• Water Flowed on Mars


    Welcome to Intricate Osuga Valles

    The search for water on Mars keeps turning up evidence that something wet once flowed across its surface. Images like this one from the Mars Express orbiter show streamlined islands and narrow gorges that were carved out by fast-moving water sometime in the distant past. This one shows a region near the Vallis Marineris canyon complex that splits the mid-section of the planet. Captured on December 7th, 2013 by the Mars Express cameras, this view is of the Osuga Valles region. It’s an outflow channel that emanates from a region of what planetary scientists call chaotic terrain (that is, chaotic landscapes disrupted in some way).

    Flow features on Mars
    A perspective view of Osuga Valles on Mars, showing braided river valleys that once carried water across the surface. Courtesy ESA/Mars Express.

    The search for water on Mars keeps turning up evidence that water once flowed across its surface. Images like this one from the Mars Express orbiter show streamlined islands and narrow gorges that were carved out by fast-moving water sometime in the distant past. This one shows a region near the Vallis Marineris canyon complex that splits the mid-section of the planet. Captured on December 7th, 2013 by the Mars Express cameras, this view is of the Osuga Valles region. It’s an outflow channel that emanates from a region of what planetary scientists call chaotic terrain (that is, chaotic landscapes disrupted in some way).

    So, what caused this scene? The most likely explanation is an episode of chaotic flooding (extremely heavy flash flooding) that sent water and rocks and mud rushing across the landscape and carving out these channels and gullies. The geologic evidence here suggests that there were likely several bouts of flooding, creating these grooved valley floors and islands.

    Continue reading  Post ID 6631



  • Red Moon Risin’


    Will You See It?

    By now everybody knows there’s a lunar eclipse happening next Monday night into Tuesday.  Those of us who live in North America, most of South America, parts of the Pacific and Asia will see all or some of the eclipse. For folks in England and parts of western Europe it will be only a short-lived penumbral eclipse, meaning that they’ll see the Moon in the lighter parts of Earth’s shadow for a short time. The same thing is true for people in eastern Asia and Oceania. A huge swath of the South Pacific and Antarctica get to see the full eclipse, so if you’re watching from the VERY far South, dress warmly!

    Here’s a graphic from the folks at Time and Date that gives you a pretty good idea of who will see what parts of the eclipse. Check out their eclipse page for a lot of really good information and clickable links to show you when the eclipse will occur over various parts of the globe. Also check out MrEclipse.com for further information, Eclipsemaps.com for good charts, and NASA’s Eclipse page, which has a lot of cool technical information if you really want to geek out on eclipses.

    What will you during the lunar eclipse? The deepest red indicates places where observers can see the entire eclipse. The red shading on either side of the darkest red covers observers who will see the eclipse until the Moon sets/Sun rises. Beyond that are the folks who will see the eclipse after the moonrise/sunset. If there’s no coloring over your area of the world, then you don’t see any part of the eclipse. Courtesy Timeanddate.com.


  • There’s a Red Moon on the Rise


    Get Ready for the April 14-15 Total Lunar Eclipse

    On Monday April 14th, late in the evening for most folks in the U.S., the Moon will pass through Earth’s shadow. That event, called a total lunar eclipse, will begin just before 4:55 a.m. UTC on April 15th, (that’s 12:55 a.m., EDT, 11:55 p.m. CDT, 10:55 p.m. MDT, and 9:55 p.m. PDT on April 14th) and last for several hours before it passes out of the shadow. Sure, it’s early in the morning for most of us, but you don’t get to see these things very often, so I advise you make some plans to stay up late (maybe after you’ve made that last mad dash to the Post Office to mail your taxes (if you’re in the U.S.) and watch the show. To help you along, the folks at the Slooh.com will be hosting a five-hour event, starting with coverage of Mars, starting at 7 p.m. PDT. They’ll focus their telescopes on the Red Planet, and then the eclipse. Along the way, you’ll hear from astronomy experts, giving their view on the events occurring the sky.

    A Stellarium view of the April 14-15 total lunar eclipse. (Stellarium.com)
    A Stellarium view of the April 14-15 total lunar eclipse during the darkest part when the Moon is in the umbral part of Earth’s shadow. (Stellarium.com)

    If you do take the opportunity to see the eclipse, here’s what you can expect. First, as the Moon slips into the penumbra (the outer shadow), it will start to get slightly dark. In all fairness, it will be fairly difficult to tell the Moon is darkening during this phase, unless you have a light meter and can measure the changing albedo of the Moon. However, once it slips into the umbra (the full Earth shadow) at 12:08 a.m. PDT (3:08 a.m. EDT), the Moon will be noticeably darker, and begin to take on a coppery-red color. It appears not too far from the bright shiny star Spica, with Red Mars not too far away, and brilliant Saturn at lower left.

    Eventually the Moon leaves the umbra at 1:23 a.m. PDT (5:23 a.m. EDT), moving back into the penumbra, and the eclipse ends at 3:36 a.m. PDT (6:36 a.m. EDT).

    People all over the Americas will be able to see this eclipse, along with folks in parts of the Pacific (see a complete list here) will be able to glimpse some or all of it.

    I’ve witnessed I don’t know how many lunar eclipses and have seen four total solar eclipses and one annular. Each one is special, and different. Each one brings with it a sense of awe, and teaches us just how cool it is that our Earth orbits the Sun, our Moon orbits Earth, and sometimes they all line up in just the right way in a perfectly normal occurrence that happens over and over again.

    Give yourself the gift of a lunar eclipse next week. Start planning now to watch as Earth’s shadow slips across the face of the Moon. For more information on the eclipse, visit MrEclipse.comand Timeanddate.com. And, if the weather’s poor at your location, or you’re in an area where the eclipse can’t be seen at all, be sure and check out the Slooh.com webcast.