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Published on Aug 20, 2012


August 19, 2012
Sagittarius, the archer, wheels low across the southern sky on summer evenings. Most modern skywatchers look for a group of stars that form the shape of a teapot floating through the hazy band of the Milky Way

August 20, 2012
The Milky Way arches high overhead tonight. You can see it if you escape from city light pollution. But even from the city, you can see the Milky Way's position, which is marked by the bright constellations Scorpius, Cygnus, and Cassiopeia

Volcanoes are a kind of opening that are found on the surface of the earth. Through this opening occur large eruptions of ash, molten rock, along with some gases that are found beneath the surface of the earth. There are various types of volcanoes that are seen not only on the Earth, but also on Mars, and the moons of Jupiter and Saturn

Based on their activity, volcanoes are classified as active - regular eruption; dormant - eruption in olden days but now inactive; extinct - volcanoes that may not erupt again

Located in the basin of the Pacific Ocean is an area called the Pacific Ring of Fire. This region is subjected to a large number of earthquakes and volcanic eruptions. The Ring of Fire is home to 452 volcanoes and 75% of the world's active and dormant volcanoes.
Volcanic eruptions are one of Earth's most dramatic and violent agents of change

Not only can powerful explosive eruptions drastically alter land and water for tens of kilometers around a volcano, but tiny liquid droplets of sulfuric acid erupted into the stratosphere can change our planet's climate temporarily. Eruptions often force people living near volcanoes to abandon their land and homes, sometimes forever. Those living farther away are likely to avoid complete destruction, but their cities and towns, crops, industrial plants, transportation systems, and electrical grids can still be damaged by tephra, ash, lahars, and flooding.

Fortunately, volcanoes exhibit precursory unrest that if detected and analyzed in time allows eruptions to be anticipated and communities at risk to be forewarned with reliable information in sufficient time to implement response plans and mitigation measures.

The lower 48 states in the U.S. have about 40 volcanoes that we think have had very recent activity, so they must be considered as active volcanoes. In Alaska, the number is more like 60. When we talk about whether a volcano is active or potentially a threat, it is important to look at the past ten years. Most of the important eruptions and disasters have happened at mountains that were not even recognized as being volcanoes.

The most important volcano in the U.S. is probably Rainier, which is not showing signs of activity but has produced very large eruptions. The danger is many people live close to Rainier.

The biggest volcano in the world is probably Mauna Loa, in Hawaii. It rises off of the seafloor to 13,000 feet above sea level or about 29,000 feet above the seafloor. Another huge volcano is Mt. Etna on the island of Sicily, in Italy.

A volcano is a mountain that opens downward to a pool of molten rock below the surface of the earth. When pressure builds up, eruptions occur.

The danger area around a volcano covers about a 20-mile radius

Fresh volcanic ash, made of pulverized rock, can be harsh, acidic, gritty, glassy and smelly. The ash can cause damage to the lungs of older people, babies and people with respiratory problems.

Volcano eruptions have been known to knock down entire forests.

An erupting volcano can trigger tsunamis, flash floods, earthquakes, mudflows and rockfalls.

Active volcanoes in the U.S. are found mainly in Hawaii, Alaska, California, Oregon and Washington, but the greatest chance of eruptions near areas where many people live is in Hawaii and Alaska.

Even though the volcanic eruption of Eyjafjallajökull in Iceland was relatively small, the ash cloud that was produced disrupted European air travel for six days in April 2010. The eruption created the highest level of air travel disruption World War II.

Crater Lake in Oregon formed from a high volcano that lost its top after a series of tremendous explosions about 6,600 years ago.

New Activity/Unrest: | Monowai Seamount, Kermadec Islands (SW Pacific) | Soufrière Hills, Montserrat | Tongariro, North Island (New Zealand) | White Island, New Zealand
Ongoing Activity: | Batu Tara, Komba Island (Indonesia) | Cleveland, Chuginadak Island | Fuego, Guatemala | Galeras, Colombia | Karymsky, Eastern Kamchatka (Russia) | Kilauea, Hawaii (USA) | Nevado del Ruiz, Colombia | Popocatépetl, México | Reventador, Ecuador | Sakura-jima, Kyushu | Shiveluch, Central Kamchatka (Russia) | Soputan, Sulawesi | Tungurahua, Ecuador

Traffic Report on 19 August '12
Two objects are reported traveling inside ten lunar distances of our planet today. 2012 PZ17 is outbound from 5.64 to 6.33 LD and 2012 PD20 from 9.72 to 9.98 LD.


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