We had a lunar eclipse on July 7 and there's a solar eclipse on July 21. The lunar eclipse was only visible from the western U.S. and points further west into the Pacific, but the next one on August 5-6 will be visible on the east coast, as well (in the evening just after sunset). The solar eclipse will be visible in China but not in the western hemisphere.
A lunar eclipse occurs when the earth is directly between the sun and the moon, thus blocking any direct solar radiation. This leaves the moon illuminated only by "earthlight", which makes it glow an eery red. This is because the bouncing back and forth through atmosphere causes the shorter, bluer wavelengths to be absorbed, leaving the longer red wavelengths.
A solar eclipse occurs when the moon is directly between the sun and the earth. Since the moon's orbit is not right on the ecliptic plane (the plane on which the earth revolves around the sun), this doesn't happen every month. You can guess the time of an eclipse (lunar or solar), however, by looking at a calendar that has both the date and the time of the full and new moons. A lunar eclipse only occurs during a full moon and a solar eclipse only occurs during a new moon because those are the only times when the moon crossing the ecliptic plane coincides with the earth or moon blocking the sun.
There are many solar and lunar eclipse calculators online. NASA has a good one:
Solar Eclipse: http://eclipse.gsfc.nasa.gov/JSEX/JSEX-index.html
And this one comes from the Naval Oceanography Portal:
Lunar Eclipse: http://www.usno.navy.mil/USNO/astronomical-applications/data-services/lunar-ecl-us
As a rule, partial eclipses are more common than total eclipses and lunar eclipses are more common than solar eclipses. I've seen several total lunar eclipses, but only two partial solar eclipses (I would have seen a third one when I was a kid, but heavy cloud cover hid it).
In addition to total and partial lunar eclipses, there are also "penumbral" eclipses, in which the moon darkens a little from the earth's shadow but not much as in a partial/total eclipse. Both this month and next month's eclipses are penumbral.
Thursday, July 9, 2009
Thursday, July 2, 2009
Mars and Venus and Jupiter oh my!
—I set the alarm for 03:30 this morning to do some sky watching at a different time. One of my first goals, early in my astronomical career, is to view all the other 7 planets as soon as possible. With only Saturn under my belt, there was much to accomplish!
—So the alarm went off and like any normal work morning, I drug my butt into the bathroom and splashed water on my face. Then I put in my contacts, donned my shoes, and went out for an early morning stroll to my viewing area. To my delight, not only was Jupiter shining down from high above, but both Venus and Mars were up in the East! So off to the house I ran to grab my scope and case.
—There were some seriously disturbing sounds coming from further down the hill from my observation area that I have yet to determine what they were. It sounded like the noise upset squirrels make, on an amp, and echoing. AND there were two of them talking to one another. Fortunately for all involved, the noises did not come closer and I was left happily alone.
—Note on the weather. It was in the lower 60’s, low humidity (YAY!) and a slight breeze. It was cool enough, I put on a long sleeve shirt.
—Scope set up, lens cap off and eye piece in, what to look at first? I go with Jupiter which is high in the sky. Jupiter was spectacular through my 26 mm EP, seems like I could see two moons? Curious as I am I can’t linger and so I then point the scope over to the Eastern horizon and gander at Mars, which proves to be a disappointment overall. Then down a little a little to Venus which a: was plainly visible to me standing up, but was hiding amongst the tops of the 6 foot tall grass in my field, and B: had a huge diffraction spike. GGrrrr. I could see enough to tell there was a little more than half of it visible.
—So out with the 26mm and in with the 6mm and back to Jupiter. This time I could distinctly see two bands on Jupiter. I hovered over it quite a bit trying to fine tune the focuser (Which I have determined I hate). Truly a grand site Jupiter is!
—Then back to Mars which again even in the 6mm EP was nothing more than a tiny orange-ish disk. Wondering to myself if I will be able to make it bigger with a 12″ scope? Or is it because Mars is so far away right now? So many questions.
—Then back to Venus! The diffraction spikes were even worse in the 6mm EP, but at least it had cleared the grass and it was a sharp spiky object lol. I’d like to see it high in the sky. Unsure how long it will be until it is higher again.
—After Venus through the 6mm EP I wanted another peep at Jupiter. To my dismay it was now behind the tip top of a tree to the South even though I could see it clearly standing up. Dang it anyway! So now I know that the first concrete pad I poured is a bit to close to the tree to the South. Going to have to pour another pad soon…
—I then pulled out the 17mm EP and took a look at a blurry spot just to the east of Mars. Turned out to be a spectacular open star cluster. Anyone know what one I was looking at right before sunrise? While staring at that heavenly body, Sol decided to start peeping above the horizon. My my 90 mins went by fast! Then I noticed that Mercury had risen! Could I have first light on 4 planets in the same night? Nope, no way. It was way down in the grass, and I couldn’t begin to get to it with the scope. Going to go weed that grass today, wish me luck…
—I decided then to pack it up and head back to bed. I got first light on three planets and one star cluster. All in all a very productive 90 mins in the wee hours of the morning!
