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Star Teacher February 2008
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Total Lunar Eclipse!
On February 20th a very special event will be taking place in the night sky: a full lunar eclipse. Last August there was a lunar eclipse but not everyone was able to see it. This year, though, people everywhere in the United States will be able to watch the moon as it is eclipsed, even people in Maine! A lunar eclipse is a rare event. Usually they only happen twice a year, and not everybody can see them when they do happen. |
If you’ve ever made shadow puppets with a flashlight you already know a little of how an eclipse works. The flashlight is a source of light, and when your fingers go in front of that light it makes a shadow. The same thing happens to the sun and the Earth. Our sun is the biggest flashlight in our solar system. It’s so big that it makes the Earth give a shadow out into space (just like your fingers make shadow puppets). There’s one more factor in a lunar eclipse: the moon. While the moon looks like it’s giving off its own light in the night sky, it is actually only reflecting light from the sun. If the light from the sun was hidden, the moon would not light up the sky. Every month the moon orbits around the Earth and its shadow. Most of the time the moon goes either above or below the shadow of the Earth, but every once in a while it goes inside the shadow. When it is inside the shadow, light from the sun is cut off. The moon has no light to reflect so it appears dark in the sky. This is a lunar eclipse. |
A lunar eclipse is a beautiful thing to watch. Bit by bit the moon turns dark, almost as if someone is taking bites out of it! When the shadow reaches all the way across the moon, though, it does not go dark completely. Instead it often turns a deep orange or red color. The Earth’s shadow is not big enough to completely cover the moon. Imagine you were on the moon during a lunar eclipse and could look back on Earth. The Earth would not look completely dark. Instead, there would be a ring of light around it. This light is all the sunrises and sunsets happening at that moment. The light from those sunrises and sunsets glows red, giving the moon its strange but beautiful color.
A total lunar eclipse is rare and beautiful. Don’t forget to go outside on February 20th to see this special event. And if you are int he Orono area, the Jordan Observatory on the Orono campus will host a public Eclipse Party from 8:30PM to midnight.
NASA Official Eclipse Site ... Outstanding LPI Eclipse Activities ....
Click here for a printer-friendly, hands-on activity about moon phases and eclipses you can do with your students. (Adobe Acrobat Reader Req'd) |
Timing of February Eclipse
| 8:42pm |
Reaches umbra |
| 10:00pm |
Fully eclipsed |
| 10:51pm |
Begins to leave umbra (no longer fully eclipsed) |
| 12:09am |
Completely exits umbra |
School Vacation Star Shows
The Jordan Planetarium added special showings to its schedule for the children on vacation this February 18-22 and their families. For a complete schedule visit the Mission section of GalaxyMaine.com and download a printable bookmark for your class. (Acrobat Req'd)
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What's Happening In the Sky This February?
| 3 |
Conjunction of moon, Venus and Jupiter – Our moon and the planets Jupiter and Venus will create a beautiful image as they meet in the night sky. As the month goes on, however, the planets will move farther and farther away from each other. |
| 7 |
New Moon |
| 20/21 |
Full moon/Total lunar eclipse -
Take some time to watch this rare and special event! Read more about it in this month’s Star Teacher. |
| 24 |
Saturn in opposition -
Opposition happens when a planet, the sun and the Earth form a straight line. The best time to see a planet in the night sky is when it is in opposition. This month, Saturn will rise in the east when the sun sets, travel across the sky all night, and set in the west as the sun rises |
| 29 |
Leap Year day added - The Earth takes a little longer than 365 days to go around the sun. In order to keep our calendars accurate we add one day to our year every four years. If we didn’t, after a few hundred years we’d be celebrating Christmas in the summertime! We add the extra day to February, the shortest month of the year. |
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Where Are the Viewable Planets?
Venus |
Begins the month near Jupiter about two hours before sunrise. As the month goes on, though, the two planets will grow further and further apart as Venus rises later and later each day. By the end of the month Venus will rise only an hour before the sun does. |
Mars |
Has stopped its retrograde motion. Can be found bright and high in the sky early in the evening at the beginning of the month, but grows dimmer as the month gets older. By the end of the month it will be gracing the eastern sky. |
Jupiter |
Begins the month near Venus about two hours before sunrise. Over the course of the month it will rise higher in the sky and grow brighter and brighter. By the end of the month it will shine brightly in the morning sky about three hours before sunrise. |
Saturn |
Will be highly visible this month, especially on the 24 th when it is in the sky all night long. Look for the ringed planet in the constellation of Leo. It will shine brightly next to Regulus, the heart of Leo the lion. |
This month's constellation: Leo
This month’s lunar eclipse will happen near the constellation of Leo. You can also find the planet Saturn in Leo this month. Leo is a zodiac constellation, which means it’s a constellation that the sun travels through in our sky. If you can find the big dipper you can find Leo. All you have to do is draw a straight line down from the cup of the big dipper (imagine you’re hitting a spoon on a table). The cup of the big dipper will hit the head of a ferocious Lion. That lion is Leo! Many people think Leo looks like a backwards question mark in the sky: a bright hook of stars and a bright point at the bottom made by the star Regulus. In the wintertime you can find Leo in the east early in the evening. |
Leo can be found in Greek mythology in the story of the great hero Hercules. In this myth Leo is called by a different name: the Nemean Lion. This lion came to the Earth from the moon. Its skin and fur were so strong that it could not be killed by swords or bow and arrows. The Nemean Lion was not a friendly animal. In fact, it caused so much trouble that the king asked Hercules to kill it. Hercules did so by wrestling him. From that day on he wore the lion’s skin as armor and the lion was put in the sky to remind us of Hercules’s great deed.
