DaveMurray's Blog

NOAA Maritime Archaeologists Discover Shipwreck of British Whaling Ship Gledstanes that Sank off Kure Atoll in 1837  

NOAA archaeologist measures the bore to a small cannon on the Gledstanes.

High resolution (Credit: NOAA)

A team of maritime heritage archaeologists from NOAA’s National Marine Sanctuaries have discovered the shipwreck remains of the 1837 British whaling ship Gledstanes. The shipwreck was foundoff Kure Atoll within the Papahanaumokuakea Marine National Monument during a month-long expedition to discover and document shipwrecks in monument waters.

At the end of the first exploratory dive of the day, the NOAA dive team discovered a pile of iron ballast and some chain. The ballast led to a trail into the dramatic topography of the reef where more artifacts were found scattered, including four massive anchors, iron ballast, cannons and cannon balls, a trypot.

“For years I have been coming up to Kure Atoll in hopes of searching for this particular shipwreck, but in the past we have been deterred by the weather and unworkable conditions,” said Kelly Gleason, NOAA archaeologist for the Monument and mission leader. “This year, the Gledstanes was revealed to us, and we couldn’t be more thrilled with the opportunity to share this wreck site and its story with the public.”

"The story of the Gledstanes and her survivors is limited, but adds to the important legacy of shipwreck survival stories at Kure Atoll,” said Hans VanTilburg, maritime heritage coordinator for NOAA's National Marine Sanctuaries' Pacific Islands Region. After the loss of their ship due to extremely rough seas, the crew launched the ship’s small boats and made for the closest dry land — the small sandy island at Kure Atoll named Ocean Island. In a short time, the Gledstanes broke apart in the heavy surf. The crew salvaged what they could from their destroyed ship and set about fashioning a 38-foot vessel called the Deliverance.

One of the four large anchors found at the wreck of the Gledstanes.

High resolution (Credit: NOAA)

The Gledstanes is the fourth whaling ship, and one of the oldest ships, discovered thus far in the Papahanaumokuakea Marine National Monument, shedding further light on the major significance of 19th-century whaling heritage in this region.

The researchers aboard the NOAA ship Hi‘ialakai will also make stops at French Frigate Shoals, Pearl and Hermes Atoll and Midway Atoll. The public can follow this month-long mission on the monument’s Web site.

Papahanaumokuakea Marine National Monument is administered jointly by three co-trustees — the Department of Commerce, Department of the Interior and the State of Hawai‘i — and represents a cooperative conservation approach to protecting the entire ecosystem. Co-trustee agencies in cooperation with the Office of Hawaiian Affairs manage the monument through the Monument Management Board. The Monument area includes the Northwestern Hawaiian Islands Coral Reef Ecosystem Reserve, Midway Atoll National Wildlife Refuge/Battle of Midway National Memorial, Hawaiian Islands National Wildlife Refuge, Kure Atoll Wildlife Sanctuary, and Northwestern Hawaiian Islands State Marine Refuge.

 

*** THE FALL FORECAST IS ONLINE.  NO T.V. SPECIAL IN THE FALL...JUST ONLINE. SEPTEMBER...OCTOBER AND NOVEMBER OF 2008...THE WINTER FORECAST WILL BE OUT IN MID NOVEMBER:

CLICK HERE TO READ THE FALL 2008 FORECAST

VERY WEIRD WEATHER TIMES ON THE MAPS...THE JET IS WAY NORTH--WHERE IT SHOULD BE...AND WE CONTINUE TO DEAL WITH THE TWO CUT OFF LOW PRESSURE SYSTEMS...THE SOUTHERN PLAINS LOW AND "FAY"...THE BIG LOW HAS A HUGE POOL OF COOL AIR DRIFTING WITH IN--SOME AMAZING TEMPS UNDER THAT LOW PRESSURE AND DEALING WITH WHATS GOING ON WITH "FAY" THIS SHOULD POP BACK INTO THE ATLANTIC FIRST THING WEDNESDAY MORNING--WATCH IT RAMP UP...BECAUSE THERE IS NO MAJOR PUSHING POWER--IDEAS ARE ALL OVER THE PLACE ON WHAT FAY WILL DO...CAN'T BUY INTO A LOT OF THE MODEL MESS...LETS BRING IT NORTH WITH ANOTHER LANDFALL BETWEEN JACKSONVILLE AND CENTRAL GEORGIA...BUT THIS MOISTURE POCKET SHOULD HANG AROUND FOR SEVERAL DAYS. IT WILL PREVENT THE PLAINS LOW PRESSURE FROM MOVING MUCH--SO WE GO MORE UNSETTLED--SHOWERS AND SOME STORMS LATE WEDNESDAY NIGHT AND INTO THURSDAY...AFTER THAT--WE NEED TO GET A BETTER IDEA OF WHAT FAY WILL DO...AND HOW MUCH THE ATMSOPHERE WILL GET MOVING--SO LOTS OF QUESTIONS ABOUT THE WEEKEND

 

STAR CHART INFO:

 

 

Mercury and Venus appear closest on the 20th. Mars, meanwhile, is gradually moving toward them from the upper left day by day, and Saturn is fast disappearing to their lower right. Sky & Telescope diagram

 

 

 

In early and mid-July, when Comet Boattini is up before dawn in a moonless sky, it will be between the rump of Taurus and the head of Cetus. Your eastern horizon will cross this part of the sky at an angle that depends on your latitude, and a height that depends on the time you look. The best time will probably be about 5 to 15 minutes after the start of morning twilight; use our online almanac to find this time as described at left. Sky & Telescope diagram

THE COOL PIC OF THE DAY:

FOR THE WEATHER HISTORY ON THIS DATE...HEAD TO THIS SITE:

http://www.weatherforyou.com/history/

As always...enjoy the weather...Dave

"the best forecasters are not always certain where they are in the atmsophere...but they are always aware of their uncertainty"

Don't forget when your in your car you can get my forecast on:

KHITS 96

105.7 THE POINT

KSHE 95

Ocean “Dead Zones” Increasing: 400 Oxygen-Deprived Areas Now Exist by Matthew McDermott, Brooklyn, NY on 08.15.08

image: NASA

Every year the topic of the dead zone in the Gulf of Mexico seems to pop up on TreeHugger—most recently in a report which links expanded corn production to the increasing size of the zone. New research shows that it’s not just in the Gulf that ocean dead zones are expanding but throughout the world.

