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A look into October’s sky

Happy Thanksgiving Halloween month! 

The nights are getting longer as we’re heading for that time of year once again when, on Oct. 31, kids of all ages will dress up in costumes and travel through neighbourhoods in search of treats and fun.  

It’s also quietly become an opportunity for astronomers to connect with their neighbours and friends they haven’t met just yet.  

Halloween night has become a time when I place my telescope out on the front lawn and offer views to the various goblins, superheroes and thrillseekers dropping by for treats. Many parents accompanying their kids have also had a look in my Halloween telescope and helped themselves to views of the ringed planet Saturn or some mountains or craters on the moon.  

Is astronomy better than candy? Uncertain, but it is surely less calories. But let’s now consider the viewing opportunities for the month of October. 

 

Comet

Oct. 7 will be the best opportunity to view Periodic Comet 103P/Hartley 2 when it (hopefully!) glows at fifth magnitude. 

The best views will be obtained from a dark site, so using binoculars within city limits is advised. Oct. 7 will find the comet only one degree below the famous Double Cluster in the constellation Peruses the Hero. Perseus is located in the NE sky direction. 

Here’s a small star hop to assist in locating the visual field. Cassiopeia the Queen is a W-shaped constellation found above Perseus. So first look NE and locate a large W-shape high in the sky. Take the center star in the W-shape & “hop” visually down to the lower left star in the same shape.  

Keep heading down and away from the constellation until you have travelled the same distance as between the two stars in the beginning of the star hop. Congratulations, you have arrived in the general area of the Double Cluster. 

If you have binoculars, do take a moment to observe these beautiful binocular objects. Expect to find extensive, bright, colourful groupings of stars. Not to over look the original objective, don’t forget to sweep down one degree to find Comet Hartley 2!   

Conjunctions

(When two or more celestial objects appear together in the night sky.)

For Oct. 6: If you find yourself awake and standing outside about one half hour before sunrise, don’t worry. It’s simply a great time to spot the tiny, star-like planet Mercury when it is located low on the eastern (I) horizon to the lower left of the moon. It’s a naked eye observation but binoculars are optional.

For Oct. 9: Instead of observing in the night sky, try observing in the evening sky about one hour before sunset. Look at the SW horizon for the brightest planet Venus about four degrees to the lower right of the moon. This a naked eye observation that would work with  binoculars. CAUTION: WHETHER NAKED EYE OBSERVING OR WITH BINOCULARS, NEVER LOOK AT THE SUN. This observation should be quite safe since the sun will be 27 degrees to the right of the conjunction.

For Oct. 19: Two hours past sunset, look SE to find the bright planet Jupiter nestled only six degrees below the moon.  

Meteor shower

For Oct. 21: Before dawn marks the peak of the Orionid Meteor Shower. 

Meteor showers happen when planet Earth’s orbit passes through the tail of a comet. The Orionid Meteor Shower is based upon arguably the best known comet of all: Halley’s Comet. The meteors happen as dust particles from the comet interact with Earth’s atmosphere. Showers are named for the host constellation containing the radiant point or source of the shower.  

Orionids come from the constellation Orion the Hunter but sporadic meteors come from all directions in the night sky.  Unfortunately this year, the shower will be competing with a bright moon. 

Planets

(Where and when to see them)

Evening: Venus (W), Mars (SW) (Mars disappears into the sunset later in the month), Neptune (S),
EAll evening and toward dawn: Jupiter and Uranus (E)

Dawn: Mercury (E) available only the first week of October before it disappears into the sunrise, and Saturn (E) rises higher each morning. 

Clear skies!

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As we promised in the Aug. 6 edition of Country Asides, here is the continutation of The Sky Guy’s celestial wisdom for the month. Here, Harris Christian tells us where and when to get the best view of the planets in the August night sky.

Evening:

Venus is the brightest planet in the night sky and shines at visual magnitudes of -4.3 to -4.6 during August. The brighter the object, the more negative the number. For example, our Sun is rated at -26 magnitude. And NEVER look at the Sun with the naked eye! I have been safely observing the Sun since 1993 in a telescope equipped with a solar filter enabling safe views.

Back to Venus, after locating Venus, scan about 20 degrees down to the lower right to locate tiny, star-like Mercury. In comparison to bright Venus, Mercury shines at magnitude 0.1 to 0.7 later in the month. So it will appear much fainter.

Early in the month the planets Mars and Saturn may be found above Venus but move away as the month progresses. Look west to locate the Red Planet Mars and the Ringed Planet Saturn. The amazing rings of Saturn are visible even in telescopes of small size. I regularly view them in my two smaller telescopes measuring only 90 and 114 millimetres.

