• July 16, 2004 | 10 p.m. ET
A tale of two geysers: In Soda Springs, Idaho, there’s a geyser that’s more faithful than Yellowstone’s Old Faithful. Steamy water erupts every hour, at the top of the hour, and shuts off five minutes later. And it’d be a miracle if it didn’t: Many years ago, the city fathers capped off the geyser with a valve to keep the mineral-laden, stinky spray from discoloring the town’s buildings.
The two geysers rely on similar geological foundations: Water percolates through Earth’s crust and eventually hits a pocket of molten rock that’s closer to the surface than normal. The underground water heats up to incredible pressures, and has to find a way out through the rock above.
In Soda Springs, that way out was created back in 1937 when the city drilled down in search of natural hot water for a swimming pool. The valve was added to keep the spray under control.
At Yellowstone, the mechanism is more natural, and more complex. Hot, mineral-laden water rises in the rocky “plumbing” that leads to Old Faithful’s narrow nozzle, filling up reservoirs and gumming up the pipes with deposits of silica. The constrictions, as well as the weight of the upwelling water, act as a natural valve, reducing the flow and putting the water below under increasing pressure.
Eventually, the pressure becomes so great that superheated steam bursts through the constrictions, blasting the water above through Old Faithful’s nozzle. That blast releases the pressure, setting the stage for another buildup.
Because Old Faithful’s valve is controlled by Mother Nature, the geyser doesn’t work like clockwork: Yellowstone bases its predictions on the size of the preceding eruption, and the times can be off by a few minutes, as they were this afternoon during our visit. But the 3:25 p.m. show was splendid, with sheets of sunlit spray rising 140 feet in the air.
Soda Springs’ eruptions last for five minutes, about the same as Old Faithful’s outbursts. The Idaho blast is a far more intimate affair, however: While more than 500 onlookers crowded around the boardwalk for this afternoon’s eruptions at Old Faithful, my daughter and I were the only ones to catch the beginning of Thursday’s 7 p.m. show in Soda Springs. Shortly after the start, a gaggle of swimsuit-clad youngsters and their parents showed up and joined the party.
You can walk on the silica-laden ground around the Soda Springs opening – something they’d never let you do at Yellowstone. In fact, you can run right through the spray, as the youngsters did. And even if you’re watching from the observation platform, about 30 feet from the geyser, you get a strong whiff of hydrogen sulfide. That’s the classic rotten-eggs smell that accompanies most geysers, including Old Faithful if the wind is blowing in the right direction. Or should that be the wrong direction?
This weekend, we’ll finish looking around Yellowstone and head back to our home base in the Seattle area. Unless we’re unavoidably detained, your regular Cosmic Log service should resume Monday.
• July 15, 2004 | 11:30 a.m. ET
Greetings from Martian America: The forested mountains of northeastern Utah can be as green and inviting as any in the world, but just over the ridge, you can find an alien landscape as well: rolling hills of red dirt and rock, much like the vistas visible from the Spirit rover on Mars.
The similarity isn't just coincidental. Like at least part of the Red Planet, Utah's red hills were once covered with water. In fact, as you drive through Logan Canyon, the fossilized traces of marine worms from 400 million years ago are visible literally on the side of the road. Today, that bounty of water is gone, leaving Martian-style dirt and stone that is reddened by iron oxide.
To the south, Utah's desert terrain has served as a scientific stand-in for Mars, and there are even parallels between the intriguing pellets known as Martian blueberries and Utah's mysterious "moqui marbles."
For all those parallels, there's one big difference, of course: Even among northeastern Utah's red rocks, greenery can be found.
In fact, as you look across the hills, you might not realize you're looking at a red planet until you get up close.
But for someone who generally sees more pictures from Mars than from Logan Canyon, the visit is an eye-opener.
If the "greening of Mars" someday actually becomes possible, one could imagine that a Utah-style biosphere would be an early model.
This summer, the frontier of Mars on Earth is in a different locale: Devon Island in the Canadian Arctic. Keep up with the dispatches from the Haughton Mars Project and the Flashline Mars Arctic Research Station. And stay tuned for more about the honest-to-goodness Mars on Friday, when NASA provides its latest update on the Mars rover missions. You can watch Friday's 1 p.m. ET news briefing via Go to MSN Video to watch Live Coverage of the Mars missions.
Meanwhile, our road trip continues: We'll be getting ready for a hot date with Old Faithful at Yellowstone National Park.
• July 14, 2004 | 11:45 a.m. ET
Roadside illusions: When you're in the midst of a 2,000-mile drive through the American West, your eyes can sometimes play tricks on you — and not just because you've been driving for eight hours. That seemingly slick highway may turn out to be totally dry, and those mountains that loom so large and close could be much farther away than you think.
