MAC January 2011 Magazine by MAC Realta

Midlands Astronomy Club Magazine

Sky Guide - Beginner’s targets for January For the naked eye in January, we have another meteor shower to look forward to. The Quadrantids generally begin on January 1st and end on January 7th, with the maximum occurring this year on the evening of the 3rd. The shower coincides with the new moon of January so moonlight will not interfere with observing at any hour of the night. Observers in the Northern Hemisphere can see around 60 meteors per hour or more at maximum. Look for meteors radiating from the constellation Bootes near the plough/big dipper. Telescope Targets Many of Autumn's targets are still available early in the evening. See November's and December's picks for these. F or J a nua r y, Or ion r e ig ns supreme in the sky. One of the brightest and best nebula is the Great Orion Nebula (M42). This is also one of the easiest (if not the easiest) deep sky targets to locate. Hanging from the belt of Orion (3 stars in a row of equal magnitude) are 3 more stars (his sword). The second "star" of these is the nebula. Folks with good eyes can make out colour (typically green) at higher powers. Push the power up and look for the 4 stars in the centre that provide the luminosity for this nebula. These are known as the trapezium and I have seen

them easily with my 4.5" reflector. In the same telescopic view, more or less attached to M42 is M43, a small patch of nebulosity separate from M42. We also have a nice multiple star system in Orion, Sigma Orionis. To find this system, use the eastern most star of Orion's belt (Alnitak). Just below Alnitak is a dimmer star, this is Sigma Orionis. Focus in on this star at high power, and it should split into what looks like 3 separate stars. In most small telescopes, Sigma Orionis will look like a triple star. Also in the same field of view is another triple star system known as Struve 761.

Above: Orion includes the prominent asterism known as the 'belt' of Orion: three bright stars in a row. Surrounding the belt at roughly similar distances are four bright stars, which are considered to represent the outline of the hunter's body. Descending from the 'belt' is a smaller line of three stars (one of which is in fact not a star but the Orion Nebula), known as the hunter's 'sword'.

Also up for January is a super-nova remnant (SNR), the Crab Nebula . T his is the remains of a star that exploded in 1054AD which makes this a youngster in astronomical terms. Up and to the right of Orion there is a "V" shaped grouping of stars (the head of Taurus the Bull). The Hyades are part of this V as well. A very bright orange-red star (Aldeberan) sits as the third star in the line of the V. follow this line out to where

Club Observing: Remember the next club meets every first Friday of the month for our observing sessions held in the MAC grounds. If you wish to be informed of these sessions please email your name and mobile number to midlandsastronomy@gmail.com who will confirm if the session is going ahead (depending on weather).

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Alnitak

Also in Orion are many double stars. Alnitak is a tough double to split with a separation of only 2.4 arc-seconds. Mintaka (the star on the right side of the belt). The companion is somewhat dim glowing at only 7th magnitude.

Club Notes

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Issue 20 - January, 2011

Crab Nebula

the V seems to end at another fairly bright star (Zeta Tauri). Go up toward the other side of the V about a fifth of the distance toward the other star (El Nath) and you should see a dim "fuzz." Dark skies are needed for this one though. Planets Jupiter continues to be available in the early evening with Saturn following Jupiter across the sky. Saturn can be located in Leo this month. With the planet’s ring plane almost edge on, this is not a good time to try and observe the rings. It is however a good time to try and observe the smaller satellites and details on the planet’s

Right: The Crab Nebula (M1) in the constellation Taurus. surface with the rings out of the picture. Venus is visible in the early morning hours blazing at magnitude -4.1. Venus shows phases through the telescope similar to the moons phases. Watch Venus weekly as it grows in apparent size and the phases shift. W e l l , t h a t ' s a b ou t i t fo r January's picks although with a good star map there are tons of wonderful sights to be had on cold winter nights. Clear skies and good hunting!

By Kevin Daly http://members.aol.com/kdaly10475/index.html

Latest Astronomy and Space News Kids Astronomy Quizzes and Games Monthly Sky Guide

Midlands Astronomy Club Magazine

The three bright stars in Orion's belt stand in a nearly vertical line above the snow covered road at the bottom. Hanging from his belt, the stars and nebulae of the Hunter's sword are visible lower and to the right. Yelloworange Betelgeuse is the brightest star on the image left. As winter progresses in Earth's northern hemisphere, Orion will rise earlier and so appear continually higher in the sky at sunset.

Credit & Copyright: Brendan Alexander

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Kids Section Kids Korner ....................................................................... 10

Quizzes and Games

the to

first visit

4. Saturn takes about ______________ Earth years to make one revolution around the Sun. 1 12 24 29

Exercise your brain ............................................................ 11

Monthly Sky Guide Beginners sky guide for January ......................................... 12

5. Saturn's atmosphere is mostly made up of ______________. Sulfur and Hydrogen Nitrogen and Oxygen Hydrogen and Helium Hydrogen and Nitrogen

8. Saturn’s largest satellite is ____________. Iapetus Titan Dione Rhea

9. There is a large impact crater on Saturn's moon Mimas, who is it named after? Huygens Kepler Herschel Newton

10.What satellite of Saturn has very contrasting colouration? Mimas Dione Enceledus Iapetus

1 1

8 4

6 2

7 4

7 5 7

3 8

Check your answers

thin. If you could lump all of the ring material into one body it would be about 100 kilometres across, very small indeed.