Back to the planets. For brightness, Mars glows at magnitude 1.5 while Saturn will be magnitude 1.1. In contrast to red Mars, Saturn appears a shade of pale white to my eye. As an aid to locating planets, remember that they shine brightly like stars but do not twinkle like stars.

Over time, astronomy is a lot like fishing: patience and refinement of your observing techniques will yield eventual better results. The dwarf planet Pluto may be found in the constellation Sagittarius (south) but you require a telescope to make this observation. Pluto can be a faint object at an extreme visual magnitude of 16.1. That magnitude would require a much larger telescope than the small instruments previously mentioned. I’ve tracked Pluto down a few times and found the exercise to not be as rewarding as observing the other planets.

Pluto appears to look much like a tiny star without any visual details like the other planets offer. Once you locate it, it’s useful to either sketch or photograph the field of view. Locate the field of view one hour later, using your sketch or photo and you’ll notice that Pluto has moved away from its former position. That confirms that you are looking at a planet that is in orbit. Planets move but stars do not. The term “planet” is based upon the Greek word for “wanderer.”

Later in the evening:

Neptune rises around sunset but will be tough to locate at magnitude 7.0. Typically, the average unaided eye begins to detect objects at about magnitude 6.0 so visual aid will be required for this observation. It’s a small target. Try looking later in the night after it has risen higher in the night sky.

Neptune will be located near the constellations Aquarius the Water Bearer and Capricornus the Goat in the southeast. When you find Saturn setting in the western sky, Uranus will be rising in the east. At sixth magnitude it borders at the edge of naked eye visibility but is an easy binocular target.

Certainly more spectacular is the gas giant planet Jupiter, glowing at 2.9 magnitude. Telescopic views of Jupiter show the four most visible moons Europa, Callisto, Ganymede and Io. These tiny moons were discovered by Galileo and offer very entertaining views as they change locations while orbiting Jupiter each night.

They travel across the planet and display shadows across the surface of Jupiter. This event is called a Shadow Transit and can be observed in a telescope. The moons also disappear behind Jupiter and reappear at a later time. This event is known as an Occultation because the moon is being blocked or occulted by the planet. I’ve once even observed one Jovian moon (referring to a moon of Jupiter) occult another Jovian moon. I first noted only three moons visible but as I watched, one moon began to change shape from round to oval and then separated into two moons. It was a cool event.

Not to be overlooked, the surface of Jupiter displays dark bands of colour at the equator plus both north and south hemispheres. Within the dark bands one can observe white-coloured festoons, resembling white spots (not the musical group!). There is also a salmon-coloured area known as the Great Red Spot that appears with each rotation of Jupiter. This object has been observed for over 300 years and is essentially a giant atmospheric storm. This spot is oval shaped and changes size but measures about 13,000 kilometres by 30,000 kilometres on average.

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Clear skies

August is upon us and we are amidst lengthening dark nights and warm observing temperatures. This month we are blessed with optimum conditions for viewing the Perseid Meteor Shower due to the absence of the moon during the peak of the shower activity. 

When you look due south at night this month from a dark sky location, you will be gazing into the very heart of our own Milky Way Galaxy. This is truly where we all live, our galactic address.

Looking south when you see the wide, bright clouds of the Milky Way extending up from the horizon and arching overhead, the very brightest portion down toward the south and southwestern horizon contains the constellation Sagittarius the Archer. Many people identify this constellation as a teapot-shaped group of stars with cloudy wisps of smoke located just above the spout. 

A closer examination of these supposed smoke wisps will reveal the closest trio to be two nebulae and an open star cluster. Nebulae, the plural of nebula, refer to what looks like hazy cloud-like objects that contain various gasses and dust lanes. An open star cluster is a closely grouped pattern of many stars that appear together. 

If you sweep upward from the horizon to the zenith (a point directly overhead) with a visual aid such as binoculars, you’ll see stars, nebulae and star clusters throughout the rich field of the Sagittarius Arm within our own Milky Way Galaxy. 

Conjunctions (When two or more celestial objects appear close together in the night sky)

Aug. 7

Three planets! About half an hour past sunset, look near the western horizon for a Venus-Saturn-Mars conjunction. Using binoculars will enhance this observation. Venus will be the brightest planet and you may also spot tiny, star-like Mercury 18 degrees away to the lower right of Venus. About one hour past sunset look for the ringed planet Saturn only three degrees above. Mars will appear five degrees to the upper left of bright Venus.

Aug. 12

The peak of a meteor shower and four celestial bodies gathered together? Tonight is the peak of the Perseid Meteor Shower and only 15 minutes past sunset look westward for an eventual Mars-Moon-Venus-Saturn conjunction. The crescent moon will be down near the horizon with bright Venus only six degrees to the upper left. (For measuring degrees in the night sky, try holding a closed fist at arm’s length: that would approximate 10 degrees. A little more than half of your fist, three or four fingers, will represent six degrees.) About half an hour later as the sky darkens, look for the red planet Mars only three degrees to the upper left of Venus and then Saturn to the upper right of Venus. Don’t forget to watch for Perseid meteors tonight!

