Coastal Breeze News » Southern Skies http://www.coastalbreezenews.com Wed, 23 Apr 2014 14:22:23 +0000 en-US hourly 1 http://wordpress.org/?v=3.9 The Moon Puts on a Good Show http://www.coastalbreezenews.com/2014/04/09/the-moon-puts-on-a-good-show/ http://www.coastalbreezenews.com/2014/04/09/the-moon-puts-on-a-good-show/#comments Wed, 09 Apr 2014 14:37:45 +0000 http://www.coastalbreezenews.com/?p=37728 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

During the early morning hours of Apr. 15, the moon will undergo a total lunar eclipse. Unlike its distant cousin the solar eclipse, a lunar eclipse is perfectly safe to look at as long as you please.

A lunar eclipse happens when the moon passes through earth’s shadow; this only happens at a full moon, and the moon’s orbit crosses the ecliptic (hence the origin of the word “ecliptic”). Another way to express this is to say the centers of the earth, moon and sun temporarily lie in a straight line or nearly so; astronomers speak of this alignment as syzygy – a mostly useless word but great in a Scrabble® game!

The eclipse begins at 12:53 a.m. as the moon moves into the penumbra, a region of partial shadow. This is a truly under-whelming event, so don’t bother to wake up for it. The real action begins at exactly 1:58:19 a.m. when the moon begins to enter the umbra; the region of dense shadow. With a small telescope or steady binoculars you will be able to see earth’s shadow sweep across the lunar surface. Totality comes a little over an hour later at 3:06:46 a.m.

If the earth had no atmosphere the moon would be invisible at this point. However, sunlight is refracted around our planet by our thick layer of air and the moon appears red in color. The color can vary from an almost invisible brick red to a bright red with the lighter shade being most common. Essentially, the moon is illuminated by all the sunrises and sunsets occurring on our home planet. The color is impossible to predict in advance as it is heavily dependent on the worldwide weather. Usually for the very dark brick color something odd must be happening on earth, like a major volcanic eruption. (Think Krakatoa.)

At 4:24:34 a.m. the moon begins to exit the umbra, and is completely free of the umbra at 5:33:02 a.m. Officially, the eclipse is over at 6:37 a.m. when the moon clears the penumbra.

If you get up mid-eclipse the moon may be a bit difficult to locate at first. Fortunately, the moon will lie very close to the bright star Spica and not far from the even brighter Mars.

See you there!

 

Mr. Usher is a Director of the Everglades Astronomical Society, which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.


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Time for Mars http://www.coastalbreezenews.com/2014/03/26/time-for-mars/ http://www.coastalbreezenews.com/2014/03/26/time-for-mars/#comments Thu, 27 Mar 2014 00:31:22 +0000 http://www.coastalbreezenews.com/?p=37573 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

Mars is now the third brightest object in the evening sky. Only Jupiter and the star Sirius beat it out. Reddish Mars is located near the blue white star Spica, and together the two make an interesting color contrast; also nearby is the bright star Arcturus – an orange giant.

Mars is nearing opposition, which it will reach on April 8. When any outer planet is located 180 degrees from the Sun it is said to be at opposition (that is it’s opposite the Sun). The importance for stargazers is that the planet rises at the same time the Sun sets and is visible all night long. Also, opposition is the time the outer planet is nearest to Earth and appears largest and brightest.

In the case of Mars, not all oppositions are created equal; the planet has a rather elliptical orbit and some oppositions are simply better than others as the distance from Earth can vary quite a bit. This particular one is perhaps about average or a bit less. The closest oppositions come in intervals of 15 or 17 years and the best ones always occur in the summertime. You may remember the best opposition of recent times was in August of 2003 when Mars got a considerable amount of press. That particular opposition also spawned a hoax e-mail which annually appears every August promising that Mars will look as large as the Moon. This is flatly impossible.

Although the best oppositions are widely spaced, Mars does return to opposition every 780 days on average – a time span known as the synodic period. Strictly speaking the synodic period is the time it takes any three bodies (typically Earth, Sun and a planet) to return to the same relative positions. Every planet in the Solar System (and the Moon) have their own characteristic synodic period: the Moon 29.5 days; Jupiter 13 months; and Saturn 54 weeks, for example. Please note the synodic period is not the same as an orbital period and is actually a combination of Earth’s and a planet’s motion around the Sun.

