# Analemma, the Slender Figure Eight in the Sky

By T. V. Antony Raj

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Definition of Analemma by Merriam-Webster: “A plot or graph of the position of the sun in the sky at a certain time of day (such as noon) at one locale measured throughout the year that has the shape of a figure 8; also : a scale (as on a globe or sundial) based on such a plot that shows the sun’s position for each day of the year or that allows local mean time to be determined.

Our Earth orbits around the Sun on an elliptical path. It also revolves around the Sun on a slant with an axial tilt of about 23.4 degrees. This leads to some interesting observational effects. One of these is the analemma, the apparent path traced by the Sun in the sky when observed at the same time of day over the course of a year.

Due to the Earth’s orbital eccentricity and its axial tilt, our Sun does not appear in the same position in the sky at the same time every day throughout the year. These two factors combine to generate the slender figure-eight, called analemma ( Greek “support”) curve.

So, the astronomers use this analemma diagram that shows the deviation of the Sun from its mean motion in the sky, as viewed from a fixed location on the Earth.

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The analemma diagram with the Sun’s path resembling a lopsided figure eight can often be found printed on globes of the Earth, usually somewhere over the Pacific Ocean where there is lots of room to print it.

The north–south component of the analemma is the Sun’s declination, and the east–west component is the equation of time. Most often, the diagrams of analemmas carry marks that show the position of the Sun at various closely spaced dates throughout the year. Analemmas with date marks are used for various practical purposes. Without date marks, they are of little use, except as decoration.

Earlier, prior to the 18th century, the term “analemma” referred to any tool or method used in the construction of sundials. Now, the term “analemma” is used in conjunction with sundials to convert between apparent and mean solar time.

Analemmas are photographed by keeping a camera at a fixed location and orientation and taking multiple exposures throughout the year, always at the same clock-time.

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The above image is a photo of an analemma posted by Giuseppe Donatiello.

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The above is an afternoon analemma photo taken in 1998–99 by Jack Fishburn in Murray Hill, New Jersey, USA. The Bell Laboratories building is in the foreground.

Although the term “analemma” is used to refer to the Earth’s solar analemma, it can be applied to other celestial bodies as well.

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# Comet Hale-Bopp: The Most Widely Observed Comet of the 20th Century

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On July 23, 1995, two independent observers Alan Hale and Thomas Bopp in the United States discovered the comet Hale-Bopp. This comet formally designated C/1995 O1 was perhaps the most widely observed comet of the 20th century, the third largest comet in the last 500 years, and one of the brightest seen for many decades. It was visible to the naked eye for a record 18 months. The previous record holder, the Great Comet of 1811, officially designated C/1811 F1, was visible to the naked eye for around 260 days.

Astronomer Alan Hale was born in 1958 in Tachikawa, Japan, when his father was serving in the United States Air Force. Four months later his father got transferred to Holloman Air Force Base outside Alamogordo, New Mexico. Hale served in the United States Navy from 1976 to 1983. In 1980, he graduated from the U.S. Naval Academy. Next, he joined the Jet Propulsion Laboratory (JPL) and worked as an engineering contractor for the Deep Space Network until 1986. As a contractor, he worked in several projects involving spacecraft, including Voyager 2. After Voyager’s encounter with Uranus, he left JPL. He attended New Mexico State University in Las Cruces. In 1992, he earned his Ph.D. in astronomy.

Hale had spent hundreds of hours searching for comets without success. On July 23, 1995, while tracking known comets from his driveway in New Mexico he chanced on the comet co-named after him just after midnight. The comet with an apparent magnitude of 10.5 was near the globular cluster M70 in the constellation of Sagittarius. He checked and confirmed that there was no other deep-sky object near M70. Next, he consulted a directory of known comets and established that none of them was in that area of the sky he had observed. He then found the object moving relative to the background stars.

As a trained astronomer who had seen about 200 comets, Hale to register his finding sent an email to the Central Bureau for Astronomical Telegrams (CBAT) in Cambridge, Massachusetts, the clearing house for astronomical discoveries operating under the auspices of Commission 6 of the International Astronomical Union (IAU). A few hours later his effort was rewarded. His new comet was officially designated C/1995 O1. His name would also be attached.

But Alan Hale was not the only observer that night.

That very night, about 400 miles (644 kilometers) away, Thomas Bopp was observing star clusters and galaxies through telescopes with friends in the desert outside Phoenix, Arizona.