Front cover image: Orion always comes up sideways ... and was caught in the act earlier this month by over a snowy landscape in Donegal. To compose this serene picture, the photographer found a picturesque setting to the east, waited until after sunset, and then momentarily lit the foreground with a flashlight.

Guerin Division Encke Division Cassini's Division Maxwell Division

Answer 1: The correct answer was Rings. Saturn's rings were actually detected by Galileo. He noted Saturn's odd shape, but he couldn't determine what was causing it. It was not until 1659 that Christiaan Huygens figured out that they were rings, although at first no one believed him.

Voyager 1 Voyager 2 Pioneer 10 Pioneer 11

7. The "dark" region between Saturn's two brightest rings is called ___________.

Answer 7: The correct answer was Cassini's Division. Encke's division is between the A and F ring. Maxwell division is between the B and C ring and the Guerin division is between the C and D ring.

'Weird' Galaxy with a Cold-Quasar Centre Discovered ............ 8

The "Death Star" Galaxy ...................................................... 9

is of

.69 .89 1.7 6.5

3. What was spacecraft Saturn?

M33′s “Object-X” ................................................................. 9

2. Saturn's density __________ that water.

Did Iapetus have its own mini moon? ................................... 8

Answer 8: The correct answer was Titan which is the only satellite that has a fairly thick atmosphere.

Tips for using your first Telescope ....................................... 6

Answer 2: The correct answer was .69. Saturn's density is so low, that if you could find a body of water large enough, Saturn would float!

Venus has a Moon? ............................................................. 5

Answer 3: The correct answer was Pioneer 11 which visited Saturn in 1979. The Pioneer spacecraft were nearly fried at Jupiter by the ions trapped in Jupiter's magnetic field.

You can see more about the club and its events on www.midlandsastronomy.com or contact the club via e-mail at midlandsastronomy@gmail.com Meetings are informal and are aimed at a level to suit all ages.

Stars shrouded in glittering Zirconium light up the sky ........... 5

Answer 9: The correct answer was Herschel. This impact crater is some 130 kilometres across, virtually a third of the diameter of the satellite. The impact, most likely, almost destroyed Mimas. Herschel discovered Mimas in 1789.

Saturn moon has ice volcano - and maybe life? ..................... 4

Satellites Craters Sunspots Rings

1 kilometre 10 kilometres 32 kilometres 87 kilometres

Answer 4: The correct answer was 29. Saturn is so far away from the Sun, some 1,429,000,000 kilometres, that it takes over 29 years to orbit the Sun. Saturn is over 9 times further away from the Sun than the Earth.

China poised to explore Mars ............................................... 3

SUDOKU

6. How thick are Saturn's rings?

Answer 5: The correct answer was Hydrogen and Helium. Like Jupiter, Saturn's atmosphere consists mainly of Hydrogen (about 75%) and Helium (about 25%).

10-year-old girl discovers a Supernova ................................. 3

1. Saturn was the first planet known to have ____________.

Answer 10: The correct answer was Iapetus. Its leading hemisphere is extremely dark. The trailing hemisphere is almost as bright as Europa, Jupiter's satellite. The difference was noted by Cassini. He could see Iapetus on one side of Saturn but not on the other side of Saturn. There are several theories as to why Iapetus has such difference in coloration, but more research is needed.

Latest Astronomy and Space News

All are welcome to attend. It also holds infrequent Observing Nights at its Observing Site in Clonminch, or at a member’s house (weather permitting) on the first Friday of every month..

Exercise your brain

contents

Answer 6: The correct answer was 1 kilometre. Saturn's rings are incredibly

MAC meets on the first Tuesday of the month in the Presbyterian Hall, High Street, Tullamore from 8pm.

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Midlands Astronomy Club Magazine

Kid’s Korner Hail King of the Ice Dwarfs! Which sentence describes Pluto?

best

1. Pluto is the largest of the "ice dwarfs" in our solar system. 2. Pluto is just one of many icy objects in a distant area of our solar system.

More Fun Facts About Pluto: Pluto is only about half the width of the United States. Charon is about half the size of Pluto. Charon is the largest moon compared to the body it orbits (whether planet or dwarf planet) of any moon in the solar system.

the nice, orderly plane where all the other planets orbit. (Mercury has a slightly lop-sided orbit, although not nearly so much as Pluto's.) Compared to most of the planets and their moons, the whole PlutoCharon system is tipped on its side. Like the planets, Pluto's spin axis stays pointed in the same direction as it orbits the Sun. But unlike all planets except Uranus, Pluto is tipped on its side. The planets' axes of rotation stand more or less upright from the plane of their orbits.

Well, just pick the answer you like best, because they are all true!

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At Pluto's current distance from the Sun, the temperature on its surface is about 400 degrees below zero Fahrenheit! It will get even colder as it moves farther from the Sun. From Pluto, the Sun looks like just a bright dot in the sky, the brightest star visible. The light from the Sun is as bright on Pluto as the light from the full Moon is on Earth. If you weigh 100 pounds on Earth, you would weigh only 7 pounds on Pluto!

