Make your own free website on Tripod.com
September 2000 Issue

Astronomy Digest

Support "Astronomy Digest" by visiting our sponsor. It only takes a click.






Email

Link
to us



Bookstore

Books

Books2

Software

Front Desk

News Throughout
the Net

Updated Weekly


A Star is Born - Hubble Space Telescope is there. - MSNBC, September 7, 2000.


New Type of Meteorite Found - It has a new chemical composition. - CNN, September 6, 2000.


Solar Maximum is in Full Swing - Part of the eleven year cycle. - SSN, September 5, 2000.


Asteroid Fly-by - Asteroid passed by the Earth only 12 times farther from our planet than the Moon. - SSN, September 1, 2000.


Old Galaxies - New evidence shows Red Shift Higer which means galaxies may be older than once thought. - BBC, August 18, 2000.


Moon Meteorite - Moon rock found on earth. - MSNBC, August 18, 2000.


Linear Breakup - Hubble images record the event. - CNN, August 10, 2000.


National Security Agency Files Released - UFO hunters hope to find evidence of ET. - CNN, August 8, 2000.


Save Pluto - Congress may cut budget. - CNN, July 29, 2000.


2004 Mission to Mars - NASA unveils plans. - ABC, July 28, 2000.


Parts Break Off Comet - Hubble Space Telescope took pictures of Comet LINEAR. - ABC, July 28, 2000.


Supernovae Spreads Key Elements of Life - Chandra X-ray Observatory shows details. - SSN, July 18, 2000.


Comet Linear - Update on path of a comet you can see with binoculars. - BBC, July 17, 2000.


New Type of Solar Flare - NASA's Chandra X-ray Observatory discovered a solar flare that is not a brown dwarf, or failed star. - SSN, July 12, 2000.




September Skies


September 05 - First Quarter
September 13 - Full Moon
September 21 - Last Quarter
September 27 - New Moon


Skywatching Center - Current Month's Skies.

Astronomy Magazine - This Month's Sky Show.

Sky & Telescope - September 2000 Skies.




HandTech.com


Multiple Star Systems
By Stuart Lolly






More than sixty five percent of the stars you see in the sky are multiple stars. That is, you are looking at two or more stars. Stars that orbit each other and are bound by gravity are called multiple star systems. There are also optical multiples. This is where two or more stars appear to be close to each other. However, when you measure the distance of the stars, the stars are very far apart. There is no gravitational relation.

Our solar system orbits only one star. Solar systems with only one star are called, "Single Star Systems". Scientist feel that we were very close to being a multiple star system. Jupiter is a very large gasses planet. It is over 11 times the diameter of earth. If it would have become twice its current size, it may have become a star.

Amateur Astronomers try to split stars. They focus their telescope on what appears to be a single star. Then, change lenses and increase power until two stars are revealed.

Albireo is one of the most beautiful double stars in the sky. In the constellation Cygnus, meaning swan, Albireo is the star in the bill of the swan. Use your telescope at a low power and find Albireo. Increase the power by changing lenses. You will find that Albireo is actually made up of two stars. One of the stars will be blue, and the other yellow. The two stars bright contrast in colors make for a great example of multiple stars.


Photographs by Naoyuki Kurita, publisher of Stellar Scenes . Stop by his web site for other great astrophotographs. His work is copyrighted, so please do not copy them without his permission.

The Philosopher Pharaoh and the Total Solar Eclipse
by
Aymen M Ibrahem

Atenism, the cult of the Aten (the Sun's disk), received a powerful boost when it was adopted by Pharaoh Amenhotep IV (1352-1335 BC). The fervent Atenist changed his name to Akhenaten (the Servant of the Aten). The Philosopher Pharaoh even displaced the capital of the Egyptian Empire from Thebes to Akhetaten 'Horizon of the Aten', a city he built on the eastern bank of the Nile, in the middle between Thebes and the old, northern capital Memphis.

The reason behind the king's choice of the location of the city has not been disclosed, apart from the king's declaration that it was the Aten alone who guided him to this spot.

An Egyptologist believes that the site of the city was chosen for the geographic features that surrounds it: the uniform band of distant cliffs become interrupted by a prominent gap (the Royal Wadi) in the center of the encircling hills, forming a gigantic representation of the hieroglyph Akhet 'horizon', when the Sun rises. He believs that this may have been the sign the king was searching, and may have suggested the name 'Akhetaten'.