Amateur astronomer Thomas J. Bopp was born in 1949 in Denver, Colorado. Later he relocated with his family to Youngstown, Ohio, where he graduated from Chaney High School in 1967. He attended Youngstown State University in Youngstown, Ohio, and has lived in Tucson, Arizona since 1980. He is a Life member of the Mahoning Valley Astronomical Society (MVAS).

Bopp was a manager at a construction materials factory. He did not own a telescope. He too noticed some fuzzy object near M70 in the constellation of Sagittarius and pointed it out to his friend Jim Steven who owned the 70 inches telescope of Dubsoniano design he was using.

Bopp had never come across a comet. Jim looked at Bopp and said, “Tom, I think you have a comet.”

He knew he had to contact the Central Bureau for Astronomical Telegrams in Cambridge, but he did not have the address with him. So, he drove back home to get it.

In the wee hours he managed to send a Western Union telegram to the Central Bureau for Astronomical Telegrams in Cambridge where its arrival was greeted with bemusement. Brian Marsden, the leading voice on a committee that has the last say laughed. “Nobody sends telegrams anymore,” he commented. “I mean, by the time that telegram got here, Alan Hale had already e-mailed us three times with updated coördinates.”

However, the following morning, the comet was confirmed as a new entity and designated as C/1995 O1. The discovery was announced in International Astronomical Union circular 6187.

Sometimes weird things happened with when major comets appeared. According to a  report, 39 members of a California cult claimed they were departing on a spaceship that was trailing comet Hale-Bopp and ate their last meal before ritually committing mass suicide. For Thomas Bopp, the comet portended a loss. As comet Hale-Bopp reached its most spectacular point in the sky, his brother and sister-in-law who had been out photographing the comet were killed in a late night car crash. “This has been the best week of my life. And, the worst,” he lamented.

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# A Near-earth Object, Asteroid 1998 QE2, Is Now Hurtling Towards Earth

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A near-earth object labeled Asteroid 1998 QE2, is now hurtling towards earth.

The asteroid about 1.7 miles (2.7 kilometers) or nine Queen Elizabeth 2 ship-lengths in size in length has the physical mass to potentially knockout life on Earth. However, we are safe as it is just flying by.

On May 31, 2013, at 20:59 UTC (1:59 p.m. Pacific / 4:59 p.m. Eastern) this asteroid will pass within 3.6 million miles (5.8 million km) of Earth – about 15 times the distance to the Moon. While this may seem a great distance for the layman, in astronomical terms it is a mere stone’s throw away. This is the closest approach the asteroid will make to Earth for at least the next two centuries.

The Massachusetts Institute of Technology Lincoln Near Earth Asteroid Research (LINEAR) program near Socorro, New Mexico, discovered this asteroid on August 19, 1998. It is officially known as Asteroid 1998 QE2. It is not named in honor of Queen Elizabeth II, or after that 12-decked, transatlantic-crossing flagship for the Cunard Line. The name was assigned by the NASA-supported Minor Planet Center in Cambridge, Massachusetts, USA. This institute assigns each newly discovered asteroid a provisional designation starting with the year of first detection, along with an alphanumeric code showing the half-month it was discovered, and the sequence within that half-month.

Though this asteroid is not of much interest to those astronomers and scientists on the lookout for hazardous asteroids, it is of interest to those who dabble in radar astronomy and have a 230-foot (70-meter) or larger radar telescopes at their disposal.

Radar astronomer Lance Benner, the principal investigator for the Goldstone radar observations from NASA’s Jet Propulsion Laboratory in Pasadena, California said: “Asteroid 1998 QE2 will be an outstanding radar imaging target at Goldstone and Arecibo and we expect to obtain a series of high-resolution images that could reveal a wealth of surface features … Whenever an asteroid approaches this closely, it provides an important scientific opportunity to study it in detail to understand its size, shape, rotation, surface features, and what they can tell us about its origin. We will also use new radar measurements of the asteroid’s distance and velocity to improve our calculation of its orbit and compute its motion farther into the future than we could otherwise.”

Asteroids come in various sizes and shapes: dog bones, bowling pins, spheroids, diamonds, muffins, potatoes, etc. Between May 30 and June 9, radar astronomers using NASA’s 230-foot-wide (70 meter) Deep Space Network antenna at Goldstone, California, and the Arecibo Observatory in Puerto Rico, are planning an extensive campaign of observations. The two telescopes with complementary imaging capabilities will enable astronomers to study 1998 QE2 and what it looks like during its brief flyby.