Dead Zones Have Doubled Every 10 Years Since 1960s
According to the study, the number of marine dead zones—areas which are periodically or permanently starved of oxygen—has doubled every 10 years since the 1960s, with those along coastlines increasing in size and intensity. Currently there are about 400 coastal areas, with a combined area larger than the size of Oregon, with such poor water quality, with so little oxygen that only microbes can survive in it. Fish and crustaceans must flee the area or die.

Map showing partial number of current marine dead zones: Dr Robert Diaz/NASA

Fertilizer Run-Off, Sewage Worsen the Problem
The reason for the increase? The predictable culprit of human activity.

The New York Times describes what is happening:

Nitrogen from agricultural runoff and sewage stimulates the growth of photosynthetic plankton on the surface of coastal waters. As the organisms decay and sink to the bottom, they are decomposed by microbes that consume large amounts of dissolved oxygen. Most animals that live at the bottom of the coastal ocean cannot survive as oxygen levels drop.

 

image: US DEP

Stop the Runoff and the Dead Zones Could Recover
And steps that can be done the address the problem:

Robert W. Howarth, a professor of ecology and environmental biology at Cornell, said that methods to reduce nitrogen-rich runoff exist, including planting winter rye or winter wheat in cornfields during the off-season so the spring rains do not cause the chemicals to leach into waterways. [TH note: You could also decrease the amount of fertilizer used...]

 

Nevertheless, most experts agree that the changes needed to reverse the trend are dramatic. For example, scientists estimate that cutting the Gulf of Mexico’s dead zone by a third would require a 45 percent decrease in nitrogen-rich runoff from the Mississippi River watershed, which extends into the croplands of the upper midwest.

 

Want to know more? NASA has a pretty good overview of the issue of marine dead zones.

via :: The New York Times

The Realm of Earthworms: NASA Gets Down to the Nitty-Gritty

08.15.2008

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August 15, 2008: When you hear the word "NASA," do visions of rocket ships dance in your head?

Well think again. From now on, it's "earthworms."

That's right. Using space technology, NASA is now studying the realm of earthworms, millipedes, and springtails -- the soil beneath your feet -- with a project called OMEGA (Observing Microwave Emissions for Geophysical Applications).

Right: A subterranean cross-section of Alabama soil. Credit: USDA. [more]

Why would an agency whose cosmic vision knows no bounds care about the nitty-gritty crawling-grounds of lowly critters? Because NASA recognizes the vital role this "underworld" plays in our lives on Earth. For instance, if forecasters don't know how damp or dry the soil is, they can't accurately predict the weather.

"OMEGA soil moisture data will help us build better weather models," says NASA scientist Chip Laymon, principal investigator for the OMEGA project at the National Space Science and Technology Center in Huntsville, Alabama. "Better models mean better forecasts."

Sign up for EXPRESS SCIENCE NEWS delivery But there's more. According to Laymon, this research could help forecasters predict flash floods, land-slides and drought. OMEGA could also help farmers plan crop planting, make important decisions about irrigation, and predict crop yields.

How will OMEGA scientists gather the soil moisture data? "We use a microwave radiometer," says Laymon. Ordinary soil naturally emits a small amount of low-energy microwave radiation; all warm objects do. "By analyzing those microwaves we can tell how much moisture is in the soil."

The name of the instrument is MAPIR, short for Marshall Airborne Polarimetric Imaging Radiometer, and it's about to fly on its first mission onboard a NASA P-3 aircraft. "Our instrument has to be ready to install on the P-3 by Sept. 15," says Laymon. "We'll then fly missions over the Delmarva Peninsula between Oct. 1 and Oct. 14."

The Delmarva Peninsula, a 180 mile x 60 mile area of land on the east coast of the United States bounded by the Chesapeake Bay and the Atlantic Ocean, is a good place for MAPIR's maiden flight. Two-thirds of the peninsula is agricultural and one-third forested, so there is a variety of terrain to sample. Moreover, the USDA Agricultural Research Service has already been studying the area and they have set up their own moisture sampling stations. These can provide valuable "ground truth" comparisons for MAPIR's airborne data.

Above: OMEGA's microwave soil moisture sensor, MAPIR, will take its maiden flight onboard a NASA P-3 aircraft like this one. Photo credit: Stephen Ausmus, USDA-ARS

MAPIR's berth on the P-3 was an unexpected development. "Another mission slated to fly on the P-3 scrubbed, and a slot suddenly opened for us," says Laymon. "We've really had to accelerate our schedule for developing MAPIR. The intensity of the schedule is enormous -- trying to refocus and prepare for airworthiness reviews and other milestones. The team has worked tirelessly and we have many more long days to come."

The ultimate goal is three tiers of observation: OMEGA instruments on a truck and a plane, and a similar instrument built by NASA's Jet Propulsion Laboratory, on a satellite. Each sensor will tell the story of soil moisture from its own unique perspective. The truck, with its own huge microwave antenna, is almost ready. The satellite will most likely be in the form of the 2013 Soil Moisture Active Passive, or SMAP, space mission led by JPL. After the P-3 test-flight, OMEGA's regular plane will be a Polish-built Antonov aircraft, a big beefy biplane housed at a local airfield, affectionately known to the team members as "the flying tractor."

Right: The "Flying Tractor" awaits MAPIR in an Alabama air field.