—Things I learned
1: I need my lap top there with me so I can have Stellarium at my finger tips. This is going to require a portable power supply or 200 feet of extention cords…
2: My focuser is awful. Anyone suggest a good 1.25 focuser?
3: To much tall grass around my viewing area. Can you say weedeater?
—So the alarm went off and like any normal work morning, I drug my butt into the bathroom and splashed water on my face. Then I put in my contacts, donned my shoes, and went out for an early morning stroll to my viewing area. To my delight, not only was Jupiter shining down from high above, but both Venus and Mars were up in the East! So off to the house I ran to grab my scope and case.
—There were some seriously disturbing sounds coming from further down the hill from my observation area that I have yet to determine what they were. It sounded like the noise upset squirrels make, on an amp, and echoing. AND there were two of them talking to one another. Fortunately for all involved, the noises did not come closer and I was left happily alone.
—Note on the weather. It was in the lower 60’s, low humidity (YAY!) and a slight breeze. It was cool enough, I put on a long sleeve shirt.
—Scope set up, lens cap off and eye piece in, what to look at first? I go with Jupiter which is high in the sky. Jupiter was spectacular through my 26 mm EP, seems like I could see two moons? Curious as I am I can’t linger and so I then point the scope over to the Eastern horizon and gander at Mars, which proves to be a disappointment overall. Then down a little a little to Venus which a: was plainly visible to me standing up, but was hiding amongst the tops of the 6 foot tall grass in my field, and B: had a huge diffraction spike. GGrrrr. I could see enough to tell there was a little more than half of it visible.
—So out with the 26mm and in with the 6mm and back to Jupiter. This time I could distinctly see two bands on Jupiter. I hovered over it quite a bit trying to fine tune the focuser (Which I have determined I hate). Truly a grand site Jupiter is!
—Then back to Mars which again even in the 6mm EP was nothing more than a tiny orange-ish disk. Wondering to myself if I will be able to make it bigger with a 12″ scope? Or is it because Mars is so far away right now? So many questions.
—Then back to Venus! The diffraction spikes were even worse in the 6mm EP, but at least it had cleared the grass and it was a sharp spiky object lol. I’d like to see it high in the sky. Unsure how long it will be until it is higher again.
—After Venus through the 6mm EP I wanted another peep at Jupiter. To my dismay it was now behind the tip top of a tree to the South even though I could see it clearly standing up. Dang it anyway! So now I know that the first concrete pad I poured is a bit to close to the tree to the South. Going to have to pour another pad soon…
—I then pulled out the 17mm EP and took a look at a blurry spot just to the east of Mars. Turned out to be a spectacular open star cluster. Anyone know what one I was looking at right before sunrise? While staring at that heavenly body, Sol decided to start peeping above the horizon. My my 90 mins went by fast! Then I noticed that Mercury had risen! Could I have first light on 4 planets in the same night? Nope, no way. It was way down in the grass, and I couldn’t begin to get to it with the scope. Going to go weed that grass today, wish me luck…
—I decided then to pack it up and head back to bed. I got first light on three planets and one star cluster. All in all a very productive 90 mins in the wee hours of the morning!
—Things I learned
1: I need my lap top there with me so I can have Stellarium at my finger tips. This is going to require a portable power supply or 200 feet of extention cords…
2: My focuser is awful. Anyone suggest a good 1.25 focuser?
3: To much tall grass around my viewing area. Can you say weedeater?
Thursday, June 25, 2009
Chasing the New Moon
For about six months now, I've been trying to catch the first day that you can see the crescent moon in the first quarter of its cycle. I never seem able to get closer than the second day. Have caught the second day before the New Moon, maybe even the last day, but not right afterward.
Monday was the New Moon and I tried to catch it yesterday. But despite a half-clear sky, what clouds there were seemed to congregate over the setting sun (I suspect there's an actual metereological reason for this involving the concentration of solar heat in the west at that time of day, but haven't worked out what just yet). So, I didn't see it until tonight, when it was a bit more than a sliver.
Due to the usage of the lunar cycles in many religious calendars, astronomical observation is actually a critical matter of good religious observance. Yes, for all of the denigration of religion in some quarters as antiscience, religious calendars are in fact heavily based on science, especially astronomy.
For example, there was considerable dispute over when to start Ramadan among Muslims until easy and quick reporting from Mecca became available. It doesn't seem like much to non-Muslims, but for Muslims, Ramadan is a holy month. If you start and end it too early, you're doing the wrong thing. If you don't start it once the moon reappears in the sky, you're doing the wrong thing. Think of it as if Christmas were based on the lunar calendar: you would want to know the exact date, but the date would be partially dependent on good astronomical observation--and weather.
