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Downloading the PDF. To download your free copy of Sky & Telescope's latest Index to Volume, click on one of the following links: Index to Volume You don't have to be a science whiz to be a successful stargazer. You just need three things: curiosity, a clear view of the night sky, and some pointers on how to . Sky & Telescope's January digital issue, available as a convenient PDF download, contains the following feature articles in addition to the monthly.
The amount of observable celestial objects and their visible details will depend on several factors: The size and the optical quality of your telescope, the observing location sky darkness and atmospheric stability and even the observer's experience. Let's start with the instrument: There are two most important parameters in a telescope: The "aperture" and the "optical quality". Aperture is the diameter of an objective lens or a mirror - it defines how much light the telescope gathers and the maximum resolution it can achieve. Optical quality is the ability of the telescope to transmit unaltered image and it can roughly be expressed via telescope's price divided by its aperture I'm referring to an optical tube assembly only and ignoring the mount issue. In this article there are 3 telescope categories, which will be referred to using [orange] tags in illustrations. This can be a cheap mm Newtonian reflector or a mm refractor, with a quite inferior optical quality.
This w ill also prevent tube currents from harm ing the image. If you need to align on the Sun, try to set up in the afternoon just outside the shadow of a building, and then start observing once the shadow has covered the scope.
Alternatively, use a beach um brella to shade the scope after doing the alignment. Determ ine your targets in advance using a planetarium program, a sky app on a handheld device, or the free skychart at skypub. You can focus on the Moon, the edge of a cloud, or a tree or building at least 1, yards or meters distant. Otherwise, you w ill need to fall back on the techniques that you practiced in the dark.
You can get a crude fix on the Sun by m inim izing the shadow that your telescope casts on the ground. I f Venus is visible, it makes an excellent second or third alignm ent point. Once you have Venus in the center of the eyepiece, sync on it to improve pointing accuracy. I use Venus as a trusty anchor to come back to if I lose my way. From Venus you can move on to any of the bright stars in the Sum m er Triangle or W in ter Hexagon, just as you did at night.
W hen going for a star, bear in m ind that. Vanderbei's daylight Jupiter image, also taken with a Questar as shown on the previous page, captured amazing detail on the planet's disk. The key to this exposure was shooting through a hydrogen-alpha filter. Spotting a planet when the Sun is up can give you a unique feeling for our place in the solar system — especially when the Moon is in the scene too.
Use an alm anac or computer to Robert Vanderbei was able to image Messier The Sun never comes near the Big Dipper or Cassiopeia. Start w ith a constellation in the darkest part of the sky.
In addition to your amateur-astronomy brethren. The pinkish artifact toward the right is lens flare. Then locate Venus in binoculars.
Second-magnitude M izar has a 4thm agnitude companion just 14" away. M arch presents ideal geometry for observers at midnorthern latitudes. The ultim ate daytime observing prize is a naked-eye sighting.
Jupiter is surprisingly easy to hold in view im m ediately after sunrise. But if the tree or flagpole is nearby. In any case. A tree can work well.
Once you capture the star. As you locate more stars and planets during the day. Try to visualize how the ecliptic arcs upward from the Sun in the sky.
A n even bigger prize may be available for those in the Southern Hemisphere. A parking lot w ith a flagpole is useful for the next trick. The same technique works for Jupiter. Pushing the Envelope Now that you can locate the brightest stars.
The darkest part of the sky lies opposite the Sun and well above the horizon. I f you wear eyeglasses. He would like to thank the members o f the Astronomical Society o f Harrisburgfor nurturing a lifelong love o f astronomy. W alk around un til you place the flagpole directly below Venus. Specify your telescope make and model when placing your order. The kit includes an innovative dual-rod altitude device that combines a stainless-steel threaded rod with a custom micro-adjustment wheel.
CNC Parts Supply. T he d e scrip tio n s are b ased largely on inform ation supplied by the m a n u fa ctu re rs or d istrib uto rs. VariMax attaches to any T-ring adapter and is extendable up to 1. The mount includes a heavy-duty stainless-steel tripod.
Its 6-inch dovetail saddle plate accepts both Vixen and Losmandy-style dovetail bars. TN Weighing 25 pounds 11 kg. Featuring precision stepper motors. MA Rapid motions in altitude are performed using an extendable rod and locking knob visible at the lower end of the altitude attachment. Chattanooga Millworks.
The center of the map is overhead. Turn the map around so the yellow label for the direction you're facing is at the bottom. The Moon occults Saturn during daylight in easternmost Canada and during dusk in parts of Europe. Above it are the constellations in front of you. Binoculars may show Mercury below the thin crescent Moon very low in the east a half hour before sunrise. The zodiacal light is visible to That's the horizon.