On March 22 at Collier-Seminole State Park is a Star Gazing Party open to the general public. Several Everglades Astronomical Society club members and I will be there with telescopes and a park ranger from Big Cypress will give an interpretive presentation. I have heard his presentation before and he does put on a good show! Activities begin at 8 PM. Admission is $4 per car. In case of poor weather we will try again on March 23.

 

See you there!

 

Mr. Usher is a Director of the Everglades Astronomical Society, which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.


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Moon over Marco http://www.coastalbreezenews.com/2014/03/11/moon-over-marco/ http://www.coastalbreezenews.com/2014/03/11/moon-over-marco/#comments Wed, 12 Mar 2014 00:41:32 +0000 http://www.coastalbreezenews.com/?p=37118 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

We do not often talk about the Moon in this column as it usually wipes the stars from the sky when it is present – particularly when it is nearly full. However the Moon is an interesting object in its own right and provides endless hours of entertainment for small telescope owners. In fact it is about the only heavenly object a department store telescope provides a decent view of.

It is shocking that so many misconceptions about our Moon exist; a small but significant percentage of people do not know that the Moon is plainly visible during the day nor that during some nights it is invisible. This is a consequence of its orbit around the Earth; naturally it must spend half of the time on the daylight side of our planet. Another misconception is that there is a “dark” side of the Moon. All parts of the Moon receive their fair share of solar illumination; at any given moment exactly half of the Moon is lit regardless of what phase we see down here on Earth. There is a “far side” of the Moon that we can never see from our vantage point since the Moon always keeps one side facing us, but it has been well mapped by space probes.

A moment ago it was stated the Moon orbits around the Earth; technically speaking this is not exactly true; what happens is the both the Earth and Moon revolve around their common center of gravity. While the Moon moves in a large orbit some 238,000 miles in radius, the Earth moves in a tiny circle only 3,000 miles in radius once every 28 days.

What is even stranger, and a lot harder to visualize, is the Moon does not “go around” the Earth in a traditional manner. From the point of view of someone standing on the Sun all satellites orbit their planets from west to east say, and at some point reverse their direction and complete the circle around the planet from east to west – fairly logical when you sit and think about it for a moment. All satellites except the Moon that is. The Moon never reverses direction! In fact it behaves much as a planet does; from the point of view of someone on the Sun the Moon circles the Sun(!) but in a series of twelve shallow waves plus the beginning of a thirteenth wave each year. (The waves are caused by the presence of the Earth).

If you do not understand all this, do not feel badly, it took humans at least five thousand years to work this out. We will return to the Moon in about two months; it’s scheduled to put on a good show during the early morning hours of April 15th.

See you next time!

 

Mr. Usher is a Director of the Everglades Astronomical Society, which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.

 


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The Zenith http://www.coastalbreezenews.com/2014/02/21/the-zenith/ http://www.coastalbreezenews.com/2014/02/21/the-zenith/#comments Fri, 21 Feb 2014 19:36:32 +0000 http://www.coastalbreezenews.com/?p=36739 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

Every now and then instead of facing a particular point of compass, it’s fun to look straight up — technically called the zenith. Looking up at the zenith has a couple of advantages over other directions: the sky becomes darker, and there is less atmosphere to absorb light so the stars tend to be brighter. The major difficulty is the human body is not well designed to spend an extended period of time staring straight up. Soon your neck starts hurting, and if you move suddenly, you could get dizzy and trip over something. It’s even worse if you use binoculars. Fortunately, a simple solution is close at hand; reclining chairs used around pools are the perfect stargazing accessory here.

Tonight, too-bright-to-miss Jupiter dominates the zenith and indeed the entire sky. It’s the only planet in the sky at the moment although Mars pops up in the East about 10 PM with Saturn following shortly after midnight. Now is the perfect time to whip out your trusty binoculars, and see Jupiter’s four bright satellites. Ranging from just slightly smaller than our own Moon to larger than the planet Mercury, the Galilean satellites are easy to spot with just a small pair of firmly-held binoculars. Indeed, all would be bright enough to see with the naked eye were it not for the overwhelming glare of Jupiter. Occasionally, there are reports of very rare people who can spot one (probably Ganymede) without optical aid.