I agree with the above proposal, but I am not totally convinced . . . No other major city in ancient Egypt such as Thebes, Memphis, or Helioplois shows the same geographic features. And, there could be many such places along the Nile Valley.

I have speculated that the sign the young pharaoh was searching was in the heaven, rather than on the Earth . . . A total solar eclipse could have been a most spectacular sign . . .

Using an eclipse-prediction software, I scanned all the eclipses that were visible in Egypt during the reign of Pharaoh Amenhotep III (1390-1352 BC), and his son and successor Akhenaten. I found that a total solar eclipse was visible in Egypt on August 15, 1352 BC. The totality path crossed the middle of the Egyptian Nile, quite close to the site of Akhetaten (27 deg 35 min N, 30deg, 55 min E), yet that location did not enjoy a total eclipse. However, when I applied the coordinates of the city of Akhetaten to the software, the view of the eclipsed Sun at maximum eclipse was quite meaningful: a very deep partial solar eclipse (magnitude 0.997), with only a slight crescent of sunlight managed to remain visible.

The sunlight cast from behind the dark New Moon must have looked much like the representation of the Aten (a red raying sun disc), the sign the king had been searching for, I believe.

There is more evidence supporting this postulate. The city was dominated by a magnificent temple dedicated to the Aten. The temple contained a smaller, closed structure called Gem-Aten 'Aten is Found', a clear indication that the king was seeking a heavenly sign, since the Aten (the Sun disc), exists in the sky! The 'Hymn of the Aten' clearly depicts the eclipse.

I think we have just solved a 3,351 years old enigma: the peculiarity of the site of Akhetaten, and probably even the reason behind the displacement of the capital of the Egyptian Empire from Thebes to Akhetaten. The ancient Egyptian total solar eclipse of 1352 BC was indeed an eclipse that changed the history of the ancient Middle East!

An Astronomical Approach to the Puzzle of Co-Regency

There has been a controversy over a co-regency period between Akhenaten and his father, with strong arguments both for and against. For example, some text books give a co-regency period of about 7 or 8 years starting in 1356 BC. If so, Akhenaten's Year 4 (fourth regnal year) must have been 1352 BC.

The king decided to build the city in his Year 4, after a visit to the location of the city in Year 4 . . . Further, the king celebrated a royal jubilee, again, in Year 4. In ancient Egypt, the royal jubilee was celebrated traditionally in Year 30 of a king's reign. I find the total solar eclipse a very plausible reason behind this untradional, too early date of the jubilee.

The few facts mentioned above, show clearly that Year 4 was 1352 BC either in a sole rule or a co-regency. However, most chronologies agree that Amenhotep III reigned at least untill 1352 BC. Also, the author has shown that Year 9 of Amenhotep I was absolutely 1517 BC (Ibrahem 2000), implying that the co-regency period actually started in 1356 BC. (Refer to the author's paper 'The Dream that Has Come True').

Akhetaten

The name of the city as we mentioned earlier is Akhetaten, usually translated as 'The Horizon of Aten'. However it seems clear now that the name of the city means 'The Eclipse of Aten', since in a solar eclipse, the Sun seems to pass through a horizon in the sky behind which it disappears then reappears with a brief night of a few minutes in between (totality). The horizon of the Aten is clearly a horizon in the sky, a total eclipse of the Sun (the author has shown that the ancient Egyptians described eclipses as the 'Horizon of Heaven' or the 'Horizon of God'). It also seems clear that the name of the Great Pyramid, the tomb of King Khufu, should be translated as 'The Eclipse of Khufu', not the 'Horizon of Khufu', since a solar eclipse represents a heavenly grave of the Sun.

Aymen Ibrahem

Copy rights: Aymen Ibrahem, 2000.


Aymen Mohamed Ibrahem is a young professional astronomer from Egypt, graduated in 1995. His research work is mainly on comets and archaeo-astronomy and is also a very dedicated observational astronomer, and has a good reflector telescope. Aymen can be contacted at: aymoib@frcu.eun.eg .



Astrophotography
– How to get started.

By Todd Carlson

If you're like me, you probably at least a few times have looked at a spectacular astrophoto either online, in a magazine or book and wished you could take a picture just like it. Eventually I decided I wanted to be able to take astrophotos myself. There were only a few small problems. I had absolutely no clue how to use a camera other than the simple point-and-shoot type camera. Even with that type of camera I usually got a good shot of my thumb! The other problem was that I didn't have thousands of dollars to invest in an expensive mount to track the sky. After doing some investigating, I found that all I needed to take good astrophotos were a camera on a tripod and a little bit of practice. That's all you need too.