Advanced astronomical information is available at SEDS. |
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February Anniversaires
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15: Galileo’s Birthday – Galileo Galilei is an astronomer from the 1600s. He was a very curious man, especially when it came to the night sky. This curiosity led him to be the first person to look at the sky through a telescope. Over time Galileo discovered many new things about the sky. He was the first person to realize that Jupiter has moons and that the sun has spots on it. 2009 will be the 400 th anniversary of when Galileo first used his telescope. Because of this 2009 has been declared the International Year of Astronomy. Keep an eye out for more information about this exciting time. |
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18: Pluto Discovered – Because it is so small and far away, Pluto was not discovered until 1930. A scientist named Percival Lowell noticed that Uranus’s and Neptune’s orbits acted a bit strange. The only explanation for this would be another planet beyond Neptune’s orbit. After a long search this planet was found. It was named Pluto after the keeper of the underworld in Roman mythology. Until recently Pluto was thought to be a planet. In 2006 scientists decided that the farthest planet was different enough from the rest of the planets in the solar system to deserve its own category. Now Pluto is known as a dwarf planet. |
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19: Copernicus’s Birthday – Copernicus was an astronomer who was born in 1473. We remember him today because he had some interesting ideas about how our solar system worked. Before Copernicus scientists thought that the Earth was the center of the solar system. The sun, all the planets and all the stars supposedly rotated around it. Copernicus had a different idea. He said that instead of the Earth being the center of the solar system the sun was. People didn’t believe him at first, but as time went on and as science became more advanced it became clear that he was right. |
Space Exploration Continues Today
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It has been almost forty years since man first walked on the moon. Since then it may seem as though science has moved on to other things. While Mars, Pluto, and deep space objects have been popular headlines, missions to our closest neighbor in space are still going strong. |
There are two major moon missions happening right now. The first is the Selene mission. Run by the Japanese space agency, this mission is sending an orbiter to the moon in order to make maps of its surface. By doing this scientists hope to find out more about how the moon was made and to develop new technology for further moon exploration. China also has a current moon mission: Chang’e-1. This mission will hopefully find new information about the moon’s surface, including how deep the soil on its surface (called regolith) goes. Chang’e-1 will also make maps of the moon. (Visit an English language version of the Japanese site , or Chinaview's Mission Report)
The exploration of the moon is an endeavor in which scientists all over the world are participating. There are many possibilities that can come from these and future moon missions. With the knowledge gained we may be able to go back to the moon and establish a human presence there. The moon could become a launching point from which other space explorations can start. Although the moon may seem like a familiar face in the sky, we on Earth have only just begun exploring it.
Continue your own exploration of the moon this February in the Jordan Planetarium show “Moon Shadows.”
For more information on the Selene and Chang'e-1 missions, visit Nasa's moon exploration page |
The moon isn’t the only rocky body to be getting a lot of attention these days. Nasa’s Messenger mission has just sent back new pictures of a side of Mercury no one has seen before. The first image the Messenger sent back to Earth after its first flyby was quickly released to the internet so anyone can join in this historic first look. The Messenger (short for MErcury Surface, Space ENvironment, GEochemestry, and Ranging) spacecraft is the first mission sent to orbit Mercury, and is the first spacecraft to do a fly-by of the planet since Mariner 10 did in 1975.
Messenger’s mission is to answer questions about Mercury’s composition and geologic history. Although it’s the smallest planet it’s also the densest, has the oldest surface, and has the largest daily changes in temperature. Scientists hope that by examining these extremes (along with learning more about its magnetic field, core, and poles), more can be learned about how Mercury and other terrestrial planets, including Earth, were formed.
Previous missions to Mercury resulted in pictures of only one side of the planet. On January 14th, though, Messenger became the first to see Mercury’s other side. The resulting picture contained a few surprises. Just like the side of the planet previously seen, this side showed a very cratered surface. On the upper right the Caloris basin can be seen. This basin is one of the largest basins in the solar system, and perhaps one of the youngest. This picture provides the first view of the basin in its entirety. |
| Much more is expected from the Messenger spacecraft in the coming years. Two more fly-bys are planned for 2008 and 2009, and in 2011 the spacecraft will insert itself into orbit around Mercury. For more information about Messenger's current and future missions and high quality Mercury pictures, visit the Messenger Website. |
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