Jupiter is within the borders of Gemini, the twins where the matching pair of Castor and Pollux form the heads of the stick-figure twins. Pollux is just a bit more luminous than Castor, but reports from ancient times indicate that Castor was the brighter star. It is uncertain if there was a mistake made or if there really has been a change. Several other changes in the sky might have occurred in the last few millennia. For example, the nearby (but not on tonight’s chart) Pleiades are almost universally known as the “seven sisters,” but only six stars are plainly visible to the unaided eye.

Now might be a good time to try and pick out the ridiculously faint constellation of Cancer, the crab. The brightest star in this constellation is only magnitude 3.5, while the Praesepe star cluster within it reaches 3.1. Without a doubt no constellation would have been placed here in ancient times were it not for the fact Cancer occupies a position along the ecliptic — the apparent path the Sun takes during the course of a year. The ecliptic was important to the ancients for several reasons; they must have believed every spot along it deserves it’s own constellation if for no other reason than to provide a convenient marker.

 

See you next time!

Mr. Usher is a Director of the Everglades Astronomical Society, which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.


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The Love Planet http://www.coastalbreezenews.com/2014/02/07/the-love-planet/ http://www.coastalbreezenews.com/2014/02/07/the-love-planet/#comments Sat, 08 Feb 2014 00:12:53 +0000 http://www.coastalbreezenews.com/?p=36387 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

Now that Valentine’s Day is upon us, it might be a good time to check out Venus, the namesake of the Goddess of Love. It might be mentioned in passing that Venus, the mythological being, was not exactly the goddess of love, but was solely the goddess of erotic love — not quite the same thing. Venus the planet, while beautiful to observe, is actually a fairly good approximation of Hell, with its 900 degree surface temperature, sulfurous smell and crushing air pressure. All this is due to the enormous quantities of carbon dioxide present in its atmosphere. Earth has roughly the same amount of carbon as Venus, but here it’s locked up in rocks, such as limestone, and plants.

Those of you that have been following the heavens will have noticed that Venus has vanished from the evening sky; it has crossed between us and the Sun, and has emerged into the morning sky where it will remain until September. The accompanying chart is for 6AM Valentine’s Day. This presents an opportunity to see Venus in broad daylight. Simply keep an eye on Venus as the Sun rises — a glance every minute or so will suffice.

Last time, we talked about the rich area of the sky about Orion. Now, Venus is near the only area of the sky that surpasses the great hunter, the Sagittarius, or Scorpius region. On the chart this morning, we have only the tail of Scorpius but the whole constellation of Sagittarius. This constellation is almost literally stuffed with interesting binocular objects. In fact, there are more Messier objects here than any other constellation. Sweep the entire area very slowly with your binoculars.

You might think it odd to be talking about summer constellations here in mid-winter, but in fact your favorite constellation is visible 10 or 11 months a year. It is just a question of when. So-called summer and winter constellations are classed according to their visibility during early evening hours; the earth continues to rotate as we sleep bringing additional constellations into view. Thus, by early morning, out-of-season constellations are clearly in view. Only the 10- or 15-degree wide band centered on the Sun is blotted out on any given night.

See you next time!

 

Mr. Usher is a Director of the Everglades Astronomical Society, which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.

 


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Can You See the “G”? http://www.coastalbreezenews.com/2014/01/29/can-you-see-the-g-2/ http://www.coastalbreezenews.com/2014/01/29/can-you-see-the-g-2/#comments Wed, 29 Jan 2014 14:16:11 +0000 http://www.coastalbreezenews.com/?p=35990 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

Here on Marco, the constellation Orion rides much higher in the sky than our northern visitors are used to. This allows the bright stars to really shine out with their full brilliance. Tonight, the chart depicts a close-up of this fascinating area of the sky.

The first thing a casual stargazer should notice is how the bright stars in this constellation are all very blue — with one huge exception, Betelgeuse. This star, in the upper left of the constellation, is a red supergiant; despite the name, it looks rather closer to a deep orange color. Hubble photographs show a disk that is red with a yellow spot near the center. There is considerable debate in scientific circles as to exactly what causes this. Betelgeuse is one of two stars that are both near enough and large enough to show a visible disk but only to space-based Hubble.