"With this aircraft, we'll be able to do a lot of research locally. I expect 'the flying tractor' to be airborne before the end of the year," says Laymon.

Meanwhile, the rush to prepare for the upcoming P-3 flights has strained OMEGA researchers to the max. What's the hardest part? "Oh, probably the hallucinations from stress and lack of sleep," grins Laymon. No matter how hard he tries, he can't stop thinking about flying tractors and a universe of earthworms.

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Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA

A Flash of Insight: LCROSS Mission Update

08.11.2008

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There are places on the Moon where the sun hasn't shined for millions of years. Dark polar craters too deep for sunlight to penetrate are luna incognita, the realm of the unknown, and in their inky depths, researchers believe, may lie a treasure of great value.

NASA is about to light one up.

Sometime between May and August 2009, depending on launch dates, the booster stage for NASA's LCROSS probe will deliberately crash into a permanently-shadowed lunar crater at 9,000 km/hr, producing an explosion equivalent to about 2,000 pounds of TNT (6.5 billion joules). The blast will jettison material out of the crater into broad daylight where astronomers can search the debris for signs of lunar water.

Water is the treasure. NASA plans to send people back to the Moon by 2020 and eventually set up a lunar outpost. Water would be an invaluable resource for astronauts living and working on the Moon. Not only could people drink it, but water could be used to grow plants for food, or it could be split into hydrogen for rocket fuel and oxygen to replenish the outpost's air. It even could shield astronauts from dangerous space radiation.

Hence the kamikaze mission, called the Lunar CRater Observation and Sensing Satellite (LCROSS), to search for H₂O on the Moon. "If LCROSS's booster stage hits a patch of lunar regolith that contains at least 0.5 percent water ice, water should be detectable in the plume of ejecta," explains Anthony Colaprete, principal investigator for LCROSS at NASA's Ames Research Center.

Right: The LCROSS booster stage hurtles toward the Moon as the mission's robotic satellite looks on. [more]

The other half of the LCROSS mission, a robotic satellite, will observe the impact and then itself crash into the Moon 4 minutes later. Most of the Moon is bone dry, of course. With virtually no atmosphere and 300° temperature swings between night and day, most of the Moon's surface is a hostile place for water. But there are a few cold, dark places where frozen water could stay put. At the lunar poles, the sun is always low on the horizon, so some crater ridges cast shadows that keep parts of the crater floors in perpetual darkness. Temperatures in the inky black shadows hover around 40° above absolute zero (-233° Celsius), cold enough for water ice to survive indefinitely.

"There's tantalizing evidence that water might be there," Colaprete says. A lunar orbiter called Clementine detected hints of water ice in some of these craters in 1994 and so did the 1999 Lunar Prospector mission, but unfortunately the data were not conclusive.

That's where LCROSS comes in. Ice blasted into the sunlight by the impact would vaporize. Ultraviolet light from the sun would then split the H₂O molecules into H and OH. Mission planners hope LCROSS's sensors will detect the fingerprint of H₂0 in near-infrared light and also a characteristic wavelength emitted by OH at 308 nanometers.

Above: The "life cycle" of LCROSS's impact plume. Click on the image to view a larger diagram and more information.

Currently, Colaprete's team is searching for the best impact sites inside various shadowed craters. "The first and most important criterion is that we think the impact area will be productive from an ejecta standpoint," Colaprete explains. "If we don't get ejecta into sunlight, it wouldn't matter if we hit an iceberg because we would never know it." For example, if the impact site is close to a high crater wall, the ejecta would have to travel far to get out of the wall's shadow and reach the sunlight above. And if the impactor hits a steep slope in the bottom of a shadowed crater, much of the ejecta would blast out sideways instead of upward toward the sunlight. So a good site would be relatively flat-bottomed — less than about 15° of slope — with a fluffy regolith free of large boulders or rubble that would blunt the blow.

Colaprete says that, so far, one of the best sites appear to be in a 17 km-across unnamed crater just west of Peary crater (88.6° N, 33.0° E), near the Moon’s north pole. "We've gone through essentially every possible launch date and picked a crater [for each date]," he says.

Above: The Moon's north pole. Each of the yellow dots marks a crater with possibly permanent shadows. According to a 2003 study, as much as 7,500 km2 around the lunar north pole could lie in perpetual shadow. [more]

Choosing impact sites must also take another factor into account: visibility from Earth. Hundreds of amateur and professional astronomers will join the LCROSS robotic orbiter in watching the crash.

The explosion itself will probably be hidden by the walls of the target crater. Instead, what astronomers will look for is the impact plume. An expanding cone of ejecta will rise more than 6 kilometers above the lunar surface and spread outward for about 40 km in every direction. Glistening in the sunlight, the debris is expected to shine like a 6th to 8th magnitude star—invisible to the human eye but an easy target for backyard telescopes.

Colaprete's team will time the impact so that it happens while the Moon is high in the sky at night in Hawaii. There, LCROSS scientists will observe the ejecta plume with the powerful Infrared Telescope Facility. But astronomers on the west coast of the U.S. and in Japan could be able to see the impact as well, depending on the precise impact time. "It really is going to turn into an international event," Colaprete says. "Everyone's going to be training their eyes on the impact to observe it."

Stay tuned to Science@NASA to find out how amateur astronomers can collaborate with LCROSS scientists to help make this historic search for water on the Moon a smashing success.

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Editor: Dr. Tony Phillips | Credit: Science@NASA

Strong Start Increases NOAA’s Confidence for Above-Normal Atlantic Hurricane Season

 

High resolution (Credit: NOAA)

In the August update to the Atlantic hurricane season outlook, NOAA’s Climate Prediction Center has increased the likelihood of an above-normal hurricane season and has raised the total number of named storms and hurricanes that may form. Forecasters attribute this adjustment to atmospheric and oceanic conditions across the Atlantic Basin that favor storm development - combined with the strong early season activity.

