Leaping Into an Extra Day

February 28, 2008

I was going to write a nice, detailed article about Leap Day (and Leap Years) tomorrow, but I see that Phil Plait, astronomer and owner of Bad Astronomy (plus an excellent science writer) had beaten me to it, and in much more detail than I was planning on.

So head on over to BadAstronomy.com and read his words of wisdom.


The Universe (Unexplained Mysteries)

February 26, 2008

The next episode of the amazing series The Universe continues tonight. The new episode is called “Unexplained Mysteries.” Here’s a preview…

Delve into the myths, misconceptions, truths and amazing mysteries of our unique universe. Could life exist on Mars? Is time travel possible and does Einstein’s theory of relativity support it? Is there a companion dark star to our sun and could it pose a threat to earth? Learn about the spark that lit the big bang. Take a journey from science fiction that predicted all these things, to the scientific reality of what they mean to us in the ever-changing universe.

The Universe is so expansive that there are unexplained mysteries just begging to be explored and understood, and as long as there are inquisitive minds, the unexplained can be the explained.

Check local listings for the time of the show.


Saturn Satisfaction

February 24, 2008

As the year goes by, the seasons change, and the earth goes around the sun in its orbit, the patterns in the sky shift positions night by night. Constellations rise earlier and earlier; the winter constellations are now giving way to spring ones.  And traveling along in those constellations are “wandering stars” that we now know as planets.

Right around sunset this week a bright, pale-gold point of light rises in the eastern sky, hitching a ride in the stars of the constellation Leo. It’s the great ringed jewel of our solar system, Saturn.

On the 24th, Saturn is at “opposition” which means that it is opposite the sun relative to us here on earth. As seen from above, earth would be between the Sun-Saturn line of sight. So as the sun sets in the west, Saturn rises in the east. It is basically the same principle as with other planets which are at opposition, and also when our own moon is at it’s full phase. Last week’s lunar eclipse was a fine example, as the moon rose just a few minutes before the sun set in the west.

As the planets travel in their own orbits around the sun, they seem to follow the stars as they rises earlier and earlier each night, but at a different speed, and at times, different directions. This is directly related to our position on the earth, relative to the planet and the background constellations. Sometimes a planet seems to stop, back up, and then go forward again. That is called retrograde motion.

With Saturn at opposition this week, if the skies are clear you can see it the entire night, and at midnight is will be nearly straight overhead, not far from the star Regulus in the constellation Leo (graphic).  And then, as the days and weeks go by, Saturn will rise earlier and earlier, until later this summer when it is rising so close to the sun it cannot be seen.

However, in the meantime, the ringed planet takes command of the night skies and, if you are fortunate to see it through a telescope, is a wonderful sight as it shows off its ring system and moons. The rings look a little narrower this year, and that is due to the position of Saturn in its orbit relative to the tilt of the Earth’s axis (and our own orbit). Every 14.7 years (Saturn orbits the Sun once every 29.4 years) the Earth crosses the “ring plane” of Saturn, and the rings seem to disappear from view for earthbound observers. That will happen again in September 2009, so this year will be the last time until 2010 to see the rings with any detail.

With now through July being the prime Saturn observing season this year, it will be a prominent featured object at the public nights at the Veen Observatory this year.

So if it is clear, go out and take a look at the solar system’s Lord of the Rings.


February’s Full Moon

February 20, 2008

The full moon for February takes place tonight at 10.30pm EST. And guess what? There just happens to be a lunar eclipse at the time!

The full moon for February is called the Full Snow Moon, as snow seems to fall the heaviest during this time of year, and it’s hard to get around. If it’s clear tonight (and it looks like it will be) go outside – but dress warm – and see the “snowy moon” as if turns a warm, reddish color during the eclipse.And if you view the eclipse, we would love to hear your reactions to it.

The Universe (Constellations)

February 19, 2008

The next episode of the amazing series The Universe continues tonight. The new episode is called “Constellations.” Here’s a preview…

A constellation is a group of stars that are connected together to form a figure or picture. These star pictures help organize the night sky and provide a useful tool for astronomers even today. Explore some of the 88 official constellations and learn about some of the highlights of each–like the star that’s due to go supernova in the constellation Orion. Discover the 13th zodiac sign that no one talks about, and find out why Polaris, the North Star, will one day have to surrender its title.