10-year-old girl discovers a Supernova

If you lived on Pluto, you would see Charon from only one side of the

Kathryn Gray by her father's telescope.

Kathryn Aurora Gray is taking her new celebrity in stride after becoming the youngest person ever to discover a supernova. A ten-year old girl from Canada has discovered a supernova, making her the youngest person ever to find a stellar explosion. The Royal Astronomical Society of Canada announced the discovery by Kathryn Aurora Gray of Fredericton, New Brunswick, (wonderful middle name!) who was assisted by astronomers Paul Gray and David Lane. Supernova 2010lt is a

magnitude 17 supernova in galaxy UGC 3378 in the constellation of Camelopardalis, as reported on IAU Electronic Telegram 2618. The galaxy was imaged on New Year’s Eve 2010, and the supernova was discovered on January 2, 2011 by Kathryn and her father Paul. The observations were made from Abbey Ridge Observatory, and this

is the third seen from this observatory. It was Lane’s fourth supernova discovery, Mr. Gray’s seventh, and Kathryn’s first. The discovery was soon verified by Illinois-based amateur astronomer Brian Tieman and Arizona-based Canadian amateur astronomer Jack Newton.

Pluto orbits in a far-out region of the solar system called the Kuiper (rhymes with viper) Belt. There are lots of icy, rocky objects out there. But they are so far from the Sun they are really hard to see, even with powerful telescopes.

4. All of the above.

One thing is certain. Pluto and its neighbourhood are very peculiar. If scientists could unravel some of their mysteries, we would know more about how our solar system formed.

planet. Charon's orbit around Pluto takes about six and one-half Earth days. Pluto's day (that is, one complete rotation) takes exactly the same amount of time. So, Charon always "hovers" over the same spot on Pluto's surface, and the same side of Charon always faces Pluto.

If you lived on Pluto, you'd have to live 248 Earth years to celebrate your first birthday in Pluto-years.

3. Pluto and its large, orbiting companion object Charon, are tipped on their sides.

Until recently, Pluto was the ninth Almost all the planets travel around planet from the Sun. It was also the the Sun in nearly perfect circles. smallest planet. But not anymore! But Pluto does not. It takes an oval -shaped path with the Sun For a long time, scientists have been nowhere near its centre. What's trying to decide how to define the more, its path is quite tilted from word "planet." If Pluto is a "planet," many other recently discovered objects nearly as large would also be planets. There is no telling how many "planets" kids would have to memorize someday! So, for that reason, be glad the scientists have finally decided. Pluto is no longer a planet. Instead, it is now called a dwarf planet.

Midlands Astronomy Club Magazine

Let's Go There! We will finally get to visit Pluto, Charon, and the Kuiper Belt! On January 19, 2006, NASA launched a robot spacecraft on the long journey. This mission is called New Horizons. The spacecraft will arrive at Pluto in the summer of 2015, then go on to study other objects in the Kuiper Belt from 2018 to 2022.

With New Horizons, we will visit and learn about the objects at the very edge of our solar system. They may help us understand how our solar system formed.

Above: An image of Supernova 2010lt discovered by Kathryn Aurora Gray.

China poised to explore Mars The Chinese National Space Administration has drawn up a technical plan for an independent Mars orbiter exploration project, space technology experts said. Based on research conducted by the China Academy of Space Technology, the plan envisions a launch date as early as 2013, Huang Jiangchuan, a scientist with the academy, was quoted by Beijing-based Science and Technology Daily. The Mars probe will be sent to an Earth-Mars transfer orbit first, and then fly about 10 months before entering an elliptical orbit around Mars. The Mars exploration will last one to two years, he said.

The government has not yet approved the project. But Yang Baohua, president of the academy, was quoted by Guangming Daily as saying that a step-by-step exploration of the Red Planet is 'no doubt the future trend and mission for China'. Ye Peijian, chief designer of the nation's first moon probe, told

Since a supernova can outshine millions of ordinary stars, it can be easy to spot with a modest telescope, even in a distant galaxy like UGC 3378 which is about 240 million light-years away. The trick is to check previous images of the same location to see if there is any changes. That’s what Kathryn was doing for the images of the galaxy taken by her father. China Daily that the technical plan does not represent the world's most advanced technologies in deep space exploration. 'But it will be the most reliable plan available which can help us achieve the goal in the shortest time,' he said.

Supernovas are stellar explosions that signal the violent deaths of stars several times more massive than our sun, and can be used to estimate the size and age of our universe. Supernovas are rare events. The Chandra X-Ray telescope found evidence of a supernova explosion that occurred about 140 years ago in our galaxy (although no one saw the explosion take place), making it the most recent in the Milky Way. Previously, the last known supernova in our galaxy occurred around 1680, an estimate based on the expansion of its remnant, Cassiopeia A. http://www.universetoday.com

billion yuan (S$272.8 million) spent on Chang'e-1, he estimated. http://www.dailygalaxy.com

He said that China has proven its ability in spacecraft design through the two lunar satellites, Chang'e-1 and Chang'e-2. Together with a deep space network under construction and the progress in the launch vehicle system, China can target Mars now, he said. The direct investment needed for this project will be less than the 1.4

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Midlands Astronomy Club Magazine