If you own a pair of binoculars, the area in and around Orion is something of a paradise. In particular, notice the Great Orion Nebula, so bright that it is even visible to the naked eye in suburban skies. At a dark sky viewing sight, the nebula looks like a fat fuzzy star. With binoculars, the nebula is clearly visible as a glowi

ng cloud. Interestingly it glows for the same reason a fluorescent light glows. Stars in its heart emit copious quantities of UV light that causes the oxygen in the nebula to emit a greenish glow. Some observers claim to spot the green color with binoculars although that is hard to believe. In a large amateur telescope, the color is easily evident.

While you have the binoculars out, see if you can locate the nearby M78 nebula and the brighter Cone Nebula. The second most well-known nebula in the area is the famous Horsehead Nebula, just a little south of Alnitak. Invisible to binoculars and almost all telescopes, it is primarily a target for photography. Probably no general interest book on Astronomy is missing a photograph of the Horsehead.

Although this week’s chart does not clearly show it, Orion can be used as a pointer towards other constellations, a little like the Big Dipper. An imaginary line drawn from Rigel through Betelgeuse points in the general direction of Gemini. Drawn the opposite direction, the line points to the center of Eridanus. A line extended downwards from the belt stars indicates the direction of Sirius, and extended upwards indicates Aldebaran. Drop due south, and you will reach Lepus the hare. Orion’s shield faces Taurus the bull.

See you next time!

 

Mr. Usher is a Director of the Everglades Astronomical Society, which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.


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Can You See the “G”? http://www.coastalbreezenews.com/2014/01/16/can-you-see-the-g/ http://www.coastalbreezenews.com/2014/01/16/can-you-see-the-g/#comments Fri, 17 Jan 2014 02:44:50 +0000 http://www.coastalbreezenews.com/?p=35762 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

Tonight, the chart is showing just about everyone’s favorite portion of the sky, or it would be if it were not high in the sky on winter evenings when the normal temperature discourages viewing. This is not a problem on Marco Island, however; and this area contains something for every stargazer whether naked eye, binocular or telescope user.

First, notice the enormous “G” shape formed by the eight first magnitude stars: Aldebaran, Capella, Castor, Pollux, Procyon, Sirius, Rigel and Betelgeuse. Nowhere else in the sky will you find such a concentration of bright stars. This is not a total coincidence as this area lies both in or near the Milky Way, and the Orion Spur — one of our galaxies minor spiral arms.

Giant Jupiter is a temporary resident of the constellation Gemini. It simply cannot be missed even on bright moonlit nights. Only Venus and the Moon are brighter residents of the night sky. Binocular users can be entertained by the nightly dance of Jupiter’s four large satellites. A much more difficult object is the Crab Nebula. If you look, choose a moonless night, and use a rock steady support for your binoculars. Search for the faintest possible smudge above the tip of Taurus’ horn and you’ll find it. Long-time exposures actually reveal the Crab Nebula as one of the more spectacular objects in the sky.

There are any number of star clusters in this region tonight; a sweep with your binoculars along the Milky Way will reveal many. There is one star cluster on the chart tonight easily visible to the naked eye — the Hyades. The brightest members of the cluster forms the V-shaped head of Taurus the bull. Only 150 light years away, the Hyades is the closest cluster to Earth, accounting for its spread out look. The bright orange star Aldebaran is not a member, however, being less than half as far away but lying on the same line of sight by chance. The Hyades appear to be very closely related to another star cluster, the Praesepe cluster in Cancer — so closely in fact they appear to have shared a common origin. There is no relationship to the visually nearby Pleiades however.

 

See you next time!

 

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7PM in the Norris Center, Cambier Park, Naples.


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Jupiter Rises in the East http://www.coastalbreezenews.com/2014/01/01/jupiter-rises-in-the-east/ http://www.coastalbreezenews.com/2014/01/01/jupiter-rises-in-the-east/#comments Wed, 01 Jan 2014 18:58:04 +0000 http://www.coastalbreezenews.com/?p=35439 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

Tonight, mighty Orion has heaved himself above the horizon, but first, let’s look at the heavenly river Eridanus. Composed of mostly dim stars, the Eridanus is supposed to represent the Nile or the Euphrates. It arises near the foot of Orion and winds thru many twists and turns into the deep southern sky, terminating at the blue star Achernar. This star is one of the very brightest in the sky but is dimed by the murk above the horizon.