One of the things we do at our observatory during public nights is point out the constellations to the visitors. Did you know that if you know just a bit of the night sky, you can find out which direction you are facing, and where you are on the Earth?

Check local listings for the time of the show (and visit our observatory this year to find out more about the figures in the sky).


A Cold and Snowy Eclipse of the Moon

February 18, 2008

If the skies manage to clear Wednesday night, there will be a spectacular sight to behold: a total eclipse of the moon. And let’s hope for clear skies – the next total lunar eclipse for us isn’t until December 2010!

The last two lunar eclipses from here weren’t all that well timed for us here in Michigan. The eclipse of March 2007 took place as the moon was rising (and we didn’t see it because of the cloud cover that permanently (some think) hangs around this tie of year. And the August 2007 eclipse took place as the moon was setting. And again, some places around the state had clouds. Now we’ve got a February eclipse, and we all know the cloud situation at this time of the year. But one can always hope.

The eclipse this Wednesday has one thing in its favor: the timing. No already-eclipsed moon rising or setting. This one, we get to see the whole thing. The beginning partial phase of the eclipse starts just at 8.43pm, with the greatest eclipse (mid-totality) at 10.26pm. The event is over just past midnight.

At 8.43, you will begin to notice a small “bite” taken out of the edge of the moon, as the moon begins crossing into the Earth’s shadow. This darker area spreads across the surface of the moon during the next few hours, and by 10.01pm, the moon is completely immersed in shadow.

At this time the moon should have a bright, coppery orange color, as it is being lit from the sunlight that is being bent (refracted) as it passes through the Earth’s atmosphere. If it was not for this “prism” effect, the moon would be totally black, as no light would reach it.

The midpoint of totality is 10.26pm, and after that the moon slides out the other side of the shadow, with the total portion of the eclipse ending at 10.51pm and the partial eclipse ending just after midnight.

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You all know how bright the full moon is. It is the brightest thing in the night sky, drowning out the stars with its brilliance. Well, during a lunar eclipse, with the moon immersed in the Earth’s shadow, its brightness diminishes considerably, and the surrounding stars become visible for a short time. For this eclipse, the moon is near the planet Saturn in the constellation Leo, and during the darkest parts of the eclipse Saturn and the stars in the area will be prominently displayed for a short time.

And don’t be worried about looking at the eclipse. It is perfectly safe to look directly at a lunar eclipse. A solar eclipse is when you should not look directly at it. But a lunar eclipse, so ahead and let the wondrous sight fill your eyes.

With the still cold, and still snowy nights that are featured in February, the sight of an eclipsed moon hanging in the crisp, starry sky is a wondrous thing to behold. Let’s just hope it clears in time.

If you do see the eclipse, please let us know you thoughts about it.


Special Presentation: Mars Rovers

February 12, 2008

The Grand Rapids Amateur Astronomical Association is having a special event on Tuesday, February 19th. A special guest speaker will give a program on the Mars Rovers, and meteorites on the planet Mars.

Special Presentation at the Grand Rapids Public Museum’s Meijer Theater, starting at 7.30pm. Our special guest – coming in for this presentation – is James Ashley, NASA Fellow and Executive Director of Minor Planet Research, Inc. He will be speaking on “The On-going Search for Meteorites on Mars (their numbers, their significance, and their future…)”

About the Topic:

Meteorites do not just occur on Earth, but also on other bodies in the solar system. Discoveries of meteorites and meteoroid impact on the Martian surface have been made by the Mars Exploration Rovers and Thermal Imaging System (THEMIS) camera aboard the Mars Odyssey spacecraft.

Mr. Ashley will be explain the process of meteorite hunting on another world, the phenomenon of Near-Mars Objects (NMOs), what we have found, and why we care.

About the Speaker:

James Ashley is a NASA-sponsored doctoral candidate at Arizona State University’s School for Earth and Space Exploration, where he is working as a Payload Downlink Lead on the Mars Exploration Rover science team. He is also using the miniature thermal emission spectrometer (Mini-TES) instrument on both rovers to address questions relating to meteorite weathering on the martian surface. James co-founded Minor Planet Research, Inc., in 2000 to assist in addressing the impact hazard, and developed the Asteroid Discovery Station to foster interest in science and discovery among the world community of young explorers. He has given more than 1,000 public presentations on astronomical and geological topics, and served as science consultant for the History Channel program ~ Comets: Prophets of Doom.

The program begins at 8.00pm. This meeting is open to the public. All are encouraged to attend.