A lot of people already have a camera. The best types of cameras to use for on-tripod astrophotography are cameras that have interchangeable lenses, called SLR (single lens reflex) cameras. Cameras that don't have any batteries, such as the Olympus OM-1 or the Pentax K1000 are preferred by most veteran astrophotographers. The reason is simple---batteries can drain quickly if the shutter is being held open for an extended period of time. Neither of these two cameras is made any longer, but can be found quite easily in stores that sell used equipment. If the camera you have needs batteries, ensure that the shutter can be held open for at least 30 seconds at a time. Don't forget to keep some extra batteries on hand! As well, if your camera is a zoom-type camera where you cannot change lenses, don't worry, it can still be used.

A good, sturdy tripod is also required. The more sturdy the better. A small tripod will have a tendency to vibrate in the smallest gust of wind or will shake when the shutter is tripped. I use a video camera tripod that works quite well.

A cable release to enable the shutter to be tripped is also required. Without this your finger will vibrate the camera as you press the button. If the camera you have is a battery operated camera where you can set the exposure time, this item is not needed.

Depending on what you plan on shooting, different subjects require different film. Basic shots of constellations or auroras need fast film. Fast film is film that has a high numerical rating (such as 800 or 1000) and absorbs light quickly. You do not want to use the everyday film you would use to photograph pets, friends, etc. The best films for constellations and auroras are Fuji 800, Kodak Royal Gold 1000 or Kodak Pro PMZ 1000. If you plan on doing astrophotography while the moon is visible, try using 400-speed film such as Fuji 400 or Kodak 400. The moon brightens the sky so much that using fast film usually results in an over-exposed photo.

For pictures of planetary conjunctions at sunrise or sunset, the normal 100 or 200 speed film (the kind you would use for pets, friends, etc) can be used. I personally like to use slide film for this type of shot. Kodak Elite Chrome 200 slide film has excellent colour and I have used it was great success. Don't worry about not having a slide projector. Small hand held view screens can be purchased and are quite inexpensive.

What f-stop or lens should be used? Set the f-stop on the lens to F2.8. The f-stop determines the amount of light that reaches the film. The lower the f-stop, the more light passes through the lens onto the film. For on-tripod astrophotography, F2.8 is the best to use. If your lens is a zoom lens, set it to it's lowest setting (usually F3.5). If you have a wide-angle lens, such as a 24 or 28mm lens, try it first. If not, use the standard 50mm lens. Try zoom lenses at their widest angle. A 50mm lens is the most powerful lens you should use. The motion of the Earth becomes apparent quite quickly with higher power lenses and the result will be trailing stars in your picture.

How long of an exposure should you take? For basic constellation or aurora pictures, exposure times of 25-30 seconds will suffice. Conjunction photos at sunrise and sunset are a little bit trickier. The amount of light can change quickly. Exposure times can vary from 2 seconds upto 15 seconds. Play it safe and take shots of all different exposure times. Use a 28mm lens (or your widest) to catch the colours of the sunrise or sunset for great effect. For shooting in moonlight, aim the camera away from the direction of the moon and try exposures of about 20 seconds.

So now you are ready. The camera is on the tripod, the lens is set to F2.8 and you have picked a constellation. If you are using an SLR camera, set the exposure timer to “B”. This allows the photographer to control the length of the exposure manually. Focus at infinity (the lens racked in all the way) and then put the lens cap back on. Trip the cable release to open the shutter, carefully remove the lens cover, count away the seconds, carefully put the lens cover back on and then allow the shutter to close. Removing the lens after tripping the shutter and then reattaching it will eliminate tiny vibrations that occur when the cable release is pressed. Even tiny vibrations can cause your shot to be slightly blurred. If you don’t have a lens cap, anything dark can be used such as a hat or a piece of paper.

When you decide on a subject to photograph, try to add something to the foreground of the picture. Adding an object to the foreground, whether it is a telescope, house, tree or a person, adds to the depth of the shot. It also gives the picture your own personal "stamp". Each on-tripod picture can be unique this way.