Saturn moon has ice volcano - and maybe life? Saturn's moon Titan has long been suspected of sporting ice volcanoes. Now NASA pictures appear to confirm at least one huge, dormant "cryovolcano"—and perhaps more. If the evidence bears out, it might represent the best evidence yet that life could exist on Saturn's biggest satellite. Not unlike the volcanoes of Hawaii, the supposed ice volcano, known as Sotra Facula, rises 5,000 feet ( 1 ,5 00 m e te r s) a b ove the surrounding plain in a large, gently shaped dome, according to the mountain's discoverer, geophysicist Randolph Kirk. The feature had previously been seen as a circular bright spot, nicknamed "The Rose," in radar and infrared pictures of Titan taken by NASA-ESA's Cassini probe. But it wasn't until Cassini passed over the site a second time that scientists realized Sotra Facula is a circular mountain 40 miles (70 kilometres) across. "Shocked" by Saturn Moon Volcano Evidence Because the two flybys viewed the apparent ice volcano from different

angles, the researchers were able to make a topographical map. Converted into a 3-D video, the combined images allowed scientists to virtually fly over the region at low altitude, as though on an airplane tour. "I was shocked when I saw the video and suddenly realized what we were looking at," said Kirk, of the U.S. Geological Survey's Astrogeology Science Centre in Flagstaff, Arizona. The 3-D computer model also revealed at least two more giant mountains, one with another big crater. The mountains form a chain several hundred miles long, flanked by lowlands that appear to be enrobed in lava flows. "That's a combination of features

you can't make any way other than by volcanism, we believe," said Kirk, who announced the find at a meeting of the American Geophysical Union (AGU) in San Francisco. Planetary scientist Jeffrey Kargel agrees that a volcano is by far the best explanation. "They have all their ducks in a row, short of having an actual sample form the surface that we could analyse," said Kargel, of the University of Arizona, Tucson, who was not part of the study team. Ice Volcano Spews Life Onto Saturn Moon? The presence of an ice volcano would increase the chances that Titan has the building blocks for life. Lava from an ice volcano, the thinking goes, would contain liquid water. That water could react with chemicals called tholins—molecules produced in Titan's atmosphere when UV sunlight irradiates compounds such as methane or nitrogen. These reactions could produce important chemical precursors to

Midlands Astronomy Club Magazine life, said planetary scientist Catherine Neish, who wasn't involved in the discovery. In separate research also presented at the AGU meeting, Neish found that room temperature water laced with tholins will create amino acids, the building blocks of proteins, within days—much less time than it would take "cryolava" to freeze on the Saturn moon. According to Neish, of Johns Hopkins University, "the reactions are easy and quick"—and they require temperatures only a bit above freezing. That's important, the University of Arizona's Kargel added. "Volcanoes on Earth are destroyers of life," he said. "But on Titan, cryovolcanism would represent perhaps the very liquids that would form the habitat for life." And if by chance there is life in warm zones in subterranean Titan, the volcanoes might carry traces of life-forms to the surface, where future explorers might someday find the frozen remnants, he added. Cryovolcano or Asphalt Volcano? Without physical samples of Sotra Facula, though, we can’t be absolutely sure its lava contains water. Despite the fact that Titan is largely covered in water ice, "the presence of things that look like volcanoes doesn’t mean" they spewed watery lava, said Ralph Lorenz, a planetary scientist from Johns Hopkins University who wasn't part of the cryovolcano study. The University of Arizona's Kargel said that, for example, the Titan volcanoes might have formed from oozing hydrocarbons such as asphalt—a not unheard-of possibility. For one thing, Titan is believed to have lakes filled with hydrocarbons, such as liquid methane. For another, Kargel said, "we recently found asphalt volcanoes off the coast of Santa Barbara.

www.news.nationalgeographic.com Above: Topographic computer model of Sotra Facula, an apparent ice volcano on Saturn's moon Titan.

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M33′s “Object-X” Often times, objects that are unremarkable in one portion of the spectra, can often be vivid in others. In M33, the Triangulum Galaxy, a star that’s barely visible in the optical, stands out as the second brightest source (and single brightest single star) in the mid-infrared. This unusual star has been the target of a recent study, led by Rubab Khan at the Ohio State University and may help astronomers to understand an unusual supernova from 2008. The supernova 2008S occurred February first in NGC 6946, the Fir ewor ks Galax y. Sinc e it happened in a galaxy that is relatively nearby, astronomers seized the opportunity to explore the progenitor star in archival images. Yet images from the Large Binocular Telescope and other optical observatories could not find a star that could be identified as a parent. Instead, the detection of the star responsible came from Spitzer, an infrared observatory. Observations from this instrument indicated that the star responsible may have been unexpectedly low mass for such a powerful explosion leading other astronomers to question whether or not SN 2008S was a true supernova, or merely an impostor in the form of an eruption of a Luminous Blue Variable (LBV), which tend to be more massive stars and would be in stark contradiction to the Spitzer findings. Yet, regardless of the nature of the nature of SN 2008S, teams all seemed to agree that the progenitor had only been detected in the infrared because it was veiled by a thick curtain of dust. So to help better understand this class of dusty stars, astronomers have been working to uncover more of them, against which they can test their hypotheses. To find these objects, astronomers have been searching the infrared portion of the spectrum for objects that are exceptionally bright yet lack optical counterparts. The brightest of the stellar sources in M33 features faint star in the red portion of the optical spectrum from the Local Group Galaxies Survey published in 2007, but no star at all in archival records with similar limiting magnitudes from 1949 and 1991. The authors of the

