young stellar objects in this region of space. Credits: ESA/HOPS Consortium

    ESA’s Herschel infrared space telescope has made an unexpected discovery: a hole in space. The hole has provided astronomers with a surprising glimpse into the end of the star-forming process.

    Stars are born in dense clouds of dust and gas that can now be studied in unprecedented detail with Herschel. Although jets and winds of gas have been seen coming from young stars in the past, it has always been a mystery exactly how a star uses these to blow away its surroundings and emerge from its birth cloud. Now, for the first time, Herschel may be seeing an unexpected step in this process.

    A cloud of bright reflective gas known to astronomers as NGC 1999 sits next to a black patch of sky. For most of the 20th century, such black patches have been known to be dense clouds of dust and gas that block light from passing through.

    When Herschel looked in its direction to study nearby young stars, the cloud continued to look black. But wait! That should not be the case. Herschel’s infrared eyes are designed to see into such clouds. Either the cloud was immensely dense or something was wrong.

    Investigating further using ground-based telescopes, astronomers found the same story however they looked: this patch looks black not because it is a dense pocket of gas but because it is truly empty. Something has blown a hole right through the cloud. “No-one has ever seen a hole like this,” says Tom Megeath, of the University of Toledo, USA. “It’s as surprising as knowing you have worms tunneling under your lawn, but finding one morning that they have created a huge, yawning pit.”

    The astronomers think that the hole must have been opened when the narrow jets of gas from some of the young stars in the region punctured the sheet of dust and gas that forms NGC 1999. The powerful radiation from a nearby mature star may also have helped to clear the hole. Whatever the precise chain of events, it could be an important glimpse into the way newborn stars disperse their birth clouds.

    Posted via web from Monicks: Unleashed