I like to think that there are three P's in photography--- practice, planning and patience. When you first try your hand at on-tripod photography, do some practice exposures of different times to see how much of a difference a few seconds can make. Note interesting objects that may make for a unique foreground and remember where they are to plan future shots. Have some patience too. It will take a few rolls of film but eventually you can become quite adept at this. Remember too that film is cheap so don't wait until the night of a spectacular conjunction to photograph it. Take a roll or two of film a few days in advance at the site to make sure you have the exposure times correct. I once used 2 ½ rolls of film to get one picture! One roll was taken a week early as practice and the other roll and a half the night of the event.

Keep a logbook as well so you can learn from your mistakes. Record your subject, time, location, exposure time, and f-stop and lens size. After a little bit of practice, you'll soon have your own prized photo that you can proudly show off as your own. It's that simple to do.

A quick guide:

Constellations or auroras: 800 or 1000 speed film, 28 or 50mm lens set at f2.8 with exposure times of 20-30 seconds. In moonlight, 400 speed for 20 seconds.

Sunrise or sunset conjunctions: 100 or 200 speed print or slide film, 28 or 50mm lens set at f2.8 for 2-15 seconds.

Todd Carlson


Todd Carlson is an astrophotographer who lives in Toronto, Canada. His articles and astrophotographs have appeared in publications such as Sky and Telescope, the Canadian Discovery Channel, and SkyNews. Check out a few of his astrophotographs. Image 1 and Image 2 You can also visit his web site, Simple Astrophotograpy, for more information on getting started in astrophotography. .




If you have an astronomy related article you would like to have published, email it to Astronomy Digest.

Free Email

Now you can get Free Email that shows you enjoy astronomy. You can use your name, (yourname)@astronomydigest.com . Or, you can use an astronomy name like orion@astronomydigest.com . Right now there are many names available. I only ask that if you get an account that you plan to use it. And, if you no longer plan to use it, you simply delete it. This will help keep the astronomy names available for others to use. I am very pleased to offer this service for Free.

To get your Free Email account use the Free Email box located at the top right column on this ezine.


Join AllAdvantage.com

Get Paid for Reading
Astronomy Digest

Help support "Astronomy Digest" and get paid for doing it. All Advantage is a program that puts a banner at the bottom of your screen. They rotate ads when you are on the internet. You get paid 50 cents per hour. When you get someone else to join, you get 10 cents per hour for each hour they are earning 50 cents. So you can earn money and help support "Astronomy Digest" at the same time.
Join Here

I would like to thank everyone who is earning money and helping to support Astronomy Digest through AllAdvantage. I am actually receiving checks from them. I also find myself clicking on their banners and going to places on the web that I would have never found. Thanks again.


Book Review


Astrophotography for Amateurs


A complete guide to photographing the night sky, this book presents techniques ranging from compensation for the earth's rotation to long exposures for faint astronomical objects. In addition to presenting information about equipment and techniques, it also features practical hints and tips from the experts, including coverage of traditional "wet" photography, CCD imaging, and computerized image enhancement.


FREE EMAIL
(yourname)@astronomydigest.com
Email login:

Password:








Subscribe to our Newsletter. Let us notify you when our new issues are available.

Subscribe

Unsubscribe



Advertise with us

Please Email us if you would like to advertise your web site on "Astronomy Digest". We have many plans available.



Circulation

Prior Issues
Newsletter

Aug ------ 2,475
July ------ 2,472
June ----- 2,397


Prior Issues
E-Zine

Aug ------ 2,825
July ------ 2,489
June ----- 2,968



Circulation

www.SiebertOptics.bizland.com
If you enjoyed "Astronomy Digest" please visit our sponsor. Thank you.





Astronomy Digest
Directory
www.goto.com  Search made simple.
 Airline Ticket   Cars   Computers 
 Furniture   Mortgage   Music 
 Shopping   Stocks   Weight Loss 
   

Add A Link Promote Your Site



All Others

Amateur Telescope Making

Astrophotography

Classifieds

Clubs

Comets

Dealers

Events


Links

Manufacturers

Observatories

Personal


Planets/Sun/Moon

Publications


Science Fiction

Sky Charts

Space Art

Web Rings


Not 90% Astronomy



Visiting our sponsors makes "Astronomy Digest" possible. It only takes a click.



Visiting our sponsors makes "Astronomy Digest" possible. It only takes a click.










All information on this web site is copyrighted. Please do not copy information without asking permission. Permission is normally granted if you give credit to Astronomy Digest and includes the web address, http://astronomydigest.com.