Achernar is never visible further north than Macon, and in fact, is mostly impossible to see north of the Florida border. Even here, it only briefly pops above the horizon in late fall and early winter. Chances are you will not see it unless you have an unobstructed view of the southern horizon. Achernar is also one of the stranger stars in the sky. It rotates so fast that it is highly flattened. It’s equatorial diameter is 50 percent greater than it’s polar diameter; in other words, it’s even more oval than an egg.

Orion was mentioned last column, but we can always mention it again. Careful observers can spend hours staring at it’s wonders both visually and with binoculars. The stars in Orion are mostly very blue in color, particularly Rigel, the brightest star in the constellation. The lone exception is Betelgeuse, one of two red supergiant stars visible to the naked eye. The name is commonly pronounced “Beetle Juice” in the U.S., and is about as close as Americans can come to the original Arabic pronunciation.

Betelgeuse is rapidly nearing the end of it’s life and will explode into a supernova sometime in the future. Perhaps a million years from now or maybe tomorrow, no one knows. A detonating supernova too close to Earth would be uncomfortable, but at 427 light years, this one should be safe enough — and we will have an excellent view. It will easily be visible in the daytime and will compete with the full moon at night.

No mention of Orion is complete without mention of the Great Orion Nebula. To the naked eye, it appears as a fuzzy star south of Orion’s belt. It’s actually a giant cloud of gas and dust that acts as a stellar nursery, and is one of the finest visible in our galaxy. Perhaps 1,000 stars lie hidden inside the nebula; only a few are visible with binoculars. Four stars at the heart of the nebula give off copious UV radiation which causes the nebula to glow with a greenish light to the eye and reddish to old fashioned film cameras. Inside the nebula stars seem to be a little too crowded to have stable orbits. Indeed, several stars scattered across our sky are thought to have been ejected from the nebula in the past.

See you next time!

 

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7PM in the Norris Center, Cambier Park, Naples.


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Jupiter Rises in the East Comet http://www.coastalbreezenews.com/2013/12/23/jupiter-rises-in-the-east-comet/ http://www.coastalbreezenews.com/2013/12/23/jupiter-rises-in-the-east-comet/#comments Mon, 23 Dec 2013 14:44:25 +0000 http://www.coastalbreezenews.com/?p=35535 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

Comet ISON was totally roasted on Thanksgiving day during its suicide dive into the close proximity of the Sun. Apparently nothing is left of the comet except perhaps a few rocks. At less than one solar diameter distance, the comet failed to endure temperatures hot enough to melt iron. Needless to say, my careful instructions on how to view the comet during December turned out to be useless.

In the form of a consolation prize, we now have Jupiter visible again during the early evening hours this winter. It can not be missed in the eastern sky tonight as Jupiter is far brighter than any star in the sky. Only the Moon and Venus are brighter. There is no mistaking the Moon, and Venus is clear over on the other side of the sky.

Check out Jupiter in your trusty binoculars, and you can catch the eternal dance of it’s four giant satellites — each as large or larger than our own Moon. Distance shrinks them down to pinpoints of course, but they are still easy to spot with binoculars. The real trick is holding the binoculars steady enough to get a good look. Try propping your arms on a car rooftop; there are also little attachments you can buy to mount binoculars to a camera tripod. At the time given in the caption, Callisto is just above Jupiter. Io is above Jupiter also, but may be too close to the body of the planet to be easily seen. Ganymede is directly between Jupiter and us, and is invisible in the glare of the planet. Under certain circumstances, a powerful amateur telescope can spot its shadow at such times. Europa is below Jupiter.

Naked eye observers will be drawn to the mighty constellation of Orion. The striking pattern of a bright rectangle of stars together with the three belt stars is visible over the entire inhabited surface of the Earth. Mostly invisible to the naked eye is the enormous gas cloud that these stars formed from. In one small area, though, there is a fuzzy spot easily visible even in suburban Marco. This is known as the Great Nebula in Orion, and is one of just two star-forming regions in our galaxy that can be seen with the naked eye. The other is in the far southern constellation of Carina.

 

See you next time!

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7PM in the Norris Center, Cambier Park, Naples.


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Comet ISON Survived? http://www.coastalbreezenews.com/2013/12/04/comet-ison-survived/ http://www.coastalbreezenews.com/2013/12/04/comet-ison-survived/#comments Wed, 04 Dec 2013 18:18:19 +0000 http://www.coastalbreezenews.com/?p=34974 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

At the time of this writing, the ultimate fate of Comet ISON was still in doubt. On Thanksgiving day the comet reaches its closest point to the Sun, (called perihelion by astronomers) and is less than one million miles from the solar surface. At that distance the heat is enough to melt solid iron! On the other hand, the comet is a big chunk of loosely packed ice and dust which is a pretty good insulator; it may well pull through. The odds are around 50-50.