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# News: Russian Meteorite Shards Command ‘Stratospheric’ Prices

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The meteorite that streaked at a hypersonic speed of at least 33,000 mph across the morning sky over Chelyabinsk, Russia on Friday, February 15 at 3:20:26 UTC exploded and disintegrated about 18-32 miles above the ground. According to media reports, the shock wave from the explosion estimated as equal to 30 Hiroshima atomic bombs of August 1945, blew out the windows of 900 schools and hospitals, damaged around 100,000 homes, and injured nearly 1,200 people, It induced an undeniable trauma in many residing in and around Chelyabinsk. Fellow blogger, science fiction and fantasy author Bill Housley aptly wrote that it was similar “To Be Shot at and Missed.

Asteroid expert Don Yeomans, head of NASA’s Near-Earth Object Program Office said the object that streaked across the sky over this Russian industrial city was most likely a bolide – an exploding fireball.

The sonic blast shattered windows in and around Chelyabinsk. Scattered amid the broken glass are bits of space rock that sparked on a “meteorite rush.”

Amateur enthusiasts in Russia and scientists alike are scrambling to find bits of the meteorite worth more than their weight in gold. Dmitry Kachkalin, a member of the Russian Society of Amateur Meteorite Lovers said that enthusiasts will pay dearly for them. “The price is hard to say yet … The fewer meteorites recovered, the higher their price,” Kachkalin told Reuters. He estimates that chunks could be worth up to \$2,200 per gram — more than 40 times the current cost of gold, the news agency said.

Within hours after the explosion, many residents of Chelyabinsk and its neighborhood  had listed shards of the meteorite on classified ads sites.

International Business Times reported that a person named Andrew advertised 18 pieces of the meteor for 500 rubles (about \$16.61) each on avito.ru, – the largest Russian-language free classifieds site. “There are 18 pieces of size as a wristwatch,” Andrew wrote on the site. “You can choose as souvenirs or for stories. BOOK ME IN ADVANCE, to snap up FAST!”

Another Russian felt his rocks were more worthy, asking 300,000 rubles (roughly \$10,000) for a piece of the rock. “A piece of the meteor for sale, it’s new,” Sergey wrote, with a photo of himself holding a piece of stone.

On Monday, scientists from Ural Federal University (UrFU) in Ekaterinburg found shards of the meteorite which fell on 15 February near lake Chebarkul near Chelyabinsk, about 1500 kilometers east of Moscow. The expedition team released a photo showing 53 tiny fragments of the meteor each about 0.2-inch-long.

According to Viktor Grokhovsky, a member of the Russian Academy of Sciences‘ Committee on meteorites and the leader of the expedition, told the Interfax news service that the meteorite belonged to the class of regular chondrites. “These stone fragments contain about 10% iron. The meteor is likely to be called ‘Meteorite Chebarkul’,” the scientist said.

He then added: “We have found tiny pieces, about 50-53 in all, and each measure in millimeters. That was all we could find in the snow around the crater. The fragments we found are traces of the outer layer of the meteorite – there is a melted crust and so forth – which mean that the basic mass lies there, in the lake.”

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# The Meteorite Explosion that Shook Chelyabinsk, Russia on February 15, 2013

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By T.V. Antony Raj

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A meteor entered the Earth’s atmosphere and disintegrated in the skies over Chelyabinsk, Russia, at 7:20:26 PM PST, or 10:20:26 PM EST on February 14 (3:20:26 UTC on February 15).

At a news conference on Friday, NASA scientists said the object was a “tiny asteroid”. The trajectory of this meteor differed appreciably from the trajectory of the asteroid 2012 DA14, which hours later made its flyby of Earth, making both objects completely unrelated.

The Russian Emergency Ministry described it as a shower of meteorite debris. However, some unconfirmed reports suggested that Russian air defenses shot down a meteorite. NASA asteroid expert Don Yeomans, head of the agency’s Near-Earth Object Program Office, said that the object which exploded was most likely an exploding fireball known as a bolide.

According to the preliminary information that appeared in the media unidentified flying objects exploded over several cities in Russia, and the object at Chelyabinsk measured 49 feet (15 meters) across, weighing 7,000 tons and released 30 kilotons of energy when it exploded, and the blast waves blew out window glass of buildings in Chelyabinsk, sending dozens to hospitals, disrupted mobile services, and reportedly injured more than 1,000 people. Many dashboard videos appeared online, showing huge fireballs flying over buildings and exploding with a strong blast. Some walls of the Chelyabinsk Zinc Factory that produced 160,000 metric tons of refined zinc and alloys last year collapsed with extensive damage to the plant.

