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Looking for a holiday in the sun? How about sunshine for 24 hours a day for up to 6 straight months of the year?

The natural phenomenon where the sun doesn’t dip below the horizon at local midnight meaning 24-hours of daylight is called “The midnight Sun”.

Northern and Southern hemispheres each tilt toward and away from the Sun during their respective summers and winters much more than areas aro und the equator where the angle remains much closer to perpendicular and more constant. Therefore larger seasonal variations are found the further you go away from the equator and closer towards each of the poles.

During the summer solstices in the Northern Arctic Circle and the Southern Antarctic Circle the tilt of each hemisphere’s polar circle is angled towards the Sun and remains so throughout the 24-hour period it takes to complete a single rotation of the Earth. This means that a person who is standing within a polar circle at summer solstice of the respective hemisphere would not see the Sun dip below the horizon, it would appear to dip nearer the horizon as it approached midnight local time and then begin to rise again once local midnight had passed.

The number of days per year that mi dnight Sun will occur will increase the further one goes into the polar circles and towards the respective pole. Taking the Arctic circle as an example the Northern most inhabited Island of Svalbard, Norway experiences no sunset and constant daylight from 19th April to 23rd August each year. The North Pole itself has only one sunrise and one sunset a year and spends 6 straight months in daylight.

The opposite natural phenomenon that occurs during winter months is known as “Polar night” and occurs in the same way with up to 6 straight months of no Sun and darkness at each pole.

-Matt J

Photo shows a time lapse as the time approaches local midnight and after it:  @http://www.placesmustseen.com/?p=302

 Solar Analemma

No. The image does not depict UFOs.

<span style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Its actually Solar Analemma!

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">“What’s a Solar Analemma?”

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">I am so glad you asked!

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Photograph the position of the Sun in the sky every day, at the same time (for example 2pm) from the same place (for example a hilltop on Earth). If you do this for one complete year, you will have 365 positions recorded. If you superimpose these positions onto one image, you will notice a pattern. An obscure figure 8. This pattern is referred to as a Solar Analemma!

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">The reason for this pattern can be attributed to the fact that the orbital path of Earth around the Sun is elliptical and that the Earth is tilted on its axis with respect to its orbit (or its plane of orbit).

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">The size and shape of the analemma is influenced by three variables:

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">1. Axial tilt <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">2. Orbital Eccentricity <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">3. Angle between the apse line (imaginary line defined by the orbit's eccentricity vector) and the line of solstices

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Due to the aforementioned variables, different planets have different analemmas. Mars, for example, has a tear drop shaped analemma. This shape is attributed to the fact that the orbital eccentricity of Mars “outweighs” the tilt of its axis. Venus, Jupiter, Saturn, Uranus, Neptune and dwarf planet Pluto all have an analemma in the general shape of a figure 8.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Mercury’s analemma (an approximate straight line) is determined by calculating the equation of time. This method is used as a single day on Mercury last two years. Therefore, plotting the position of the Sun each day at the same time will result in unusable data. Venus faces a similar problem as a single year lasts almost two days.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">If a planet had a circular orbit with no axial tilt the Sun would be in the same position, at the same time, everyday for the whole year. The resulting analemma would be a single point.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Dennis di Cicco was the first person to create an analemma photograph. He did this in 1978-1979 in New England, USA. Using a solar filter he made 44 exposures on a single frame.

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">You may remember that in the movie “Cast Away”, the main character (portrayed by Tom Hanks) etched an analemma in stone to keep track of the date. <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">♞Renesh T

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Further reading & image source:

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Image Credit: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">Astrosurf <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">• http://webodysseum.com/technologyscience/analemma-location-of-the-sun-each-day-at-the-same-time/

<span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">References: <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">• www.analemma.com/ <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">• http://scienceblogs.com/startswithabang/2009/08/26/why-our-analemma-looks-like-a/ <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">• @http://www.universetoday.com/50303/analemma <span class="text_exposed_show" style="background-color: #ffffff; color: #333333; font-family: 'lucida grande',tahoma,verdana,arial,sans-serif; font-size: 12.800000190734863px;">• @http://www.mtgrafix.com/programs/analemma/planets.html

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