Aug. 18

I recommend using binoculars to catch tonight’s conjunction of Venus and Mars near the west-southwest horizon. If you do, both planets will visually appear within the same binocular field. One hour after sunset, Mars will be located only two degrees above Venus.

Aug. 26

For our last conjunction for this month, try a Jupiter-Moon pairing. Look west-southwest about one hour after sunset and you’ll be able to locate the bright planet Jupiter less than six degrees below the crescent Moon.            

Meteor shower (possibly the best of 2010!) 

This year, the peak of the Perseid Meteor Shower occurs during a span of moonless nights. Often, the presence of our bright moon thwarts good observing opportunities – but not this year.

The shower will peak late Thursday, Aug. 12 into Friday, Aug. 13, but be sure to have a look on the previous evening as well. A couple of days prior and after a peak period will probably still yield results. 

What exactly is a meteor shower?

Meteor showers occur monthly as seen from our planet. A meteor shower is a time when Earth passes through the tail of a comet. Comet tails are debris fields left behind as the comet travels through space. The American astronomer Fred Whipple coined the term “dirty snowball” as the definition of a comet – an apt term since comets have a rocky core covered by layers of ice that become ingrained with rocks and space debris during the comet’s orbit. The parent comet for this shower is Comet 109P/Swift-Tuttle.       

Meteor showers are a free gift. No optical equipment is required. Optimum viewing will be found in a dark location away from the light pollution of a big city. Summer nights can prove cool over several hours of darkness so be sure to have a blanket or sleeping bag on hand. Chairs or lounge chairs are an asset. Make sure you’re comfortable. And unfortunately, bug spray may also be an asset.  

Don’t feel you only have to look in one direction. The radiant point (referring to point of origin) for this shower is the northeast sky, but meteors may be found travelling in any direction. 

You will find the host constellation Perseus in the northeast and hence the shower is named in recognition of the host constellation. Expect to see up to 60 meteors per hour.   

…to be continued in Country Asides Friday, August 13th.

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Don’t despair! The days are growing shorter daily with more hours 

of darkness. But in perfect balance we are in the midst of long evenings 

of sunshine and warm weather. That’s the Yin and the Yang of Canadian 

summer nights.  Celebrate that balance and enjoy everything nature has to offer. 

ASTEROID

Like comets, asteroids travel through the universe and are visible from Earth periodically or sometimes are visible only once in a lifetime because their orbits are too vast.

Asteroids differ from comets in that they are made of rock while comets have been described as “dirty snowballs.” They often have a rock core encompassed by layers of ice containing rocks.

This month’s asteroid is called Ceres and it will be passing through the constellation Ophiuchus the Serpent Holder. You can locate it in the northern summer sky on the opposite side from the constellation Orion the Hunter. Orion is a popular shape in the night sky and many people can locate that stick-figure shape containing three belt stars.  

COMET 

Woohoo! We have a comet in the neighbourhood. But you will require a telescope to see it when it visually peaks at 8th magnitude. In English that means the comet is too faint to be seen without visual aid such as a telescope. 

Under pristine dark sky conditions, the limit of naked eye seeing is in the 6th magnitude range. But at a star party I attended a few years ago, a lady from Manitoba spotted a 7th magnitude star with her naked eye. 

By the way, a “star party” is an event where astronomers camp out in a dark site and stay up all night observing. The events usually include speakers on various topics, door prizes, telescope judging, astrophotography contests, binocular sky walks, and lots of recreational activities. Last year at the Saskatchewan Summer Star Party there was an exhibit of celestial-themed quilts. From a comet to a quilt!

PLANETS 

(where and when to find them)

Evening (west): Mercury, Venus, Mars & Saturn (all visible with the naked eye)

Midnight: (east): Jupiter (visible with the naked eye) and Uranus (need visual aid)

Morning: (south): Jupiter (visible with the naked eye) and Uranus (need visual aid)

CONJUNCTIONS

July 3: This conjunction or close pairing of two celestial objects is perfect for early risers. About 90 minutes before sunrise, since you’re already awake and keen for an observing opportunity, locate the moon with the nearby bright planet Jupiter approximately 7 degrees to the lower left of the moon.  

Seven degrees is estimated by holding your closed fist at arm’s length and sighting past it with one eye.  Seven degrees would represent the width of 70 per cent of your fist. It’s just an estimate since everyone has different-size hands. But there will be no mistaking the bright planet Jupiter. Note that Jupiter is also obvious because it glows but does not twinkle. Remember: stars twinkle but planets do not. All this time, Jupiter is spending time within the constellation Pisces the Fish. So if you’re looking at Jupiter right now, you are also looking at the constellation Pisces.  