Now NASA says information provided by a worldwide network of sensors has allowed scientists to revise their estimates for the size of the object before entering Earth’s atmosphere to 55 feet (17 meters), weighing about 10,000 tons. Bill Cooke, head of the Meteoroid Environment Office at NASA’s Marshall Space Flight Center in Huntsville, Alabama said the energy released during the explosion amounted to 500 kilotons equal to that of an exploding modern nuclear bomb.

Fresh data collected from five more infrasound stations located around the world helped to generate these new estimates. The first infra-sound recording of the event took place in Alaska – over 6,500 kilometers away from Chelyabinsk. Calculations performed by Peter Brown at the University of Western Ontario, Canada, using infrasound data show the time taken by the object from entering the atmosphere to its disintegration in the air took 32.5 seconds.

Paul Chodas of NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California said, “We would expect an event of this magnitude to occur once every 100 years on average ”

The present Russia meteor is the largest reported since 1908, when a meteor hit Tunguska, Siberia.

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# Asteroid 2012 DA14 Will Flyby on February 15, 2013

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The small near-Earth asteroid named 2012 DA14 discovered on February 23, 2012, by the OAM Observatory, La Sagra in Spain with an estimated diameter of about 45 meters (about half the size of a football field) weighing about 130,000 metric tons mass probably made of stone in contrast to metal or ice is now hurtling towards the earth. It will pass within about 3.5 Earth radii of the Earth’s surface inside the geosynchronous satellite ring, located about 35,800 kilometers above the equator.

Tomorrow, February 15, 2013, when it passes within 17,200 miles (28,000 kilometers) of Earth, it will not be visible to the naked eye, but will be within range of small telescopes and solidly mounted binoculars, used by experienced observers who have access to appropriate star charts. Here is a note from NASA about the asteroid’s visibility:

On [February 15, 2013], the asteroid will travel rapidly from the southern evening sky into the northern morning sky with its closest Earth approach occurring about 19:26 UTC when it will achieve a magnitude of less than seven, which is somewhat fainter than naked eye visibility. About 4 minutes after its Earth close approach, there is a good chance it will pass into the Earth’s shadow for about 18 minutes or so before reappearing from the eclipse. When traveling rapidly into the northern morning sky, 2012 DA14 will quickly fade in brightness.

Astronomical observatories with their large telescopes would record images of the asteroid, and some observatories will be broadcasting them live online.

Slooh Space Camera will cover the asteroid’s near-approach on Friday, February 15, Slooh to cover live from the Canary Islands with the broadcast team, with several live shows free to the public starting at 6 p.m. PST / 9 p.m. EST / 02:00 UTC (2/16), accompanied by real-time discussions with Slooh Space Camera’s Paul Cox, astronomer and author Bob Berman, and Prescott Observatory manager Matt Francis. Viewers can watch live on their PC or iOS/Android mobile device.

Clay Center Observatory will be offering real-time high-definition video, from 22:00 UTC (6 p.m. EST) February 15 until 8:00 UTC (4 a.m. EST) on February 16. The video feed can be freely accessed worldwide via Clay Center Observatory’s Ustream channel. The observatory has also set up a countdown clock to show how much time remains until the tracking begins.

Bareket Observatory in Israel will be providing a free live webcast of the close approach of asteroid 2012 DA14 using a remote telescope coupled with a cooled CCD camera on February 15 from 21:00 – 22:30 local time (19:00 – 20:30 UTC, or 2 p.m. – 3:30 p.m. CST).

Virtual Telescope Project, which calls itself “the most active facility in the world in astronomical science and education,” will also be following 2012 DA14 on February 15, 2013.

Will anything happen when asteroid 2012 DA14 comes close to Earth? Nothing. According to Paul Chodas, Jon Giorgini and Don Yeomans of NASA/JPL Near-Earth Object Program Office the asteroid will not impact the Earth on February 15, 2013.

The asteroid will have no effect on the tides. It will not cause volcanoes to erupt. It will not trigger earthquakes and tsunamis. Though the asteroid will just hurtle closely past Earth only 17,000 miles away – within the orbits of geosynchronous satellites, most of us will not see it, and we will not be aware of it at all.