Saturn floats a few degrees to the lower right of the thin crescent Moon low in the westsouthwest a half hour after sunset. Oct 6 minutes before sunrise from dark locations at mid- northern latitudes.
Nov 4 DAWN: The zodiacal light is again visible before sunrise. Oct Look east for a huge. See page EDT Full Oct. Ignore the parts V of the map above horizons you're not facing. Go out within an hour of a time listed to the right. The Moon shines upper right of Jupiter on the 17th and lower right of Jupiter on the 18th. The waxing crescent Moon shines to the right of Mars on the 27th as seen from North America and above Mars on the 28th.
I can see the object readily in my 10x30 image-stabilized binoculars. A prominent orange star. Although some sources list the nebula as bright as magnitude 4. Arguably its most famous and photographed deep-sky treasure is the notoriously difficult North America Nebula.
Cataloged as NGC and Caldwell The most prominent area is the one bordered by the dark Gulf of Mexico. Yet it can. Cygnus is one of the most familiar constellations. But discerning its form — or for that matter. Central America and the Eastern Seaboard are the brightest and easiest sections to make out.
Dark skies are a must. Not only is it visible for much of the year it shows up on 9 of our 12 monthly all-sky charts. Transits occur an hour later on the 1st. Next are the visual magnitude and equatorial diameter. TheSunandplanets are positioned for mid-October.
For other dates. Blue ticks indicate the pole currently tilted toward Earth. Based on the mean Earth-Sun distance. I was treated to a pair of w ild swans staying week after week at the sm all pond near where I live. The woodland paths are dry.
Albireo is moving almost straight toward us — in a few m illion years its proximity w ill make it one of the brightest stars in the night sky. Procyon is probably slightly more distant. But after that night. The Wild Swans at Coole Back in the autumn of I f you reverse the num erals of 61 Cygni. Upon the brimming water among the stones Are nine-and-fifty swans. The two stars are a 3. Among what rushes will they build.
M agnifications as low as 10x can show that this star. Some observers say it is blue. NGC But binoculars and telescopes and keen naked eyes. I first discovered their marvelous secrets in the s. I never saw them again. See what you think! Pairing 61 Cygni w ith 16 Cygni. Under the October twilight the water Mirrors a still sky. Om icron2. As Yeats said.
But now they drift on the still water. I have seen 30 Cygni as delicately green. Its name is Cygnus. W e w ill double up on doubles. A double star in Cygnus perhaps as famous as Albireo is 61 Cygni. Albireo and Omicron Cygni. Telescopes show that 61 Cygni is a beautiful pair of orange stars. Just a few degrees northwest of Deneb is a pair of stars separated by about a degree: M y w ish came true. The trees are in their autumn beauty.
Cygnus is home to the most famous of all strongly colored double stars — Beta Cygni. Am azingly. The yellow components of 16 Cygni shine at magnitude 6. A challenging occultation of Saturn by the 3. A t magnitude 5. The occultation should be somewhat easier for Spain and the British Isles. Dusk this month features Saturn sinking very low in the west-southwest and M ars m aintaining its modest height in the southwest.
Along the way. Uranus is usually too faint to spot through a telescope when near the fu ll Moon. And late in the month M ercury approaches the peak of its best dawn apparition of for Northern Hem isphere observers. See page 50 of the September issue for a finder chart for both planets.
But Mars glides rapidly east through the stars during the month. Bright Jupiter rises after m idnight and is fairly high by dawn. See the June issue. Venus may be visible shortly before sunrise at the beginning of October.
Only the easternmost U. By am azing coincidence. The 3. It shines 2. The kingly planet brightens to magnitude. See page 50 for the lunar eclipse early on the m orning of October 8th and page 52 for the October 23rd eclipse of the Sun. By October 31st it has brightened fourfold. Decem ber but its globe is still only a little larger than its m inim um apparent diameter. Fred Schaaf To see what the sky looks like at any given time and date.
Jupiter clim bs high in the southeast by m orning twilight. The planet soon becomes lost from view in the solar glare. It should become visible to the unaided eye around October 24th. Even so. Back in the evening sky after the solar eclipse. A thicker crescent passes to the right M ars on October 27th and above Mars on the 28th. Venus starts the month rising only V hour before the Sun. The outer planets don't change position enough in a month to notice at this scale. DAWN Mercury goes through inferior conjunction on October 16th and then rapidly ascends into dawn view.