new study have dubbed this odd source, Object-X. The team rules out the possibility that the object could be a young stellar object (YSO), blocked by a thick dust disc along the line of sight, noting that models of even the thickest dust discs still predict more light to be scattered back along the line of sight. Instead, the team concludes that Object-X must be a self-obscured star that has undergone relatively recent mass loss which has cooled to form either graphite or silicate dust. Depending on which type of dust is predominant, the team was able to fit the data to two wildly different temperatures for the star: either 5000 K for graphite, or 20,000 K for the silicate. In all cases, the predicted mass for the central star was always greater than 30 solar masses.

Above: The Triangulum Galaxy (M33) is a spiral galaxy approximately 3 million light years from Earth and is sometimes informally referred to as the Pinwheel Galaxy. It is one of the most distant permanent objects that can be viewed with the naked eye. In general, there are two mechanisms by which a star can eject material to form such a curtain. The first is through stellar winds, which increase as the star enters the red giant phase, swelling up and lowering the force of gravity near the surface. The second is “impulsive mass ejections” in which stars shudder and throw mass off that way. A classical example of this is Eta Carinae. The team predicts from the features they found, that Object-X is most likely a cool hypergiant. The fact that the

The "Death Star" Galaxy The supermassive black hole at the centre of a distant galaxy is blasting a smaller neighbour with a violent energy jet— earning it the Star Wars moniker, the "Death Star" galaxy, one of two galaxies orbiting each other at an unusually close distance. The pair is located in the constellation Serpens about 1.4 billion light-years from Earth. The jet may also lead to a new burst of star and planet formation. "The origin, propagation, and energy dissipation of jets are among the most important unsolved problems in modern astrophysics," said lead study author Daniel Evans of Harvard

University in Cambridge, Massachusetts. Jets may hold also vital clues to figuring out how energy was transported in the formative stages of the universe, he added. The galaxies were found using some of science's most powerful technology: NASA's Chandra X-Ray Observatory, the NASA/ESA Hubble Space Telescope, the National Radio Astronomy Observatory's Very Large Array, and the U.K.'s MERLIN array of radio telescopes. The images show a jet reaching out like a tentacle from the larger galaxy—which is about the size of the Milky Way—about a million light -years into space. About 20,000 light-years along the way, the jet encounters the smaller galaxy.

star was completely obscured until very recently hints that the mass loss is not constant (as stellar wind), but patchy, coming from frequent eruptions. As the shell of dust expands, the star should reemerge in the optical, becoming visible again in the next few decades.

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That galaxy—which is also thought to harbour a supermassive black hole—has swung itself into the path of the jet and is rotating clockwise toward it. Collisions between nearby galaxies are relatively common in the universe. Black hole jets are less common, though scientists have detected many of them. But both at the same time had been unheard of until now. "The difference is that one of the two galaxies is ejecting the relativistic jet—and to have it crash into the side of the other galaxy is a really rare occurrence," Evans said.

www.dailygalaxy.com

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Midlands Astronomy Club Magazine

Did Iapetus have its own mini moon? There’s a new theory for why Saturn’s moon Iapetus looks like a walnut. The moon has a mysterious large ridge that covers more than 75 percent of the moon’s equator. Figuring out the reason for the ridge, say researchers from Washington University in St. Louis, has been a tough nut to crack. But they propose that at one time Iapetus itself had its very own moon, and the orbit of this minimoon-around-another-moon would have decayed because of tidal interactions with Iapetus, and those forces would have torn the subsatellite apart, forming a ring of debris around Iapetus that would eventually slam into the moon near its equator. The ridge on Iapetus is 100 kilometres (62 miles) wide and at place, 20 kilometres (12 miles) high. (The peak of Mount Everest, by comparison, is 8.8 km (5.5 miles) above sea level.) Iapetus itself is 1,470 km across, and is the 11th largest moon in the Solar System. Professor William McKinnon and his former doctoral student, Andrew

Dombard — now from the University of Illinois Chicago — came up with this idea. “Imagine all of these particles coming down horizontally across the equatorial surface at about 400 meters per second, the speed of a rifle bullet, one after the other, like frozen baseballs,” said McKinnon. “Particles would impact one by one, over and over again on the equatorial line. At first the debris would have made holes to form a groove that eventually filled up.” “When you have a debris ring around a body, the collisional interactions steal energy out of the orbit,” Dombard said. “And the lowest energy state that a body can be in is right over the rotational bulge of a planetary body — the equator. That’s why the rings of Jupiter, Saturn, Uranus and Neptune are over the equator.” “We have a lot of corroborating calculations that demonstrate that this is a plausible idea,” added Dombard, “but we don’t yet have any rigorous simulations to show

'Weird' Galaxy with a Cold-Quasar Centre Discovered NASA's Chandra X-ray Observatory has spotted a strange, distant galaxy cluster about 8 billion light-years from Earth with a cosmic quasar core that is amazingly cold. This particular quasar is called 3C 186, making it the most distant galaxy cluster with a quasar ever seen. Quasars, among the brightest objects in the universe, form at the central regions of some galaxies, where supermassive black holes feed on matter so furiously that the remaining stuff around them generates tremendous energy transmissions that span the entire electromagnetic spectrum, including radio waves, light and X-rays. But the heart of the galaxy cluster

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studied by the Chandra observatory is cold in astronomical terms. with the gas at the cluster's centre is a mere 30 million degrees Fahrenheit (16.7 million degrees Celsius), while temperatures at the outskirts tops out around 80 million degrees Fahrenheit (44.4 million Celsius).