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# A Near-Earth Object, Asteroid 2012 DA14 Now Hurtling Towards Earth

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Comets and asteroids that enter the Earth’s neighborhood nudged by the gravitational attraction of nearby planets are known as near-Earth Objects (NEOs).

One such near-Earth asteroid named 4179 Toutatis formerly known as 1989 AC was discovered by Christian Pollas on January 4, 1989, at Caussols, France. On
December 12, 2012, this asteroid with a shape of a “malformed potato” tumbled through space like a fumbled football, within 4.3 million miles from Earth.

Another near-Earth asteroid discovered on February 23, 2012, by the OAM Observatory, La Sagra in Spain with an estimated diameter of about 45 meters (about half the size of a football field) weighing about 130,000 metric tons mass probably made of stone in contrast to metal or ice is now hurtling towards the earth.

On February 15, 2013, this asteroid labeled 2012 DA14 will pass within about 3.5 Earth radii of the Earth’s surface inside the geosynchronous weather and communication satellites ring, approximately 35,800 kilometers above the equator.

Even though asteroids like 2012 DA14 fly past Earth almost every 40 years they impact with our planet only every 1200 years or so. Don Yeomans, Paul Chodas, and Jon Giorgini of NASA/JPL Near-Earth Object Program Office after predicting the asteroid’s path have declared that according to their observations, there is no chance that the asteroid might be on a collision course with the Earth, and it will safely fly past Earth’s outer ring of satellites on February 15.

“Since regular sky surveys began in the 1990s, we’ve never seen an object this big gets so close to Earth,” Don Yeomans said.

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# December 21, 2012: YIPEE! THE WORLD IS STILL WHOLE!

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. By T.V. Antony Raj

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### It’s December 21, 2012: THE WORLD HAS NOT ENDED!

If you can read this, it means the Good Times have begun!

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According to this calendar, the Good Times still continue!

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So, there can be only one agenda in a Friday meeting!

I have borrowed the above images from the Facebook page of
Kingfisher – The King of Good Times!

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# December 21, 2012: Winter Solstice in the Northern Hemisphere or Is It Doomsday 2012?

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The astronomical event known as the solstice occurs when the Sun reaches its highest or lowest excursion point relative to the celestial equator on the celestial sphere. This event occurs twice a year.

On the day of the solstice, at local solar noon, the Sun appears to have reached its highest or lowest annual altitude in the sky above the horizon.

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For any place other than the tropics the solstice day in summer is the longest day of the year, and the solstice day in winter is the shortest day of the year.

During the winter solstice in the Northern Hemisphere, also known as the Southern solstice that occurs on December 21st to 22nd, the Sun at noon would appear at its lowest altitude above the horizon, namely, at its southernmost point in the sky. On the other hand, in the Southern Hemisphere, the winter solstice also known as the Northern solstice occurs on June 20th to 21st each year.  On this day, the Sun appears at its northernmost point in the sky.

The axis of rotation of the earth directed towards the same point in the heavens is the result of its axial tilt and the gyroscopic influences of its daily rotation. As the Earth orbits around the Sun, the polar hemisphere facing the Sun encountering summer would after six months face away from the Sun to  endure the winter.

The solstices last only a moment in time. This year, winter solstice would occur today, December 21, 2012 at 11:12 AM UTC (6:12 AM EST; 4:42 PM IST).

Worldwide, interpretation of the winter solstice varies from culture to culture. However, all recognize the rebirth of the Earth that involves religious festivals, rituals, and other celebrations. The following lists a few observance believed to be directly linked to the winter solstice.

This brings us to the Doomsday Prophecy attributed by some to the Mayan Calendar. Though the Mayans never predicted that the world would end today, December 21, 2012, some doomsday soothsayers have been touting all these days that around 80 percent of the world population would be wiped out on this fateful day. Many who believe these scare mongers have left their homes; they have traveled to places where they think their chances of survival will be better.

Ten hours ago, I read an article titled “Global doomsday hot spots draw believers, revelers” by Vanessa Gera where she describes some of the world’s key doomsday destinations and other places marked by fear and fascination.

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# Day Before Yesterday NASA Released Video: “Why the World Didn’t End Yesterday”

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. By T.V. Antony Raj

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NASA is so sure the world won’t come to an end on December 21, 2012, that they already released day before yesterday a “Didn’t We Say So!” video titled “ScienceCasts: Why the World Didn’t End Yesterday” on December 11th, itself.