The waning crescent Moon is to the right of Jupiter at dawn on October 17th and below Jupiter. The Moon undergoes a total eclipse w hile passing near or in front of Uranus on October 8th see page Oct 17—20 1 hour before sunrise Moon Oct 17 Dusk. Oct 20—22 Dawn. Easterners w ill find dawn brightening and the Moon sinking low in the west w hile the eclipse is in progress — offering particularly interesting photo opportunities.
The penum bral shading becomes stronger as the m inutes tick off and the Moon moves deeper in. Moreover the Moon. A n hour or so into partial eclipse. We're approaching the second of four total lunar eclipses that come at half-year intervals this year and next: The map. The second stage is partial eclipse. A ll four can be seen from at least parts of North Am erica. The third stage is total eclipse.
W ith a telescope. The one coming on the m orning of Wednesday. October 8th. Although the Sun here is completely hidden. And the rest is already showing an eerie reddish glow. Stages of the Eclipse A total lunar eclipse has five stages.
Totality this tim e lasts 59 minutes. Total eclipse ends 7: On rare occasions the eclipsed Moon does go almost black. Partial eclipse begins 5: W hen all of the Moon escapes the umbra. Penumbra last visible? Because an eclipsed Moon is always full. And then. Partial eclipse ends — 7: For your location. Mid-eclipse 6: Sometimes it turns brown like m ilk chocolate.
Uranus Too! By quite a coincidence the planet Uranus. The first is simply how deeply the Moon goes into the umbra. But if a major volcanic eruption has recently polluted the stratosphere w ith thin global haze.
This means a lunareclipse moonset or moonrise always happens in a bright sky. Total eclipse begins 6: Other times it appears as bright as a fresh penny. I f the air is very clear. This final duskiness slowly fades away. The actual position of the eclipsed Moon on the starry background in Pisces w ill depend slightly on where you are and the stage of the eclipse.
O r you can try pinhole projection. Has the blue become deeper and purer? You may be surprised by how m uch sunlight has to be lost before anything looks different. Nowhere w ill this eclipse of the Sun be total. During a partial eclipse. For most of the East Coast. Another option is to project a sharp image of the Sun onto a piece of paper w ith binoculars or a sm all telescope.
In a telescope Uranus is a tiny disk 3. For precise local times for many cities and towns. The farther north you are. And a Selenelion? Staring at the bright Sun without a safely designed filter can perm anently damage your vision.
Contrast w ith the vivid orange-red Moon may make this color a little more apparent. O r make little holes between the fingers of your two hands laid across each other at right angles. East of that line.
In most of the eastern h a lf of the continent. In San Diego. On the chart.
For more about viewing and photographing the partially eclipsed Sun safely. Identify Uranus by the shape of the triangle it makes w ith those two stars. Meteorologist Joe Rao points out that this eclipse presents an unusual chance to try seeing a selenelion: Pacific Daylight Tim e. In the Am erican and Canadian West. For this event. M aine and the M aritim e provinces miss out altogether. But as the map at right shows. This is possible for three reasons: A n even trickier problem w ill be the bright sky.
Sometimes other planets get all the good stuff! On October 19th. Moonset and sunrise refer to the top edges of the Moon and Sun. It will be low in the southwest at the end of twilight. And atmospheric refraction at the horizon lifts the apparent position of all celestial objects there by 0. This partial eclipse is just a warm-up. The chart shows where to narrow in with your scope.
So bring good optical aid. The daily ticks are at 0: See skypub. Bradley Schaefer. Seen from Earth. Find what time the eclipse will be deepest at your site by interpolating between the red lines. Comet Siding Spring should be about 9th magnitude in mid-October.
Expect this event to make news when the time comes. The various spacecraft on and around Mars will attempt close-up observations. It will miss Mars by just All times are given in Pacific Daylight Time. For most eastern cities. UT dates are at left. An occultation or eclipse begins when the satellite disappears D and ends when it reappears R. E Oct. The first columns give the date and midtime of the event.
I Oct. R R Oct. Slide a paper's edge down to your date and time. R III. E Every day.
D 21 III. Each event is gradual. E E III. D III. Next is the type of event: A transit or shadow passage begins at ingress I and ends at egress E. II Europa. Each gray or black horizontal band is one day.
Interactions between Jupiter and its satellites are listed above. III Ganymede. The central vertical band is Jupiter itself. Identify them using the diagram at left.
Next is the satellite involved: I for Io. October Thus we can periodically see some farside equatorial features not norm ally visible. Due to lunar libration. Librations are not caused by the Moon itself physically tilting and bobbing. Anyone who looks at the Moon regularly notices that features appear to change their positions w ith respect to the limb. Sometimes the eastern shores of M are Crisium nearly touch the lim b as it appears to on October 1st.