Midlands Astronomy Club Magazine

the process in action. Hopefully, that’s next.”

Stars shrouded in glittering Zirconium light up the sky

Other ideas for how the ridge was created are volcanism or mountainbuilding forces. “Some people have proposed that the ridge might have been caused by a string of volcanic eruptions, or maybe it’s a set of faults,” said McKinnon. “But to align

There's a star in the sky that sparkles like a diamond— thanks to vast amounts of zirconium in its atmosphere, astronomers have announced.

Above: A ridge that follows the equator of Saturn's moon Iapetus gives it the appearance of a giant walnut. This image was taken by the Cassini spacecraft. Left: A closeup of Iapetus' ridge. In 2007, Cassini flew within a few thousand kilometres of Iapetus' surface to take this dramatic image. it all perfectly like that — there is just no similar example in the solar system to point to such a thing.” Dombard said there are three critical observations that any model for the formation of the ridge has to satisfy: Why the feature is sitting on the equator; why only on the equator, and why only on Iapetus. Dombard says that Iapetus’s Hill sphere — the zone close to an astronomical body where the body’s gravity dominates satellites — is far extreme drop in temperature occurs because intense X-ray emission from the gas nearer the core cools it down, the researchers added. Because it took eight billion years for the cluster's light to reach Chandra's instruments, researchers are seeing it as it appeared when the universe was still relatively young — less than half its current age of about 13.7 billion years.

P r e vious ob s e r va tions ha ve revealed large numbers of clusters with strong cooling cores closer to Earth, less than about six billion light-years. But they appear to be more rare the farther away researchers look. One reason for this may be that more distant galaxy clusters — which are younger, since astronomers are In quasar physics, "it's positively seeing them at an earlier point in chilly," researchers said. The the universe's history — merge

bigger than that of any other major satellite in the outer solar system, accounting for why Iapetus is the only body known to have such a ridge. “Only Iapetus could have had the orbital space for the sub-satellite to then evolve and come down toward its surface and break up and supply the ridge,” he says.

www.universetoday.com more often with other clusters or galaxies, researchers said. This cluster was found fortuitously via a relatively modest Chandra survey. So it's possible that many other similar objects exist at large distances, researchers said. The ima ge of the clus ter surrounding quasar 3C 186 is a composite. It includes a new image from Chandra showing X-ray emissions from gas surrounding the point-like quasar near the center. Optical data from the Gemini telescope in Chile contribute views of nearby stars and galaxies.

Dubbed LS IV-14 116, the faint, blue star lies about 2,000 lightyears from the sun. Detailed new measurements reveal the star to be the most zirconium-rich known to date, with levels more than 10,000 times higher than those in our sun. While real diamonds are made of carbon, jewellers make false diamonds out of zirconium dioxide crystals, aka cubic zirconia. The mineral zirconium silicate, or zircon, is also widely used as a gemstone. In addition to zirconium, astronomers studying LS IV-14 116 found chemical signatures for high amounts of three other elements rarely seen in stellar atmospheres: strontium, germanium, and yttrium. "It really is quite an oddball," said team member Simon Jeffery of Armagh Observatory in Northern Ireland. An In-Between Star Jeffery and colleagues found the high amount of zirconium while studying the chemistry of LS IV-14 116. Previous measurements had indicated the star is a rare, heliumrich hot subdwarf. When less massive stars die, they swell up and start shedding their outer layers of gas, becoming red giants. When all the gas is released, the leftover core of the dead star is called a white dwarf. Hot subdwarfs represent a phase of evolution for some stars that comes between red giants and white dwarfs, so studying them will give scientists greater insight into how stars live and die.

www.dailygalaxy.com U s ing t he A ng l o- A us tr a l i a n Telescope at Siding Spring Observatory in New South Wales, the team took a closer look at LS IV -14 116's spectral lines, the

frequencies of light emitted by the star, as determined by the elements and molecules present. The spectral line for zirconium was not only strong, it corresponded to a form of the metal that exists only at temperatures above 20,000 degrees Celsius. This form had previously never been seen in any astronomical object. More Zirconium Stars Out There? Based on models of the star's atmosphere, the team concluded that the four unusual elements are clustered in thin clouds around the star, which have settled out in layers according to their masses. Normally radiation emitted by the star would churn the elements in the star's atmosphere. But this star is cooling very slowly, and there are few external influences. "The atmosphere is very still on these kinds of star, with little mixing occurring," Jeffery said. As

Above: A sample of the mineral zirconium silicate, aka zircon. the temperature of the star changes, however, so too does the level of radiation, meaning that atmospheric elements will move to new levels to keep in balance with the radiation. These changes will take many thousands of years, the scientists suspect. Previous studies had shown that two other oddball stars have high abundances of elements not often seen in stellar objects, including nickel, iron, and vanadium. Jeffery and his colleagues speculate that

Venus has a Moon?

place in orbit around the Sun where at its closest it wanders inside the orbit of Mercury and at its furthest it reaches just outside the orbit of the Earth. It is now in a 1:1 orbital resonance with Venus.