Today we're in Laramie, Wyo., musing on some of the scientific mysteries raised during our dash across the wide, flat state of Nebraska:
Raindrops? Would you believe 'rainblobs'? It looked as if the rain was coming down in sheets when thunderstorms swept over Nebraska on Monday night. But do raindrops really come down as sheets, needles or tapered teardrops? Not really. Ironically, a raindrop frozen in time would look more like a tiny umbrella (or parachute, or jellyfish).
In the online version of the Geophysical Research Letters, University of Washington researchers report the discovery of monster drops that measure as much as a centimeter (almost a half-inch) wide. But these were exotic specimens, found by combing data about rainfall in Brazil and the Marshall Islands. Raindrops usually break up into smaller bits when they get 5 millimeters (two-tenths of an inch) wide.
So why do we think of drops as having a stretched-out or classic "teardrop" shape? That has to do with the way our eyes and brain process visual information about water droplets as they dribble from a faucet, or fall through the glare of a streetlight. For more about the teardrop illusion, check out the "Bad Science" Web site and PBS' "Scientific American Frontiers."
Highway mirages: As my teen-age daughter looked down Interstate 80 on a 90-degree day, with nary a cloud in the sky, she noticed that the road ahead seemed to be covered with a sheen of water ... or was that wet asphalt? Of course, it was neither. Instead, the shimmering reflection is actually caused by refraction. As light rays passed through a hot layer of air close to the highway surface, they were bent — making it look as if the highway is reflecting the glint of the sky or even the image of the car ahead of us.
The phenomenon is a variation of the classic desert mirage. To learn much more about such mirages, pay a visit to the Weather Doctor.
Purple mountains' majesty: Another type of mirage can affect the way we see mountains, refracting light to make them appear larger. And that plays off our perception that bigger objects are closer than smaller objects. Once again, consult the Weather Doctor for an explanation of this "towering" phenomenon.
There's another type of mountain illusion, also having to do with atmospheric refraction. Water vapor in the air tends to scatter wavelengths toward the red side of the spectrum, which explains why the sky is blue . The light reflected from more distant objects has to travel through more of the haze — hence, they tend to appear bluer. As noted in this Encarta encyclopedia article, the scattering phenomenon is what makes mountains purple in the song "America the Beautiful."
If the atmosphere is particularly clear and dry, the light-scattering is reduced. As a result, distant objects are less blue, and we perceive them as closer.
As we look west from Laramie, the mountains ahead are looking pretty purple — so it's time to hit the road. We're hoping to be in Utah tonight.
• July 13, 2004 | 8:26 pm ET
On the road, wirelessly: A quarter-century ago, motels across the country used to splash three little words on their signs to bring in road-weary travelers: “HBO Color TV.”
Today, three different words light up the readerboards: “Free Wireless Internet.”
Welcome to the real-life information superhighway: This week I’m in the midst of a cross-country trip from eastern Iowa to western Washington, and today’s dispatch comes from the Heartland Inn in Council Bluffs, Iowa.
You know that wireless has arrived when it’s offered at campgrounds and even at the roadway rest stop on Interstate 80 near Casey, Iowa. The biggest problem in the search for roadside wireless is knowing exactly what you’re getting: A good number of inns are advertising “high-speed Internet” even though it’s nothing more than a dataport on the side of the hotel-room phone.
Fortunately, Wi-Fi guides such as PluggedInns are popping up to address the need for speed. (Unfortunately, not all of PluggedInn’s search features are ready for prime time yet.) And if you strike out in the hotel search, you can look around for other Wi-Fi hotspots using more general guides such as WiFi 411.
It’s only a matter of time before broadband travel guides go mainstream, right down to the little logos in the AAA guidebooks. And the trend isn’t limited to the United States, as this article from the New Zealand Herald illustrates. For more about the wireless hotel trend, check out Forbes’ Top 10 guide .
Now that I’ve been able to check my e-mail, I can pass along some items from the mailbox that caught my fancy:
- Zero Gravity Corp. is taking reservations for airplane flights that offer waves of weightlessness, starting in October (via Clark Lindsey’s Space Log).
- Rocket Boosters is shipping out SpaceShipOne paraphernalia, including the long-looked-for, hand-canceled postcards from flight day.
- The Cassini spacecraft has emerged from behind the sun and is ready to send back more pictures from Saturn and its surroundings.
- Newly available software lets you process your own imagery from the Hubble Space Telescope and other observatories.
- Researchers hook up humans to play video games using only their brains.
- “Virtual clay” lets you make sculptures in cyberspace.
Now it’s time to hit the road. Next stop: Wyoming.
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