Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Lunar Eclipse shopping experience:
1. Compare - without doubt the biggest advantage that the Lunar Eclipse offers shoppers today is the ability to compare thousands of Lunar Eclipse at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Lunar Eclipse? Wrong! If the Lunar Eclipse is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Lunar Eclipse then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Lunar Eclipse? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Lunar Eclipse and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Lunar Eclipse wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Lunar Eclipse then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Lunar Eclipse site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Lunar Eclipse, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Lunar Eclipse, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
A
lunar eclipse occurs whenever the Moon passes through some portion of the Earth's shadow. This can occur only when the Sun,
Earth, and
Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, the Moon is always
full moon near a lunar eclipse. The type and length of an eclipse depend upon the Moon's location relative to its lunar nodes. The 28 August 2007 lunar eclipse total lunar eclipse was on 28 August 2007http://sunearth.gsfc.nasa.gov/eclipse/lunar.html where the
sun, earth and
moon were in total alignment. The initial stage started at 07:52 UTC, while the total eclipse began at 09:52 UTC giving it a bronze appearance, with reddish to blood red at its peak. Eastern
Australia and New Zealand were in the perfect zone to view the total lunar eclipse or "blood moon". Daily Telegraph, Sydney to see blood moon eclipse
Description
, an object is totally shielded from direct illumination. In contrast, within the penumbra, only a portion of the illumination is blocked.A lunar eclipse occurs at least two times a year, whenever some portion of the Earth's shadow falls upon the Moon. The Moon will always be full moon during a lunar eclipse; that is, from the perspective of the Sun, the Moon will be directly behind the Earth. However, since the Orbit of the Moon is inclined by about 5° with respect to the orbital plane of the Earth (the ecliptic), most full moons occur when the Moon is either north or south of Earth's shadow. Thus in order to be eclipsed, the Moon must be near one of the two intersection points its orbit makes with the ecliptic, which are referred to as the Moon's ascending and descending
lunar nodes.The shadow of the Earth can be divided into two distinctive parts: the
umbra and penumbra. Within the umbra, there is no direct solar radiation. However, as a result of the Sun's large angular size, solar illumination is only partially blocked in the outer portion of the Earth's shadow, which is given the name penumbra.A
penumbral eclipse occurs when the Moon passes through the Earth's
penumbra. The penumbra does not cause any noticeable darkening of the Moon's surface, though some may argue it turns a little yellow. A special type of penumbral eclipse is a
total penumbral eclipse, during which the Moon lies exclusively within the Earth's penumbra. Total penumbral eclipses are rare, and when these occur, that portion of the Moon which is closest to the umbra can appear somewhat darker than the rest of the Moon.
A
partial lunar eclipse occurs when only a portion of the Moon enters the umbra. When the Moon travels completely into the Earth's umbra, one observes a
total lunar eclipse. The Moon's speed through the shadow is about one kilometer per second (2,300 mph), and totality may last up to nearly 107 minutes. Nevertheless, the total time between the Moon's first and last contact with the shadow is much longer, and could last up to more than 6 hours. The longest calculated lunar eclipse occurring between 1000 BCE and 3000 CE took place on May 31, 318, having a duration of 1h47m14s. The relative distance of the Moon from the Earth at the time of an eclipse can affect the eclipse's duration. In particular, when the Moon is near its apogee (that is, the farthest point from the Earth in its orbit) its orbital speed is the slowest. The diameter of the umbra does not decrease much with distance. Thus, a totally-eclipsed Moon occurring near apogee will lengthen the duration of totality.
A
selenelion or
selenehelion is a type of lunar eclipse when, due to the moon's proximity to the ecliptic, both the sun and the eclipsed moon can be observed at the same time. This particular arrangement has led to the phenomenon being referred to as a
horizontal eclipse. It can only be observed just prior to sunset or just after sunrise. The specific arrangement is not common, and last occurred on May 16, 2003 over
Europe.http://www.bbc.co.uk/weather/ukweather/daily_review/news/15052003news.shtml
Appearance
grazed the northern edge of the earth's shadow, and the eclipse on
November 8 grazed the southern edge. These images show the eclipse in November was much brighter as the bottom rim of the Moon did not darken as much after completely entering the umbra. The color and brightness of the Moon during an eclipse varies according to the amount of light refracted by the Earth's atmosphere.