“Wait a minute; back up”, I hear you ask. “Venus has a Moon?” Of course it does. Well, kind of… Let me explain.

An orbital resonance is when two orbiting bodies exert a regular, periodic gravitational influence on each other due to their orbital periods being related by a ratio of two small numbers. For example, Pluto and Neptune are in an orbital resonance of 2:3, which simply means for every two times Pluto goes around the Sun, Neptune makes three trips. In the case of Venus and 2002 VE68, they both take the same time to orbit the Sun once. They are in a 1:1 orbital resonance. So by definition, 2002 VE68 is considered a quasi-satellite of Venus. Often these resonances result in an unstable interaction, in which the bodies exchange momentum and shift orbits until the resonance no longer exists. In this case, scientists believe 2002 VE68

It has the rather unfortunate name of 2002 VE68. That is because it was discovered on November 11, 2002 by LONEOS, the Lowell Observatory Near Earth Object Search. 2002 VE68 is an earth orbit -crossing asteroid that has been designated a Potential Hazardous Asteroid by the Minor Planet Centre. 2002 VE68 used to be a run of the mill, potential impact threat, Near Earth Object. But approximately 7000 years ago it had a close encounter with Earth that kicked it into a new orbit. It now occupies a

these stars may be at different stages in the cooling and sorting process. Overall, the team believes that such stars are very unusual. "There are likely to be a few more in our galaxy, but they may well be too faint to be seen," he said. "We are now on the lookout for more zirconium stars, with bigger telescopes."

www.news.nationalgeographic.com

will only remain a Venusian quasisatellite for another 500 So getting back to the story, Hicks and his team used the recent close apparition of 2002 VE68 to conduct measurements over the course of three nights in November. From the colour data they obtained they determined that 2002 VE68 is an X type asteroid. This is a group of asteroids with very similar spectra that could potentially have a variety of compositions. They were able to determine the approximate size of the asteroid to be 200 meters in diameter, based on its absolute magnitude, and they determined a spin rate of 13.5 hours. The amplitude of the fluctuation on the light curve of 2002 VE68 could imply hat it is actually a contact binary, two clumps of asteroidal material orbiting a centre of mass in contact with each other.

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Midlands Astronomy Club Magazine

Tips for using your first Telescope

objects will appear dimmer than you might expect, and you will not see colour in anything but the planets and brighter stars. Don’t be disappointed by this, but instead appreciate what you can see with a simple backyard telescope peering into the limitless depths of the heavens. Know also that the more you observe, the more you will see, as you train your eyes and brain to effectively pick out details in the eyepiece. Over a period of just a few weeks you will begin to see more and more when you use your telescope.

Did you get a telescope as a gift over the holidays? Do you have a telescope, maybe sitting in a closet somewhere, but are not sure how best to use it? In this article, we’re going to talk about how to use telescopes and what there is to look at. First, let’s talk a little bit about how telescopes work. The primary function of any telescope is to gather as much light as possible from the heavens above. More light means brighter images and more clarity. To do this, astronomers build telescopes with the biggest lens or mirror they can. This is why professional observatory telescopes are so physically huge. What about magnification? Isn’t that important? Well, actually, magnification is not a factor when choosing a telescope. The reason is that, by swapping out the interchangeable eyepieces, any telescope can be made to work at any magnification – at least in theory. The problem is, if you have a small telescope, the image will be dim to begin with, and spreading out the light with high magnification will just make things look blurry. In addition, no matter how big a telescope you have, the Earth’s atmosphere wavers constantly, which limits how much you can magnify. For an amateur telescope in the average backyard on an average night, you’ll be lucky to be able to use 300 power before things get ugly. You’ll use that

mostly on the planets, too, because the majority of objects we tend to look at – nebulae, star clusters and other galaxies – are too big to fit in the field of view at that magnification. You’ll find that most of the time you are using somewhere between 40 and 150 power. Let’s take stock of what you have. Telescopes come in many different makes and models, but all of them have some common features. The structure which houses the optics is called the optical tube assembly, also known as the OTA or just referred to as the “tube.” This is what gathers all the starlight and brings it to a focus, using lenses or mirrors depending on the design. The contraption that holds the tube steady and allows you to point it around the sky is known as the mount. Many mounts incorporate a tripod with a head that allows motion, which may or may not be motorised. Some mounts are essentially wooden cradles that hold the tube like a cannon, and allow the user to push it around and aim it in a very simple way.

Above: The path an image takes in a typical reflecting telescope.

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month. www.stellarium.org is a place where you can download a free computer program that shows the night sky for any time from any place on Earth. You can also find monthly astronomy magazines at your local newsstand or library to keep up with the ever-changing night sky.