NOAA now projects an 85 percent probability of an above-normal season – up from 65 percent in May. The updated outlook includes a 67 percent chance of 14 to 18 named storms, of which seven to 10 are expected to become hurricanes, including three to six major hurricanes of Category 3 strength or higher on the Saffir-Simpson Scale. These ranges encompass the entire season, which ends November 30, and include the five storms that have formed thus far.

In May, the outlook called for 12 to 16 named storms, including six to nine hurricanes and two to five major hurricanes. An average Atlantic hurricane season has 11 named storms, including six hurricanes and two major hurricanes.

High resolution (Credit: NOAA)

“Leading indicators for an above-normal season during 2008 include the continuing multi-decadal signal – atmospheric and oceanic conditions that have spawned increased hurricane activity since 1995 – and the lingering effects of La Niña,” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center. “Some of these conditions include reduced wind shear, weaker trade winds, an active West African monsoon system, the winds coming off of Africa and warmer-than-average water in the Atlantic Ocean.”

Another indicator favoring an above-normal hurricane season is a very active July, the third most active since 1886. Even so, there is still a 10 percent chance of a near normal season and a five percent chance of a below normal season.

Hurricane Dolly on July 23, 2008.

High resolution (Credit: NOAA)

NOAA’s hurricane outlook is a general guide to the expected level of hurricane activity for the entire season. NOAA does not make seasonal landfall predictions since hurricane landfalls are largely determined by the weather patterns in place as a hurricane approaches.

Five named storms have formed already this season. Tropical Storm Arthur affected the Yucatan Peninsula in late May and early June. Bertha was a major hurricane and the longest-lived July storm (July 3-20) on record. Tropical Storm Cristobal skirted the North Carolina coastline. Dolly made landfall as a Category 2 hurricane at South Padre Island, Texas on July 25. And on August 5, Tropical Storm Edouard struck the upper Texas coast.

Atlantic water vapor animation.

Download as Quicktime [MP4] (Credit: NOAA)

“It is critical that everyone know the risk for your area, and have a plan to protect yourself, your family and your property, or to evacuate if requested by local emergency managers. Be prepared throughout the remainder of the hurricane season,” Bell said. “Even people who live inland should be prepared for severe weather and flooding from a tropical storm or a hurricane.”

The Atlantic hurricane season includes activity over the Atlantic Ocean, Caribbean Sea and Gulf of Mexico. The peak months of the season are August through October.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.

With Southern California’s earthquake in the news, here are some interesting facts and figures:

•

Earthquakes can trigger other natural disasters: landslides, flash floods, fires, avalanches, and tsunamis.

•

Each year in the U.S., an average of six magnitude 6 or higher and 57 magnitude 5 or higher earthquakes occur.

•

The largest recorded U.S. earthquake was magnitude 9.2 in Prince William Sound, Alaska, on March 28, 1964.

•

1812 along the New Madrid Fault in Missouri. The quakes were felt throughout the Eastern US.

The most widely felt series of earthquakes in the lower-48 states took place for three months between 1811 and

•

could be more devastating because the shaking would affect a larger area than a comparable quake in the

Western U.S. would. Additionally, population density is high in the East, and many buildings are not built to

withstand an earthquake.

While earthquakes are more common in the Western US, studies indicate that a severe quake in the Eastern U.S.

The Earthquake-Weather Myth

There is a common belief that earthquakes occur more frequently during hot and dry weather. Actually, scientists have

never found a correlation between weather and earthquake activity. Because earthquakes originate miles below

ground, they are not affected by weather occurring at the Earth's surface.

According to the US Geological Survey, there are 26 urban areas in the US at risk for significant shakes:

AK: Anchorage

CA: Fresno, Los Angeles, Sacramento, Salinas, San Diego, San

Francisco, Santa Barbara, Stockton-Lodi

ID: Boise

IN: Evansville

MA: Boston

MO: St. Louis

NM: Albuquerque

NV: Las Vegas, Reno

NY: New York

OR: Eugene-Springfield, Portland

PR: San Juan

SC: Charleston

TN: Chattanooga-Knoxville, Memphis

UT: Provo-Orem, Salt Lake City

WA: Seattle

Protecting Yourself during an Earthquake

Inside:

you are and try to brace yourself. If you are in bed, stay there and protect yourself with a pillow. Stay away from

windows, and stay inside until the shaking stops. A common myth is that you should head for a doorway -- In most

homes, doorways are no stronger than other areas, and swinging doors can cause injury. Take cover under a

strong piece of furniture, instead.

When the shaking begins, drop to the ground, take cover, and hold on. If you are unable to drop, stay where

Outside:

Drop to the ground and stay still until the shaking stops.

Find a clear area away from buildings, trees, streetlights, power lines, and other structures that may fall.

In a Car:

Pull over to a clear area, stop, and remain in your car with your seatbelt on.

Image: USGS

Plasma Bullets Spark Northern Lights

07.24.2008

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July 24, 2008: Duck! Plasma bullets are zinging past Earth.

That's the conclusion of researchers studying data from NASA's five THEMIS spacecraft. The gigantic bullets, they say, are launched by explosions 1/3rd of the way to the Moon and when they hit Earth—wow. The impacts spark colorful outbursts of Northern Lights called "substorms."

Right: A substorm of Northern Lights photographed from the window of an airplane over Hudson Bay, Canada, on Feb 27, 2008. Credit: Jeff Hapeman. [more]

"We have discovered what makes the Northern Lights dance," declares UCLA physicist Vassilis Angelopoulos, principal investigator of the THEMIS mission. The findings appear online in the July 24 issue of Science Express and in print August 14 in the journal Science.

