Volcanos are not just found on Earth
It wasn’t too long ago that we believed volcanoes were unique to the Earth. Then, in about 1980, a young, member of NASA’s Voyager navigation team named Linda Morabito saw a plume on the edge of Jupiter’s moon, Io. This was the discovery of the first extraterrestrial volcanic activity. We now have a 30-year record of the volcanoes on Io, one of which has been active for 18 years. For more on Io’s volcanoes, go to http://apod.nasa.gov/apod/astropix.html.
Although this was the first active volcano known, there are many examples of extinct volcanoes in our neighborhood. The moon, of course, is the nearest example. In fact, samples returned by the Apollo astronauts helped settle the debate about whether the craters on the moon are the tops of extinct volcanoes or the result of meteoric impacts.
Even though the surface of Venus is hidden by thick clouds, spacecraft using radar have been able to image its surface and we know it is about 90 percent covered with volcanic material. In fact, there is speculation Venus may have active volcanoes, though we have no direct evidence yet.
Mars is another favorite of volcano lovers, boasting the largest mountain in the solar system. Olympus Mons is 24 km (15 miles) high and would cover the state of Arizona. Whereas Mars was once volcanically active, it shows no signs of current activity.
Volcanoes also come in different flavors. The ones on Io mentioned earlier, spew liquid sulfur which settles on the surface as frozen sulfur dioxide “snow.” One of Saturn’s moons, Enceladus, sports cryovolcanoes with huge icy plumes. And on Triton, a frozen moon of Neptune, can be found volcanoes driven by sunlight that that vaporizes the icy nitrogen near the surface causing it to explode into space forming giant plumes.
It just goes to show that even some things found here on Earth, can also be found up in the sky.
This month in history:
June 3: Charles “Pete” Conrad born, 1932
June 10: Mars rover “Spirit” launched , 2003
June 16: Valentina Tereshkova first (and only solo) woman in space,1963
June 18: Sally Ride becomes first American woman in space, 1983
June 30: Tunguska impact (probably a comet fragment) flattens hundreds of miles of Siberian forrest, 1908
Here are this month’s viewing highlights:
Planets this month: Venus continues to dazzle western sky at dusk. See it near the crescent moon on the 14th and M44 on the 20th. Look toward the south for Mars and Saturn. Jupiter is high in southeast at dawn.
June 1: New moon.
June 4-5: Look west to see the crescent Moon to the left of Castor and Pollux 1 hour after sunset.
June 8: First quarter moon.
June 14: Moon left of Antares in south.
June 15: Full moon.
June 21: Summer Solstice 1:16 p.m. EDT.
June 23: Last-quarter moon
June 28: Look toward the eastern horizon 45 minutes before dawn. From the top down, look for the Plieades, crescent moon, Mars and Aldebaran.