Until recently the comet was fizzling out, a not uncommon thing for new comets making their first trip to the inner Solar System, until Thursday November 14th when the comet suddenly became visible to the naked eye. A blast of dust or water vapor emerged from the nucleus and caused the comet to jump two magnitudes in brightness. With any kind of luck the show should continue after the comet rounds the Sun.

During the first week of December the comet will be low in the sky in the morning twilight – which may make the comet hard to see without binoculars. Over the next three weeks the comet will dart quickly away to the northeast rising higher in the sky as it does so. On December 26th the comet will reach it’s closest point to Earth when it will be near Draco’s back and visible for much of the night. On January 7th it will only be a couple of degrees away from Polaris the North Star and visible all night long; although by that date it will only be seen through binoculars.

As the comet pulls away from the Sun, (if it pulls away), it will rapidly dim; on the other hand it will be approaching Earth during this point in its orbit and that will partly offset the dimming. It is likely to be visible to the naked eye throughout the month of December in a dark sky.

An interesting bit of comet trivia is that a comet’s tail always points away from the Sun, regardless of the actual motion of the comet. This is caused by the pressure of the solar wind and light. Many comets, including ISON, have two tails; one is dust, the other is ionized gas. The two materials move in slightly different directions under the Sun’s influence. Comets normally appear white to the eye, although in a camera’s time exposure photograph the dust tail is often blue. Comet ISON however, is a rather interesting green color! (But only in photographs…)

 

See you next time!

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7PM in the Norris Center, Cambier Park, Naples.


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Should You Buy a Telescope? http://www.coastalbreezenews.com/2013/11/20/should-you-buy-a-telescope-3/ http://www.coastalbreezenews.com/2013/11/20/should-you-buy-a-telescope-3/#comments Wed, 20 Nov 2013 15:13:52 +0000 http://www.coastalbreezenews.com/?p=34723 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

This morning, perhaps as you are walking the dog, look to the east and you have a chance to spot Comet ISON. It’s going to be quite low to the horizon and will be of uncertain brightness. Mercury and Saturn should be visible and they should provide handy reference points. The comet is moving fast, passing just below Spica on the 18th, and drops below Mercury by the 23rd. Both moonlight and twilight will interfere with the comets visibility.

This is the time of year when everyone asks me “what kind of telescope should I buy for my spouse/child/grandchild?” The quick answer is none; take the money set aside for a telescope and purchase binoculars instead. There are two reasons for this: first, the expectations of what you will going to see through the telescope far exceed the reality, secondly, a telescope is a precision engineered optical device and such devices are not inexpensive.

Still, with Christmastime fast approaching and money burning holes in pockets, people still insist on buying telescopes. I’ll throw out a few prices so you can help orient yourself and see what is a fair deal versus a rip-off. The prices given are for stripped down basic models with decent optics. Specifically, models called Newtonian reflectors with Dobsonian mounts (NOT tripods), minimum of accessories and NO electronics. Dollar for dollar they are the best buys today. Add $200 and up if you want electronics. Please note all telescopes come with a very steep learning curve! In my lifetime, I have never seen a pre-teen have the patience required to master a telescope although they really do enjoy viewing with one.

Quality telescopes are sold by aperture – the diameter of the mirror (or lens); all sizes given below are in reference to the aperture. The length of the telescope is 4 to 8 times larger than the aperture, plus the mount.

• 6 inch (150mm) – the smallest size considered useful by amateurs, about $300. Easily portable, an excellent size for young teens.

• 8 inch (200mm) – possibly the most common size used by amateurs, about $350. Very portable, widely owned by amateurs of both genders and all ages.

• 10 inch (250mm) – recently became the average size used by amateurs, about $575. Starting to push the boundary of what can be transported by a standard sized car. They weigh about 50 pounds, and are rather bulky.

• 12 inch (300mm) – about $1100. You need a pickup truck or SUV here for transportation. They weigh about 80 pounds and are rather bulky.

In case anyone is interested, I own a 20 inch – it tops the scale at 197 pounds!!