The THEMIS fleet was launched in February 2007 to unravel the mystery of substorms, which have long puzzled observers with their unpredictable eruptions of light and color. The spacecraft wouldn't merely observe substorms from afar; they would actually plunge into the tempest using onboard sensors to measure particles and fields. Mission scientists hoped this in situ approach would allow them to figure out what caused substorms--and they were right.

The discovery came on what began as a quiet day, Feb 26, 2008. Arctic skies were dark and Earth's magnetic field was still. High above the planet, the five THEMIS satellites had just arranged themselves in a line down the middle of Earth’s magnetotail—a million kilometer long tail of magnetism pulled into space by the action of the solar wind.

Sign up for EXPRESS SCIENCE NEWS delivery That's when the explosion occurred.

A little more than midway up the THEMIS line, magnetic fields erupted, "releasing about 1015 Joules of energy," says Angelopoulos. "For comparison, that's about as much energy as a magnitude 5 earthquake."

Although the explosion happened inside Earth's magnetic field, it was actually a release of energy from the sun. When the solar wind stretches Earth's magnetic field, it stores energy there, in much the same way energy is stored in a rubber band when you stretch it between thumb and forefinger. Bend your forefinger and—crack!—the rubber band snaps back on your thumb. Something similar happened inside the magnetotail on Feb. 26, 2008. Over-stretched magnetic fields snapped back, producing a powerful explosion. This process is called "magnetic reconnection" and it is thought to be common in stellar and planetary magnetic fields.

The blast launched two "plasma bullets," gigantic clouds of protons and electrons, one toward Earth and one away from Earth. The Earth-directed cloud crashed into the planet below, sparking vivid auroras observed by some 20 THEMIS ground stations in Canada and Alaska. The opposite cloud shot harmlessly into space, and may still be going for all researchers know.

Above: An artist's concept of the THEMIS satellites lined up inside Earth's magnetotail with an explosion between the 4th and 5th satellites. [Larger image]

The THEMIS satellites were perfectly positioned to catch the shot.

"We had bulls-eyes on our solar panels," says THEMIS project scientist David Sibeck of NASA's Goddard Space Flight Center. "Four of the satellites were hit by the Earth-directed cloud, while the opposite cloud hit the fifth satellite." Simple geometry pinpointed the site of the blast between the 4th and 5th satellite or "about 1/3rd of the way to the Moon."

No damage was done to the satellites. Plasma bullets are vast, gossamer structures less dense than the gentlest wisp of Earth's upper atmosphere. They whoosh past, allowing THEMIS instruments to sample the cloud’s internal particles and fields without truly buffeting the satellite.

This peaceful encounter on the small scale of a spacecraft, however, belies the energy deposited on the large scale of a planet. The bullet-shaped clouds are half as wide as Earth and 10 times as long, traveling hundreds of km/s. When such a bullet strikes the planet, brilliant auroras and geomagnetic storms ensue.

Right: A collection of ground-based All-Sky Imagers (ASI) captures the aurora brightening caused by a substorm. Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio. [animation]

"For the first time, THEMIS has shown us the whole process in action—from magnetic reconnection to aurora borealis," says Sibeck. "We are finally solving the puzzle of substorms."

The THEMIS mission is scheduled to continue for more than another year, and during that time Angelopoulos expects to catch lots more substorms--"dozens of them," he says. "This will give us a chance to study plasma bullets in greater detail and learn how they can help us predict space weather."

"THEMIS is not finished making discoveries," believes Sibeck. "The best may be yet to come."

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Author: Dr. Tony Phillips | Credit: Science@NASA

Northern Wildfire Smoke May Cast Shadow on Arctic Warming

NOAA satellite image, June 30, 2004, showing wildfire smoke blanketing Alaska.

High resolution (credit: NOAA)

The Arctic may get some temporary relief from global warming if the annual North American wildfire season intensifies, according to a new study by researchers at the University of Colorado and NOAA.

Smoke transported to the Arctic from northern forest fires may cool the surface for several weeks to months at a time, according to the most detailed analysis yet of how smoke influences the Arctic climate relative to the amount of snow and ice cover.

"Smoke in the atmosphere temporarily reduces the amount of solar radiation reaching the surface. This transitory effect could partly offset some of the warming caused by the buildup of greenhouse gases and other pollutants," said Robert Stone, an atmospheric scientist with the university and NOAA Cooperative Institute for Research in Environmental Sciences (CIRES) and lead author of the study, which appears this week in the Journal of Geophysical Research.

How much solar energy is prevented from reaching the surface depends on the smoke's opacity, the elevation of the sun above the horizon, and the brightness of the surface, according to the study.

Stone and his research colleagues analyzed the short-term climate impact of numerous wildfires that swept through Alaska and western Canada in 2004. That summer, fires burned a record 10,000 square miles of Alaska's interior and another 12,000 square miles in western Canada.

A NOAA climate observatory near Barrow, Alaska, provided the data for the study. Smoke observed at Barrow was so thick that at times visibility dropped to just over one mile. The aerosol optical depth (AOD), a measure of the total absorption and scattering of solar radiation by smoke particles, rose a hundredfold from typical summer values.

Smoke in the atmosphere tends to cool the snow-free tundra while warming the smoke layer itself, the authors found. Smoke has an even greater cooling effect over the darker, ice-free ocean and less over bright snow.

"The heating of the smoke layer and cooling of the surface can lead to increased atmospheric stability, which in turn may keep clouds from forming," said Stone. "We think that this influence of smoke aerosol on clouds further affects the balance of radiation reaching the surface in the Arctic."

Research observatories as far away as Greenland and the Svalbard archipelago north of Norway also recorded elevated AOD values over several weeks during the 2004 summer, suggesting that the climate footprint of the North American wildfires was far-reaching. Smoke from the same fires also was observed as far south as the Gulf of Mexico.

To conduct their analysis, Stone and colleagues looked at how a range of smoky conditions might change the amount of solar radiation reaching the Earth’s surface. Models showed that the cooling caused by future forest fires would depend on the severity of the fire season and on the geographic dispersion of smoke.