For those early risers owning binoculars, locate Jupiter and you may be able to see the much fainter planet Uranus only 2 degrees to the right of Jupiter. Two degrees is the width of two fingers held at arm’s length. If you are able to detect colour, Uranus has always looked blue-green to my eye.  

Before I move on, here are some final considerations about measurement in the night sky. A fingertip at arm’s length covers approximately 1 degree. Both the sun and moon are each one half degree wide. NEVER LOOK AT THE SUN. But do look at the moon. Holding out your thumb at arm’s length, one can easily cover the moon. Try this when the moon is rising from the horizon and appears huge and try it again when the moon is riding high in the sky. You thumb will easily cover both objects even though they seem disproportionate. And the Big Dipper is 25 degrees across. Finally looking from the horizon to the point straight overhead (the zenith) is 90 degrees.

July 14: Looking west (W) toward west-northwest(WNW) about 40 minutes after sunset, locate the waxing crescent moon along with the very bright planet Venus about 7 degrees to the moon’s upper right. Your eye will be looking pretty close to the western horizon with Venus being about 10 degrees above it. Here’s another observing opportunity: Venus is bright and obvious but tiny, star-like Mercury is sitting not far above the WNW horizon and resembles a star but not a twinkling star. That’s one way to identify it. Starting at Venus, look down toward the right at a 45 degree angle and visually continue in a line until you spot Mercury. Back to Venus. 

Try the same visual exercise but take that same line in the opposite direction up and to the left. You will be able to locate the red planet Mars because of its colour. Mars is red and does not twinkle.

Continuing upwards and left of Mars you will be able to spot the ringed planet Saturn. Again, it’s significantly bright and glows steadily. Like the other planets, no twinkling.

Saturn is a visual treasure in a telescope and even moderate-sized telescopes will reveal the magnificent rings. So this opportunity is there for the taking but if this is your first attempt at sky watching, don’t be discouraged if you are not locating the celestial objects. You certainly won’t miss the moon! From the upper left, about 20 degrees above the W horizon is Saturn, next down to Mars, then bright Venus and finally tiny Mercury at the WNW horizon.

July 15: Again looking W around one to two hours after sunset, locate the moon down near the horizon. This time we have grouping of three planets with brightest Venus to the far right of the moon. The red planet Mars will appear 7 degrees above the moon while Saturn will be 10 degrees to the upper left of the moon.

Don’t be afraid to try measuring these distances with the arm’s length technique previously described. You won’t look too silly in the dark, right?  Amaze your friends with your new knowledge.

July 30: Ah, fresh crisp morning air. Around one hour prior to sunrise, Mars and Saturn will be found near the W horizon. This event is an interesting one in that Saturn will appear less than 2 degrees above Mars. Don’t forget your finger measurement! If you own binoculars, this conjunction will make a fine view.

July 31: Not requiring sleep would be an asset in astronomy but we’re all human. Again one hour before sunrise you can look to the south, find the moon and bright Jupiter will be 7 degrees below the moon.

METEOR SHOWER               

Yes, we have one this month. Let’s take a moment to remember what a meteor shower really is. People sometimes call meteors “shooting stars.”  When a meteor survives passing through Earth’s atmosphere and lands on Earth, it becomes a meteorite. A meteor shower is observed when the planet Earth passes through the remnants from a comet’s tail.  The tail is a debris trail of particles that ignite upon contact with our atmosphere. Unfortunately for us this month, the peak of the shower occurs only three days after a full moon & bright moonlight will wash out good viewing opportunities. The Delta Aquarid Meteor Shower peaks before dawn on July 28. The name “Aquarid” refers to the home constellation of Aquaris the Water Bearer. 

Within that constellation will be a Radiant Point or point of origin for the shower. f you want to have a look anyway, look south at the moon and you’ll also see the planet Jupiter to upper left of the moon.

A final comment about future meteor showers. When you know a shower will  peak on a certain date, consider watching for a couple of nights before and after the peak date. “Peak” simply means the date of maximum activity but the Earth passes through the comet debris over several days.

But wait until next month for one of the best meteor showers of the year

SOLAR ECLIPSE

This event is not in North America but can be seen from Easter Island and southern South America. I mention this to remind people that events happen all the time, day and night.  We all appreciate the sunlight and warm temperatures but don’t necessarily receive sunlight from the same position of the globe upon which we all exist. 

This event happens because the moon passes in front of the sun and blocks it from sight as seen from the Earth. This blockage is a small shadow along a strip of the Earth’s surface.  The strip is called the path of totality and means that the view of the sun will be blocked for small period of time.  At the maximum point, the sun will be blacked out for over five minutes. One can expect the temperature to drop, and stars and planets may be seen in the “sudden” night sky.

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