Passover and Easter are also regulated by a lunar calendar--or, they were originally. Because they are so strongly connected to the spring (i.e. a solar/seasonal calendar), the lunar part of their calculation is restricted to a period in spring of about two months. This is why both float around the spring months of the calendar each year. And because the Christian aspect of Easter was originally a Passover festival, the two festivals not-infrequently fall on the same date.
Monday was the New Moon and I tried to catch it yesterday. But despite a half-clear sky, what clouds there were seemed to congregate over the setting sun (I suspect there's an actual metereological reason for this involving the concentration of solar heat in the west at that time of day, but haven't worked out what just yet). So, I didn't see it until tonight, when it was a bit more than a sliver.
Due to the usage of the lunar cycles in many religious calendars, astronomical observation is actually a critical matter of good religious observance. Yes, for all of the denigration of religion in some quarters as antiscience, religious calendars are in fact heavily based on science, especially astronomy.
For example, there was considerable dispute over when to start Ramadan among Muslims until easy and quick reporting from Mecca became available. It doesn't seem like much to non-Muslims, but for Muslims, Ramadan is a holy month. If you start and end it too early, you're doing the wrong thing. If you don't start it once the moon reappears in the sky, you're doing the wrong thing. Think of it as if Christmas were based on the lunar calendar: you would want to know the exact date, but the date would be partially dependent on good astronomical observation--and weather.
Passover and Easter are also regulated by a lunar calendar--or, they were originally. Because they are so strongly connected to the spring (i.e. a solar/seasonal calendar), the lunar part of their calculation is restricted to a period in spring of about two months. This is why both float around the spring months of the calendar each year. And because the Christian aspect of Easter was originally a Passover festival, the two festivals not-infrequently fall on the same date.
Saturday, June 20, 2009
First Light!
As my wife described it, I was like a kid in a candy store. I had everything set out early and waited patiently (or maybe not so) for the sun to set. With each passing minute I scanned the sky for the first twinkling star. Up and down the hill I went while helping the wife cook on the grill.
—Finally there it was… Vega! Down the hill I ran and uncapped the scope. Turned on the view finder, centered the dot and presto, there was nothing there. Instantly I worried about my collimation, was it any good? Would this be a fruitless evening trying to achieve first light? In and out I turned the focuser and presto, there was a star. Very faint it was, and not Vega at all, but a sharp, well focused star.
—So up the hill I went to get the wife and tell her my collimation was successful! All I had to do now was adjust my view finder so I could start scanning the heavens. Sadly there were no planets to view or moon to use as a focus point. I had to hope that I could match the star in my view finder and the one in my eye piece. For the next two hours I struggled with it, and guess what? No success at all. I decided to focus on the Mizar/Alcor double star in Ursa Major. I could put the red dot right on it, but never find it in the scope.
—So ‘First Light’ was a mixture of highs and lows. punctuated by another upset buck white tail dear and my two labs that wouldn’t get out from underfoot. I did mix in some yummy burgers on the grill in the middle of it all. Not to mention I did see the HIP 91919A/91926C Binary system, which was really cool.
—All in all a successful evening I hope to do again next week. I hope you enjoyed my account and would love some feedback on how everyone is enjoying my blogs..
Friday, June 19, 2009
KAGUYA's last pictures
Just before her impact on the Moon surface, the Japanese Lunar Probe, KAGUYA, sent the final pictures taken with her High Definition camera. Las picture in the sequence was taken 1 minute before impact.
Wednesday, June 17, 2009
Tuesday, June 16, 2009
Astrocation 2009
Have you ever wanted to know what it is like to be at some of the biggest and coolest observatories in the world? Well now you can, starting today! I will be touring New Mexico, Arizona, and California looking for all places/things astronomy related. I will be giving full coverage via, video, blog, pictures, and Twitter. So here is how you can follow along:
Twitter: for the fast and up to date observing, traveling and random experiences.
Flickr: Be the first to see all of my astrocation photos, be it astrophotography or just some observatory shots I will post all of them here. (Videos too!)
My Blog: Long stories, interviews and experiences will be posted!
So tune in and dont be shy submit questions, comments, and tell me what to observe/Image! Untill then!
Elias Jordan
You are not the Center of the Universe
Thanks to Edwin Hubble on the XX Century, we have learned that our place in the Universe is not as priviledged as we used to think.
Monday, June 15, 2009
Tips for Those Wearing Glasses
Observing from the City
Baby Stars Finally Found In Jumbled Galactic Center
Astronomers have at last uncovered newborn stars at the frenzied center of our Milky Way galaxy. The discovery was made using the infrared vision of NASA's Spitzer Space
full story
full story
Saturday, June 13, 2009
Welcome to are new Blog Authors
lEurekaAstronomy
UngaMan
Elias_Jordan
Paula R. Stiles
Gene J. Mikulka
Welcome AllThank You
Subscribe to:
Posts (Atom)
Posts