The authors cautioned, however, that the full climate impact of Arctic aerosols, including smoke particles, is still not entirely clear. For one thing, smoke particles captured within clouds or deposited on snow may change the brightness of these objects, further affecting the amount of solar radiation absorbed by the surface.

Also, aerosols such as smoke affect the absorption and scattering not only of solar radiation, but also of longwave or thermal radiation within the atmosphere. The impact of aerosols on longwave radiation, which dominates at night and during the long, dark winter season in the Arctic, has yet to be quantified.

NOAA understands and predicts changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and conserves and manages our coastal and marine resources.

DESCENDING SPACE JUNK: Almost exactly one year ago, on July 23, 2007, International Space Station astronauts threw an obsolete, refrigerator-sized ammonia reservoir overboard. The 1400-lb piece of space junk has been circling Earth ever since and now, in July 2008, its orbit has decayed so much that it has become an easy naked-eye target for backyard sky watchers. The "Early Ammonia Servicer" (EAS for short) is almost as bright as the stars of the Big Dipper and growing brighter as it descends. Today's edition of

http://spaceweather.com displays photos of the EAS, which is expected to burn up in Earth's atmosphere in late 2008 or early 2009. Readers who wish to see the EAS with their own eyes should check the Simple Satellite Tracker for flyby times: http://spaceweather.com/flybys. Europeans are favored with flybys this week, North Americans next week.

The 2008 Perseid Meteor Shower

07.22.2008

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July 22, 2008: Mark your calendar: The 2008 Perseid meteor shower peaks on August 12th and it should be a good show.

"The time to look is during the dark hours before dawn on Tuesday, August 12th," says Bill Cooke of NASA's Meteoroid Environment Office at the Marshall Space Flight Center. "There should be plenty of meteors--perhaps one or two every minute."

Right: A Perseid meteor over Joshua Tree National Park in California, August 11, 2007. Credit: Joe Westerberg. [more]

The source of the shower is Comet Swift-Tuttle. Although the comet is far away, currently located beyond the orbit of Uranus, a trail of debris from the comet stretches all the way back to Earth. Crossing the trail in August, Earth will be pelted by specks of comet dust hitting the atmosphere at 132,000 mph. At that speed, even a flimsy speck of dust makes a vivid streak of light when it disintegrates--a meteor! Because, Swift-Tuttle's meteors streak out of the constellation Perseus, they are called "Perseids."

(Note: In the narrative that follows, all times are local. For instance, 9:00 pm means 9:00 pm in your time zone, where you live. )

Sign up for EXPRESS SCIENCE NEWS delivery Serious meteor hunters will begin their watch early, on Monday evening, August 11th, around 9 pm when Perseus first rises in the northeast. This is the time to look for Perseid Earthgrazers--meteors that approach from the horizon and skim the atmosphere overhead like a stone skipping across the surface of a pond.

"Earthgrazers are long, slow and colorful; they are among the most beautiful of meteors," says Cooke. He cautions that an hour of watching may net only a few of these at most, but seeing even one can make the whole night worthwhile.

A warm summer night. Bright meteors skipping overhead. And the peak is yet to come. What could be better?

The answer lies halfway up the southern sky: Jupiter and the gibbous Moon converge on August 11th and 12th for a close encounter in the constellation Sagittarius: sky map. It's a grand sight visible even from light-polluted cities.

For a while the beautiful Moon will interfere with the Perseids, lunar glare wiping out all but the brightest meteors. Yin-yang. The situation reverses itself at 2 am on Tuesday morning, August 12th, when the Moon sets and leaves behind a dark sky for the Perseids. The shower will surge into the darkness, peppering the sky with dozens and perhaps hundreds of meteors until dawn.

Above: The eastern sky viewed during the hours before sunrise on Tuesday, Aug. 12, 2008.

For maximum effect, "get away from city lights," Cooke advises. The brightest Perseids can be seen from cities, he allows, but the greater flurry of faint, delicate meteors is visible only from the countryside. (Scouts, this is a good time to go camping.)

The Perseids are coming. Enjoy the show!

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Author: Dr. Tony Phillips | Credit: Science@NASA

NASA works to improve short-term weather forecasts

07.18.2008

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July 18, 2008: Sometimes seconds count. If a furious, tornado-spitting thunderstorm was bearing down on your home town, a few moments might make all the difference in the world.

Will McCarty, a graduate student at the National Space Science and Technology Center, is working with data from NASA's Aqua satellite to improve short-term weather predictions--the kind that could help you dodge that thunderstorm.

Above: Severe weather over DeWitt, Michigan, on June 14, 2008. Photo credit and copyright: Daniel O'Malley.

Guided by his NASA mentor, Gary Jedlovec, McCarty has already learned how to improve 48-hour forecasts by 3 hours. "That may not sound like a big deal, but tell that to someone who escaped a weather disaster by the skin of their teeth," says McCarty.

They accomplished the improvement by entwining measurements from Aqua's Atmospheric Infrared Sounder (AIRS), into weather models. To understand how AIRS works its magic, let's first take a look at how forecasts are made:

Sign up for EXPRESS SCIENCE NEWS delivery Twice a day, all over the world, weather balloons measure temperature, wind, air pressure and humidity. These balloons sample the lowest 7 to 10 miles of Earth's atmosphere, where weather happens. More measurements are made by surface observing stations, aircraft, and weather radars. All these data form a "snapshot" of the weather over the land at one point in time, every 12 hours.

Next, the measurements are plugged into forecast models--computer-coded equations that describe the interactions among the weather-influencing variables mentioned above, plus others. A forecaster interprets the model output to make his local weather prediction.

Sometimes lives ride on this mundane sounding process.

"The better we make the model output, the more the forecaster can trust it and use it as a tool for forecasting, and the more accurate forecasts the public receives," says McCarty.