Note the extreme difference of perspective between these two images of the flooded crater Endymion center in the far left image. These changes in velocity result in terrestrial observers being able to peek around the lunar east and west limbs by as m uch as 7.
At far left. The Moon rotates at a constant velocity around its polar axis its day is of constant length. On the evening of October 5th. On the 5th the librated lim b lies in shadow and thus is not observable. The Moon Is a Harsh Mistress. The best libration then migrates eastward to the southeast lim b near Lyot two nights later. Because of the interplay of all the different components of libration.
W hen observing the Moon. This means that every tim e you observe the Moon. Wood ne ver consults a libration chart.
You can demonstrate this for yourself: Craters on that lim b appear more in profile than how we usually see them. This month there are no extreme librations visible on the illum inated limb. Sim ilarly. That cycle continues. Although the positive liberated areas reveal Earthward tilted views of those limbs. Because the total libration of the Moon depends on a combination of all of these physical factors and others.
Wood October 6. As you approach the site from a distance. You can experience this effect closer to home if you ever have a chance to visit Meteor Crater in northern Arizona. By October 20th the part of the Moon w ith m axim um tilt toward Earth is near the crater Desargues. Contributing editor Charles A. Such changing perspectives make observing the Moon endlessly fascinating and new.
The strongest libration starts on October 5th along the south-southwest lim b near the crater Wilson. Through m y mm refractor at 37x. Le G entil 3 is simply a cold. W ithout the dense star fields that it obscures. I see a few touches of color among its stars.
Through a telescope. It is almost opaque and very dark. The brightest stars in this fairly young cluster glitter an icy white or blue-white. M39 appears a little more than across w ith somewhat irregular borders. I count 50 stars. This cloud is only about six degrees from the tail of Cygnus. A 9th-magnitude star along the eastern side of the triangle is the prim ary of the John Herschel double star h H J M39 shows best at a magnification that frames it w ith a generous am ount of surrounding sky.
The nebula tapers and shreds as it crosses the M ilk y Way. M39 is an astonishingly triangular group of bright stars through m y inch reflector at 43x.
Le Gentil 3 is a striking feature when the sky is dark enough to lay the splendor of the M ilk y W ay before your eyes. The cloud is visible without a telescope. A few stars south of the triangle make a short trunk for a very wide Christm as tree. A telescope reveals a few stars in this part of the sky. Training 10x30 binoculars on it. Five of the brightest stars make a squarish figure that nearly spans the cluster.
Once spotted. At x NGC is a 3. NGC marshals 14 stars in a thin. Right ascension and declination are for equinox Kohoutek is easier to see at x. NGC is a pretty cluster residing 32' north of golden 71 Cygni. Could this unseen star have contributed to my perception?
W ith his inch reflector. N G C hovers 7' northeast of a distinctive 2. The haze is oblong. NGC shows a fourth star m aking an arc w ith the two near the center. Folks w ith large telescopes m ight like to acquire the nice little planetary nebula Kohoutek 3 A lasting tribute to the Institute. N G C shows a total of nine stars. M y mm refractor at 48x shows about 50 moderately bright to faint stars in a 25' group w ith borders that are easy to lose track of am id the M ilky Way.
We all did it all: wrote and edited stories, took pictures, drew artwork and laid out the pages. Image The author, at some point between and So I was crestfallen to hear recently that the family farm was up for sale.
The news broke on Hastro-L, a mailing list devoted to the history of astronomy. Word reverberated through the astronomical community, amid rumors that the magazine might close or become an online-only publication. The magazine was financially strong, he said, but had been dragged down by the financial misadventures of its parent company.
Those were heady times for me, my colleagues and our competitors, but that wave soon crashed for lack of advertising. By this time, the expanding Sun will have roasted Earth to a cinder.
Numerous other dwarfs have suffered the same fate, and their rem aining tidal streams litter the M ilky W ays environs. M31 features a whopping globular clusters. It has three noteworthy galaxy companions, each roughly as massive as the M agellanic Clouds: the dw arf compact elliptical M32, the dw arf elliptical M also known as N G C , and the spiral M In addition, M31 has nearly 40 identified dw arf satellite galaxies, w ith potentially many more to be discovered.
It appears that M32 has punched through the disk of M31 at least once. Although not scoring a knockout, this blow very likely cost M31 its grand-design spiral structure, leaving instead two rings of star formation, including the prom inent Ring of Fire that surrounds the galaxys nucleus at a distance of 30, light-years.
First suggested as a possibility in , recent simulations strongly suggest that the Ring of Fire is a consequence of M32 plowing through M31s disk m illion years ago and triggering density waves in the gas that led to a burst of star formation.