Above: With a little guidance, you can pick a high-quality telescope that can last a lifetime. S&T: Craig Michael Utter The finder is used to help you to point your telescope to objects in the night sky. Most telescopes c om e w ith e ithe r a li tt le mini-telescope or a non-magnifying red-dot device as a finder. Your telescope will come with one or more eyepieces. Eyepieces take the fixed image formed inside of the telescope tube and magnify it so it can be seen with your eye – this is why changing the eyepiece changes the working magnification of your telescope. Plan your observing session Before you go outside and set up your telescope, you need to know what you going to look at. Aimlessly pointing the telescope in random directions gets old quick for most people. The Moon is an excellent target, as are the brighter planets. In early January 2009, the Moon and the planet Venus are the brightest two objects in the south western sky. You will see lots of craters, mountains and other detail on the Moon through your

telescope. Venus, on the other hand, is shrouded in thick white clouds all the time. It does, however, go through phases just like our Moon – in fact, this is one of the first observations Galileo made 400 years ago to prove the Earth was not the centre of the universe. Later on in the year, Saturn with its rings and Jupiter with its moons and cloud bands will become visible in the evening sky. Other objects available in January 2009 include the Orion nebula and the Pleiades star cluster. There are actually thousands of such “deep-sky” objects within reach of a backyard telescope on any clear night. Which begs the question – how do you know what’s out there? There are two fantastic and free online resources available to amateur astronomers, showing you what’s up and where to look. www.skymaps.com publishes free monthly star charts complete with a list of cool objects to see that

Set up your telescope First, be sure to take it outside. Pointing the telescope through a window from inside the house will never yield a decent image – the glass in the window is nowhere close to optical quality and will distort the image terribly. Likewise, opening the window and sticking the telescope out will cause massive turbulence in the air around the telescope, and again, the image will be unrecognisable. Before using your telescope, you also want to make sure your finder is aligned with your main tube. It’s easiest to do this during the daytime. I suggest sighting in on a distant utility pole or streetlight with the main telescope, and then adjusting the finder to match. It’s important to let your telescope cool down so it’s the same temperature as the outside air. The optics in your telescope are remarkably precise – accurate to within a few millionths of a centimetre of theoretical perfection. If the telescope is warmer than the outside air, the optics will be physically distorted and the images will look blurry and bloated. This is why even professional observatory domes are completely unheated. It takes the average backyard telescope between 20 and 30 minutes to completely reach the same temperature as the outside air. Since you paid good money to

get good optics, don’t spoil the view by trying to observe before your telescope has cooled down completely. This is a common beginner mistake. If you have outdoor lights around your neighbourhood, try to set up in a place where buildings or trees block them as much as possible. You want your telescope to gather starlight, not artificial light, which will wash out the view and make faint celestial objects hard to see or even invisible. If you have access to a place out in the countryside where you can get away from light pollution altogether, so much the better. When searching for objects with your telescope, always start by using your lowest power eyepiece. Why? Because the lower your power, the more sky you are seeing through the eyepiece – you have a larger field of view. Most of the sky is empty, and even with a low-power eyepiece you’ll need to hunt around a little bit to find your celestial quarry. Starting out with high power can make it much more difficult to find that elusive sky object. Even if your telescope has a computer and locates objects for you, you should still start with a lower-power eyepiece – computers locators are good, but not perfect. As you observe, you will find that medium power is best for most objects. The idea is to magnify the image so that it is well-framed in the field of view, but still nice and crisp. Remember, using too much magnification is a primary cause of blurry images. Keep in mind you are looking at objects that are millions of kilometres away in space. Most

There are a few common tweaks amongst backyard telescope users. If you have a tripod, keep in mind that the longer that you extend the legs, the less rigid they will be, so it’s best to extend them as little as possible. You also want to be sure that all bolts are tightened on the tripod to provide maximum rigidity – any wiggle in the tripod will make the image shake in the telescope. Another trick to reducing image shake is to place a weight in the accessory tray of the tripod, which helps to stabilize the telescope and dampen any vibrations. If your telescope comes with an optical finder, some people find it’s helpful to add a non-magnifying device called a “red-dot” finder to help them see where the telescope is pointed in the sky. These are commonly sold online as sights for air rifles, and they cost less than €40. It’s easy to mount them on your telescope with double-sided foam tape. Take a trip to your local astronomy club and ask about thes e red -dot gadgets to see if you might like them.

scope, I recommend sticking with the common and relatively inexpensive Plossl design, available from a wide range of telescope dealers around the world. You don’t need more than 3 or 4 eyepieces in total to give you a good range of powers. This is one of those times where having a friend with a telescope really helps because you can try their eyepieces in your telescope to see what you like and what you don’t. Want to learn more? When you want to learn more about telescopes and stargazing, there is plenty of information available on the Internet. Your local astronomy club has a lot of information and links to all the websites mentioned, and many more. Astronomy clubs are full of friendly people who all love the night sky. Members with their own telescopes enjoy letting other people look through them at club events. Astronomy is one of those things that is much easier to learn in person, so take advantage of any group observing activities your local club offers. I hope this article gave you some insight in the finer points of using your new telescope. Enjoy the wonders of the night sky and have a safe and prosperous International Year of Astronomy 2009!

By Jeff Setzer http://365daysofastronomy.org/

If you want to have a greater range of magnifications available with your telescope, then you will want to investigate buying one or more additional eyepieces. For your first tele-

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