AIRS improves the model output by improving its input: Riding on NASA's Aqua spacecraft and viewing the atmosphere through nearly 2,400 different spectral channels, AIRS creates an accurate global 3-D map of atmospheric temperature, water vapor, clouds and greenhouse gases.

Right: Will McCarty of the National Space Science and Technology Center in Huntsville, Alabama. [more]

"AIRS has finer resolution than previous instruments, so it can make more detailed measurements," says McCarty. "This makes analyses sharper, which improves the forecasts based on them."

McCarty and Jedlovec are most interested in AIRS infra-red "radiances," i.e., measurements of thermal energy emitted by the Earth's surface and atmosphere. The researchers look at radiances because they provide large scale measurements of the temperature and water vapor patterns in the atmosphere.

"Radiance measurements, in general, allow the observation of many places, particularly over the oceans, that are sparsely measured directly by traditional means, if at all," explains McCarty. "AIRS gives us the best picture of the vertical temperature and moisture structures ever made from space."

AIRS' claim to fame, then, is its capacity to increase both the area of Earth's atmosphere measured and the detail of those measurements.

Above: A typical AIRS infra-red weather snapshot. This is typhoon Nakri, which Aqua flew over on May 28, 2008. [more]

What's the next step? "Dealing with clouds," says McCarty. "Infrared energy doesn't penetrate clouds well. When clouds are around, the instrument is really only seeing the tops of clouds."

When clouds are low, however, there's still some good data from the air above them because most of the atmosphere is still being measured. These data have been wasted up to now – thrown out in the bathwater along with all the other cloud-contaminated data.

McCarty is now working on an algorithm to identify which channels are truly useless and which are valid. His method will help identify what is good, useful data and increase the amount of data collected, making even better forecasts possible. He will soon plug his data into a forecast model to find out just how much better.

A 3-hour improvement may be just the beginning.

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Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA

NOAA: Eighth Warmest June on Record for Globe

The combined average global land and ocean surface temperatures for June 2008 ranked eighth warmest for June since worldwide records began in 1880, according to an analysis by NOAA’s National Climatic Data Center in Asheville, N.C. Also, globally it was the ninth warmest January – June period on record.

Global Highlights

• The combined global land and ocean surface temperature for June 2008 was 60.8 degrees F, which is 0.9 degrees F above the 20th century mean of 59.9 degrees F.

• Separately, the global land surface temperature was 57.2 degrees F, which is 1.3 degrees F above the 20th century mean of 55.9 degrees F.

• The global ocean surface temperature was 62.2 degrees F, which is 0.7 degrees F above the 20th century mean of 61.5 degrees F.

• For the January – June period, the combined global land and ocean surface temperature was 57.1 degrees F, which is 0.8 degrees F about the 20th century mean of 56.3 degrees F.

Other Highlights

• Northern Hemisphere Arctic sea ice extent for June 2008 ranked third lowest for June since records began in 1979. Southern Hemisphere Antarctic sea ice extent for June 2008 was above the 1979-2000 mean, ranking as the second largest June extent.

• El Niño-Southern Oscillation conditions transitioned to a neutral phase during June.

• Torrential rain lashed southern China from June 7-18. These were followed by more heavy rain from typhoon Fengshen late in the month. The downpours caused widespread floods and affected more than five million people. June 2008 was the wettest month ever for Hong Kong, Guangzhou, and Macao based on records that began in 1884. 

What's Wrong with the Sun? (Nothing)

07.11.2008

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Stop the presses! The sun is behaving normally.

So says NASA solar physicist David Hathaway. "There have been some reports lately that Solar Minimum is lasting longer than it should. That's not true. The ongoing lull in sunspot number is well within historic norms for the solar cycle."

This report, that there's nothing to report, is newsworthy because of a growing buzz in lay and academic circles that something is wrong with the sun. Sun Goes Longer Than Normal Without Producing Sunspots declared one recent press release. A careful look at the data, however, suggests otherwise.

But first, a status report: "The sun is now near the low point of its 11-year activity cycle," says Hathaway. "We call this 'Solar Minimum.' It is the period of quiet that separates one Solar Max from another."

Above: The solar cycle, 1995-2015. The "noisy" curve traces measured sunspot numbers; the smoothed curves are predictions. Credit: D. Hathaway/NASA/MSFC. [more]

During Solar Max, huge sunspots and intense solar flares are a daily occurance. Auroras appear in Florida. Radiation storms knock out satellites. Radio blackouts frustrate hams. The last such episode took place in the years around 2000-2001.

During Solar Minimum, the opposite occurs. Solar flares are almost non-existant while whole weeks go by without a single, tiny sunspot to break the monotony of the blank sun. This is what we are experiencing now.

Sign up for EXPRESS SCIENCE NEWS delivery Although minima are a normal aspect of the solar cycle, some observers are questioning the length of the ongoing minimum, now slogging through its 3rd year.

"It does seem like it's taking a long time," allows Hathaway, "but I think we're just forgetting how long a solar minimum can last." In the early 20th century there were periods of quiet lasting almost twice as long as the current spell. (See the end notes for an example.) Most researchers weren't even born then.

Hathaway has studied international sunspot counts stretching all the way back to 1749 and he offers these statistics: "The average period of a solar cycle is 131 months with a standard deviation of 14 months. Decaying solar cycle 23 (the one we are experiencing now) has so far lasted 142 months--well within the first standard deviation and thus not at all abnormal. The last available 13-month smoothed sunspot number was 5.70. This is bigger than 12 of the last 23 solar minimum values."

In summary, "the current minimum is not abnormally low or long."

The longest minimum on record, the Maunder Minimum of 1645-1715, lasted an incredible 70 years. Sunspots were rarely observed and the solar cycle seemed to have broken down completely. The period of quiet coincided with the Little Ice Age, a series of extraordinarily bitter winters in Earth's northern hemisphere. Many researchers are convinced that low solar activity, acting in concert with increased volcanism and possible changes in ocean current patterns, played a role in that 17th century cooling.