For additional useful information and a list of manufacturers, please drop me an e-mail at usher34105@earthlink.net.

 

See you next time!

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7PM in the Norris Center, Cambier Park, Naples.


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Goodbye to Summer http://www.coastalbreezenews.com/2013/11/08/goodbye-to-summer/ http://www.coastalbreezenews.com/2013/11/08/goodbye-to-summer/#comments Fri, 08 Nov 2013 15:46:56 +0000 http://www.coastalbreezenews.com/?p=34478 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

The rainy season is finally over! The unrelenting clouds made it very difficult to do any stargazing this summer; but we can finally see stars at a reasonable hour so we are rolling back the clock on the charts to 9PM.

Tonight is one of the last chances to see a few summer – season stars before they drop into the Gulf of Mexico. Front and center is the not particularly well named Summer Triangle, (this being the middle of Autumn), consisting of the bright stars, Vega, Altair and Vega. Vega and Altair are close neighbors of our Sun being only 25 and 17 light years away respectively. Deneb is the outlier, being 2600 light years from us although the exact distance is rather uncertain.

How do we measure distances to the stars? The traditional method is to use parallax in a manor similar to surveyors. A photograph of a star is taken in January, for example, and another is taken in July when the Earth is on the opposite side of the sun. The star, if it’s close enough, shows a shift in position when compared against background stars. This shift, when trigonometry is used, yields the distance to the star. Such shifts are extraordinarily tiny and distances over a few hundred light years are very uncertain as a result. Fortunately, other methods exist but are thought to be not quite as accurate.

The Summer triangle encloses a section of the Milky Way that is rich with star clusters; feel free to scan the area with your binoculars. Your naked eye however will notice a dark gash through the area, marring the soft whiteness of the Milky Way. This is known as the Great Rift and consists of a large mass of gas and dust blocking the light of the stars behind it. A few stars do glimmer in this area, however these are stars between us and the Great Rift. The nearby Moon probably will wash out this area of the sky; it would be better to wait a week or ten days when the Moon will no longer be in the evening sky.

Comet ISON continues its nose dive into the inner Solar System. Depending on how it brightens I’ll either give an update next column or run the “buying a telescope” guide in time for Black Friday. Either way you will probably be getting up early that morning!

 

See you next time!

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7:00PM in the Norris Center, Cambier Park, Naples.


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The Surprise Planet http://www.coastalbreezenews.com/2013/10/27/the-surprise-planet/ http://www.coastalbreezenews.com/2013/10/27/the-surprise-planet/#comments Sun, 27 Oct 2013 21:16:35 +0000 http://www.coastalbreezenews.com/?p=34226 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

John Flamsteed was born in 1646 in England and was the first Astronomer Royal. Flamsteed’s particular astronomical passion was the careful mapping of all the naked eye visible stars. Flamsteed had this idea that the stars were forever fixed in their relative positions and his life’s work would be the final say on the matter – he considered this his own path to immortality. If you recall Bayer’s catalog used Greek letter designations for the stars and was thus limited to just 24 stars per constellation. Flamsteed’s method was to simply apply a number to each visible star in a given constellation according to increasing right ascension. Even today we can refer to a star as 61 Cygni for example. But simple numbering was no longer accurate enough; each star had to be carefully plotted in its own spot on the celestial sphere to make easier the plotting of planetary orbits, and the identification of variable stars and novas. For this purpose Flamsteed used a small telescope, adequate for his day but would be considered poor quality now.

In 1690, Flamsteed was working his way through the constellation Taurus and he plotted an unremarkable star called 34 Tauri. A few days later he returned to the same spot and was chagrined to find he had made a mistake in plotting its position. This time he took extreme care in plotting the exact position of 34 Tauri – and never looked at it again. But Flamsteed made no mistake in position! The star 34 Tauri had moved; nowadays we call it the planet Uranus.

Flamsteed spotted the planet Uranus almost a century before anyone else and missed out making one of the greatest astronomical finds in history – all because of his preconceived notion of fixed stars. To be fair, everyone in his day thought the stars positions were fixed so he can’t be entirely faulted; but even today great discoveries are made by noticing details everyone else missed.

Flamsteed just worked with stars visible to the naked eye; his telescope was just an aid to plotting and indeed Uranus is visible without optical aid – barely. Tonight it is very high in the sky in the constellation Pisces, a little to the south of the Great Square of Pegasus. At magnitude 5.73 it is at the edge of naked eye visibility, but it is a cinch in binoculars. At the moment it is in an area of the sky devoid of bright stars; if you can point the binoculars at the approximate spot, Uranus will be the brightest star in the field.

 

See you next time!

 

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7:00PM in the Norris Center, Cambier Park, Naples.


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Comet ISON Update http://www.coastalbreezenews.com/2013/10/11/comet-ison-update/ http://www.coastalbreezenews.com/2013/10/11/comet-ison-update/#comments Fri, 11 Oct 2013 13:36:48 +0000 http://www.coastalbreezenews.com/?p=34034 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

On October 1 Comet ISON breezed by Mars at a safe distance while every space probe on or around the planet with a working camera tried to take its picture. Sometime this month the comet is expected to brighten enough to be come visible to the naked eye, although what its ultimate brightness will be is still a matter of considerable debate. Comet ISON seems to be fizzling out, a not uncommon occurrence for comets making their first trip around the Sun. Scientists have backed off on their claims about the comet becoming as bright as the Moon. In any event ISON must first survive its close brush with the Sun on November 28th; the comet is expected to pass less than million miles from our personal star – total destruction is possible. If the comet squeaks by the Sun then it passes our planet on December 26th at a safe distance of 40 million miles.

In the chart this week Comet ISON still appears close to Mars, but in actuality it’s about 20 million miles away from the Red Planet. Mars is easy to find, being quite close to Regulus. Mars is probably much dimmer than you remember, but it’s close to 200 million miles away! Comet ISON is more of a problem – it may, or may not be visible in binoculars. Look for a fuzzy spot to the left of Mars; probably no tail will be visible.

While Leo is commonly considered a spring constellation, that is a conception based on when casual stargazers usually view it. In reality of course one can view their favorite constellation or planet almost anytime of year – if you are willing to get up early enough. Leo is visible anytime the Sun is not actually passing through it.

See you next time!

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday of the month Sept. thru June at 7:00PM in the Norris Center, Cambier Park, Naples.


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Stargazing in Style http://www.coastalbreezenews.com/2013/09/27/stargazing-in-style/ http://www.coastalbreezenews.com/2013/09/27/stargazing-in-style/#comments Fri, 27 Sep 2013 12:48:26 +0000 http://www.coastalbreezenews.com/?p=33756 SOUTHERN SKIES
By Mike P. Usher
usher34105@earthlink.net

It’s been sometime since we discussed the equipment needed for stargazing. You really need very little, but there are some aids which are very useful. First, you need a dim red flashlight to read any charts you bring outside with you. A red light will leave your eyes’ dark adaptation relatively unscathed; just a few seconds of white light will require your eyes to spend up to 30 minutes to regain their sensitivity. A penlight with a red LED is ideal, several layers of red cellophane over the lens of a regular flashlight works about as well. In a pinch, red paint on the flashlight lens works too!

Next, purchasing a planisphere is very helpful; virtually all serious stargazers use them. A planisphere is simply a map of the sky that rotates around a small rivet. Around the edge of the map are two printed circles – one showing the date and another the time. To use the planisphere, rotate the map until the current date and time line up. When purchasing a planisphere it is vitally important that it is drawn to match the latitude you are trying to use it in. The ones purchased locally in bookstores, for example, are invariably drawn for 40 degrees latitude while we are at 26 degrees. The 14 degree difference makes a huge difference in what is visible in the sky. Proper ones are available on the internet, and while you are at it, pick up the LED flashlight as well.

The ubiquitous smartphones have apps available that do about the same thing as a planisphere and some of these apps are even free. They do a pretty good job, but almost no serious stargazers use them routinely. When I have used them I find the screens are just too darn bright even when they are in “night mode” and only a small patch of sky is visible.

When looking for objects not easily visible to the naked eye, I use a laptop computer running a program called Stellarium. Many other programs are available which do the same thing and may have more features, but the price for Stellarium can’t be beat – it’s free! It can be downloaded at www.stellarium.org. The program is a great deal more flexible than anything found on a smartphone; the laptop screen is still too bright on night mode, but red cellophane fixes that.

See you next time!

 

Mr. Usher is President of the Everglades Astronomical Society which meets the second Tuesday each month at 7 PM in the Norris Center, Cambier Park, Naples.


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