The Moon does not completely disappear as it passes through the umbra because of the refraction of
sunlight by the Earth's atmosphere into the shadow cone; if the Earth had no atmosphere, the Moon would be completely dark during an eclipse. The red colouring arises because sunlight reaching the Moon must pass through a long and dense layer of the Earth's atmosphere, where it is Rayleigh scattering. Shorter
wavelengths are more likely to be scattered by the small particles, and so by the time the light has passed through the atmosphere, the longer wavelengths dominate. This resulting light we perceive as
red. This is the same effect that causes sunsets and
sunrises to turn the sky a reddish colour; an alternative way of considering the problem is to realise that, as viewed from the Moon, the Sun would appear to be setting (or rising) behind the Earth.
The amount of refracted light depends on the amount of dust or clouds in the atmosphere; this also controls how much light is scattered. In general, the dustier the atmosphere, the more that other wavelengths of light will be removed (compared to red light), leaving the resulting light a deeper red colour. This causes the resulting coppery-red hue of the Moon to vary from one eclipse to the next. Volcanoes are notable for expelling large quantities of dust into the atmosphere, and a large eruption shortly before an eclipse can have a large effect on the resulting colour.
The following scale (the Danjon scale) was devised by André Danjon for rating the overall darkness of lunar eclipses:
L=0: Very dark eclipse. Moon almost invisible, especially at mid-totality.
L=1: Dark Eclipse, gray or brownish in colouration. Details distinguishable only with difficulty.
L=2: Deep red or rust-colored eclipse. Very dark central shadow, while outer edge of umbra is relatively bright.
L=3: Brick-red eclipse. Umbral shadow usually has a bright or yellow rim.
L=4: Very bright copper-red or orange eclipse. Umbral shadow has a bluish, very bright rim.
, England.
Eclipse cycles
Every year there are at least two lunar eclipses. If one knows the date and time of an eclipse, it is possible to predict the occurrence of other eclipses using an
eclipse cycle like the Saros cycle. Unlike a solar eclipse, which can only be viewed at a certain relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of the Earth.
See also
Gallery
Image:Lunar2007 eclipse-LiamG.jpg|March 2007. The advancing shadow of Earth brings out detail on the lunar surface. The huge ray system emanating from Tycho (crater) is shown as the dominant feature on the southern hemisphere.Image:Lunar eclipse with stars.JPG|August 2007. A total lunar eclipse allows more
stars to be seen near the moon.Image:Total lunar eclipse and milky way.jpg].Image:August_2007_Lunar_Eclipse.jpg|August 28, 2007 lunar eclipse, a collage of photos taken from the Oregon coast by Randall Scholten.Image:2007-08-28 Melbourne lunar eclipse Dsc 2519.jpg|Total lunar eclipse taken from Melbourne, Australia on August 28, 2007Image:Total lunar eclipse august 28 2007 edit.jpg|A sequence of images taken at 3 minute intervals showing the 28 August 2007 lunar eclipseImage:Lunar-eclipse-2004.jpg|Multiple exposure composite photo of the lunar eclipse of October 2004 as seen from Northern California.
References
External links
- U.S. Navy Lunar Eclipse Computer
- NASA Eclipse home page
- Lunar Eclipses for Beginners
- Shadow and Substance for animation of future and past eclipses
A
lunar eclipse occurs whenever the
Moon passes through some portion of the Earth's shadow. This can occur only when the
Sun, Earth, and
Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, the Moon is always
full moon near a lunar eclipse. The type and length of an eclipse depend upon the Moon's location relative to its lunar nodes. The
28 August 2007 lunar eclipse total lunar eclipse was on
28 August 2007http://sunearth.gsfc.nasa.gov/eclipse/lunar.html where the sun, earth and moon were in total alignment. The initial stage started at 07:52 UTC, while the total eclipse began at 09:52 UTC giving it a bronze appearance, with reddish to blood red at its peak. Eastern
Australia and New Zealand were in the perfect zone to view the total lunar eclipse or "blood moon". Daily Telegraph, Sydney to see blood moon eclipse
Description
, an object is totally shielded from direct illumination. In contrast, within the penumbra, only a portion of the illumination is blocked.A lunar eclipse occurs at least two times a year, whenever some portion of the Earth's shadow falls upon the Moon. The Moon will always be
full moon during a lunar eclipse; that is, from the perspective of the Sun, the Moon will be directly behind the Earth. However, since the
Orbit of the Moon is inclined by about 5° with respect to the orbital plane of the Earth (the
ecliptic), most full moons occur when the Moon is either north or south of Earth's shadow. Thus in order to be eclipsed, the Moon must be near one of the two intersection points its orbit makes with the ecliptic, which are referred to as the Moon's ascending and descending
lunar nodes.The shadow of the Earth can be divided into two distinctive parts: the
umbra and
penumbra. Within the umbra, there is no direct solar radiation. However, as a result of the Sun's large angular size, solar illumination is only partially blocked in the outer portion of the Earth's shadow, which is given the name penumbra.A
penumbral eclipse occurs when the Moon passes through the Earth's
penumbra. The penumbra does not cause any noticeable darkening of the Moon's surface, though some may argue it turns a little yellow. A special type of penumbral eclipse is a
total penumbral eclipse, during which the Moon lies exclusively within the Earth's penumbra. Total penumbral eclipses are rare, and when these occur, that portion of the Moon which is closest to the umbra can appear somewhat darker than the rest of the Moon.
A
partial lunar eclipse occurs when only a portion of the Moon enters the umbra. When the Moon travels completely into the Earth's umbra, one observes a
total lunar eclipse. The Moon's speed through the shadow is about one kilometer per second (2,300 mph), and totality may last up to nearly 107 minutes. Nevertheless, the total time between the Moon's first and last contact with the shadow is much longer, and could last up to more than 6 hours. The longest calculated lunar eclipse occurring between 1000 BCE and 3000 CE took place on
May 31,
318, having a duration of 1h47m14s. The relative distance of the Moon from the Earth at the time of an eclipse can affect the eclipse's duration. In particular, when the Moon is near its apogee (that is, the farthest point from the Earth in its orbit) its orbital speed is the slowest. The diameter of the umbra does not decrease much with distance. Thus, a totally-eclipsed Moon occurring near apogee will lengthen the duration of totality.
A
selenelion or
selenehelion is a type of lunar eclipse when, due to the moon's proximity to the ecliptic, both the sun and the eclipsed moon can be observed at the same time. This particular arrangement has led to the phenomenon being referred to as a
horizontal eclipse. It can only be observed just prior to sunset or just after sunrise. The specific arrangement is not common, and last occurred on May 16,
2003 over
Europe.http://www.bbc.co.uk/weather/ukweather/daily_review/news/15052003news.shtml
Appearance
grazed the northern edge of the earth's shadow, and the eclipse on
November 8 grazed the southern edge. These images show the eclipse in November was much brighter as the bottom rim of the Moon did not darken as much after completely entering the umbra. The color and brightness of the Moon during an eclipse varies according to the amount of light refracted by the Earth's atmosphere.
The Moon does not completely disappear as it passes through the umbra because of the
refraction of sunlight by the Earth's atmosphere into the shadow cone; if the Earth had no atmosphere, the Moon would be completely dark during an eclipse. The red colouring arises because sunlight reaching the Moon must pass through a long and dense layer of the Earth's atmosphere, where it is
Rayleigh scattering. Shorter
wavelengths are more likely to be scattered by the small particles, and so by the time the light has passed through the atmosphere, the longer wavelengths dominate. This resulting light we perceive as red. This is the same effect that causes sunsets and sunrises to turn the sky a reddish colour; an alternative way of considering the problem is to realise that, as viewed from the Moon, the Sun would appear to be setting (or rising) behind the Earth.
The amount of refracted light depends on the amount of dust or clouds in the atmosphere; this also controls how much light is scattered. In general, the dustier the atmosphere, the more that other wavelengths of light will be removed (compared to red light), leaving the resulting light a deeper red colour. This causes the resulting coppery-red hue of the Moon to vary from one eclipse to the next. Volcanoes are notable for expelling large quantities of dust into the atmosphere, and a large eruption shortly before an eclipse can have a large effect on the resulting colour.
The following scale (the
Danjon scale) was devised by
André Danjon for rating the overall darkness of lunar eclipses:
L=0: Very dark eclipse. Moon almost invisible, especially at mid-totality.
L=1: Dark Eclipse, gray or brownish in colouration. Details distinguishable only with difficulty.
L=2: Deep red or rust-colored eclipse. Very dark central shadow, while outer edge of umbra is relatively bright.
L=3: Brick-red eclipse. Umbral shadow usually has a bright or yellow rim.
L=4: Very bright copper-red or orange eclipse. Umbral shadow has a bluish, very bright rim.
,
England.
Eclipse cycles
Every year there are at least two lunar eclipses. If one knows the date and time of an eclipse, it is possible to predict the occurrence of other eclipses using an eclipse cycle like the Saros cycle. Unlike a
solar eclipse, which can only be viewed at a certain relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of the Earth.
See also
Gallery
Image:Lunar2007 eclipse-LiamG.jpg|March 2007. The advancing shadow of Earth brings out detail on the lunar surface. The huge ray system emanating from
Tycho (crater) is shown as the dominant feature on the southern hemisphere.Image:Lunar eclipse with stars.JPG|August 2007. A total lunar eclipse allows more
stars to be seen near the moon.Image:Total lunar eclipse and milky way.jpg].Image:August_2007_Lunar_Eclipse.jpg|August 28, 2007 lunar eclipse, a collage of photos taken from the Oregon coast by Randall Scholten.Image:2007-08-28 Melbourne lunar eclipse Dsc 2519.jpg|Total lunar eclipse taken from Melbourne, Australia on August 28, 2007Image:Total lunar eclipse august 28 2007 edit.jpg|A sequence of images taken at 3 minute intervals showing the 28 August 2007 lunar eclipseImage:Lunar-eclipse-2004.jpg|Multiple exposure composite photo of the lunar eclipse of October 2004 as seen from Northern California.
References
External links
- U.S. Navy Lunar Eclipse Computer
- NASA Eclipse home page
- Lunar Eclipses for Beginners
- Shadow and Substance for animation of future and past eclipses
BBC NEWS | Science/Nature | Lunar eclipse wows sky watchers
People across the world watch the moon turn red as the first lunar eclipse in more than three years takes place.
Lunar Eclipse - Official Site
Official Homepage of Lunar Eclipse
Partial Eclipse of the Moon: 2008 August 16
Partial Eclipse of the Moon, 2008 August 16 ... Partial Eclipse of the Moon: 2008 August 16 Global Circumstances. The global visibility of this lunar eclipse is shown in the ...
HMNAO Eclipse Portal
eclipse, solar, lunar ... Explanatory Material Lunar Eclipse diagrams. Information on lunar eclipses is presented in the form of a diagram consisting of two parts.
BBC - Science & Nature - Space - Lunar Eclipse
Find out about lunar eclipses in BBCi's guide to the Moon. ... LUNAR ECLIPSES. A lunar eclipse occurs when the Earth passes between the Moon and the Sun.
Lunar eclipse - Wikipedia, the free encyclopedia
A lunar eclipse occurs whenever the Moon passes through some portion of the Earth's shadow. This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely ...
Lunar Eclipse
What is the Lunar Eclipse project ? It is a collection of plugins I wrote to make my work with eclipse easier. Stefan has joined me to create the Editor Enhancements plugin.
Newbury Today | West Berks sees lunar eclipse
Astronomers and photgraphers out in force for the event - view your snaps here ... Astronomers and photgraphers out in force for the event - view your snaps here
Lunar Eclipse
Flashlets Home Page
NASA - Get Ready For February's Total Lunar Eclipse
View lunar eclipse preview video Credit: NASA In the late night hours of Feb. 20, 2008, a total lunar eclipse will dazzle the night sky. And this lunar eclipse may be worth staying ...