For reasons no one understands, the sunspot cycle revived itself in the early 18th century and has carried on since with the familiar 11-year period. Because solar physicists do not understand what triggered the Maunder Minimum or exactly how it influenced Earth's climate, they are always on the look-out for signs that it might be happening again.

The quiet of 2008 is not the second coming of the Maunder Minimum, believes Hathaway. "We have already observed a few sunspots from the next solar cycle," he says. (See Solar Cycle 24 Begins.) "This suggests the solar cycle is progressing normally."

What's next? Hathaway anticipates more spotless days1, maybe even hundreds, followed by a return to Solar Max conditions in the years around 2012.

Stay tuned to Science@NASA for updates.

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Author: Dr. Tony Phillips | Credit: Science@NASA

NASA to Attempt Historic Solar Sail Deployment

 

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"Hold your hands out to the sun. What do you feel? Heat, of course. But there's pressure as well – though you've never noticed it, because it's so tiny. Over the area of your hands, it only comes to about a millionth of an ounce. But out in space, even a pressure as small as that can be important – for it's acting all the time, hour after hour, day after day. Unlike rocket fuel, it's free and unlimited. If we want to, we can use it; we can build sails to catch the radiation blowing from the sun."1

These words were spoken not by a NASA scientist but by a fictional character – John Merton – in Arthur C. Clarke's short story The Wind from the Sun. If all goes well, Merton's prophetic words are about to become fact.

NASA researchers, thinking "out of the box" (or maybe "out of the rocket") have long dreamed of the possibility of sailing among the planets with sails propelled by sunlight instead of by wind. Except in works of fiction, though, no one has yet successfully deployed such a sail anywhere beyond Earth.

Right: An artist's concept of a sailing ship and a solar sail.

"There's a first time for everything," says Edward "Sandy" Montgomery of NASA's Marshall Space Flight Center.

Montgomery's team and a team from Ames Research Center (led by Elwood Agasid) hope to make history this summer by deploying a solar sail called NanoSail-D. It will travel to space onboard a SpaceX Falcon 1 rocket, scheduled for launch from Omelek Island in the Pacific Ocean during a window extending from July 29th to August 6th (a back-up extends from August 29th to September 5th).

Sign up for EXPRESS SCIENCE NEWS delivery "NanoSail-D will be the first fully deployed solar sail in space, and the first spacecraft to use solar pressure as a primary means of attitude control or orbital maneuvering," says Montgomery, who is NanoSail-D's payload manager.

"We are always on the lookout for opportunities. Ames owns a slot on the Falcon 1 launch and asked us if we wanted to go along. We said, 'Yes!' We'll use the Poly Picosatellite Orbital Deployer, or P-POD, developed by the University of California Polytechnic Institute to deploy our sail."

A few years ago, the Planetary Society attempted a mission like NanoSail-D called Cosmos I, but the launch vehicle failed and destroyed the undeployed spacecraft. Montgomery and team believe that NanoSail-D, however, will unfurl four gossamer wings from its pod in the blackness of space like a butterfly from a cocoon: movie.

"The structure is made of aluminum and space-age plastic," says Montgomery. "The whole spacecraft weighs less than ten pounds. We carry it around in a special suitcase -- airplane carry-on luggage size." Fully opened, the kite-shaped sail spreads out to about 100 square feet of light-catching surface.

Above: The Huntsville-based NanoSail-D team stands with the fully deployed sail at ManTech SRS technologies on April 16, 2008, after the successful deployment test.

"A success would be huge for the future of space exploration," Montgomery believes.

Why so important? Solar sails could extend our reach as far as our dreams. Because there's no friction in space, once a solar sail starts moving, it can go on forever. Indeed, long after a rocket would run out of gas and begin to coast, a solar sailship could still be accelerating, achieving speeds much faster and covering distances far greater than any rocket. No rocket in existence could carry enough fuel to reach the outer solar system in as short a time. And like a marine sail, a solar sail could also bring you home. You could use the solar sail to tack your vessel, making it travel "against the wind," back to Earth.

"It's not so much about how far a sail will go compared to a rocket; the key is how fast," says Montgomery. "The Voyagers have escaped the solar system, and they were sent by rockets, but it's taken more than three decades to do it. A sail launched today would probably catch up with them in a single decade. Sails are slower to get started though. So, for example, between the Earth and the moon, rockets might be preferred for missions with a short timeline. It's a trip of days for rockets, but months for a solar sail. The rule of thumb, therefore, would be to use rockets for short hops and solar sails for the long hauls."

Right: University of Alabama research technician Doug Huie holds the future in his hands. Folded-up, NanoSail-D occupies a space no bigger than a bread box.

All of this may sound like speculation, but NanoSail-D could show that solar sails are truly feasible. And there's an added bonus to this technology demo:

"Currently, micro-satellites in orbit above a few hundred kilometers can stay in orbit for decades after completing their mission," explains Montgomery. "This creates an orbital debris collision risk for other spacecraft. NanoSail-D will demonstrate the feasibility of using a drag sail to decrease the time satellites clutter up Earth's orbit. Although our sail looks like a kite, it will act like a parachute (or like a drag sail) in the very thin upper atmosphere around Earth. It will slow the spacecraft and make it lose altitude, re-enter the Earth's atmosphere and burn off in a relatively short period of time. A drag sail is a lighter alternative to carrying a propulsion system to de-orbit a satellite."

And finally, the question everyone wants answered: What does D stand for?

"We chose the 'D' in the name, not because it came after models A, B, and C, but because it can stand for demonstrate, deploy, drag, and/or de-orbit," says Montgomery.

Soon, 'D' may stand for something new: "DID IT!"

Check Science@NASA post-launch and the meaning will be revealed.

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Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA