Constellation Profile - Sculptor

We continue our quest through the southern constellations with one that is visible from Calgary.  The constellation is known as 'Sculptor' and it was another of Lacaille's constructions in the 18th century.

In late October, Sculptor can been seen directly from Calgary directly above the southern horizon.  The best way to find it is to locate the fairly bright star in Piscis Austrinus known as Fomalhaut.  Look just to the East of this star and you will be in Sculptor.  The sky map below will help.

Star-hop to Sculptor

Lacaille originally named the constellation Apparatus Sculptoris which was to mean 'The Sculptor's Studio'.  It represents a carved head on a tripod table with a mallet and two chisels next to a block of marble.

Lacaille's original depiction is shown below.

Lacaille's Sculptor

Nearly half a century later, Johann Bode moved a few things around and illustrated the constellation in his Uranographia as shown below.

Uranographia Sculptor

I took the time to create a star map of this constellation.  Although I have yet to locate the Bayer stars in it I thought I would still post the map.

Sculptor

The constellation has quite a few deep sky objects scattered throughout its relatively sparse stellar collection.  The Sculptor Galaxy, also known as the Silver Dollar Galaxy, is a fairly bright object in the northern parts of the constellation.  I am curious to see if anyone from Calgary has observed or photographed it from near our home region.  It has been noted that it is one of the easiest galaxies to observe after the Andromeda Galaxy.  This gives me hope to have an observing attempt if I can find a clear view of the southern horizon.  Since at its highest point it is 15° above the horizon it should be fairly visible from Calgary.

Sculptor Galaxy¹

This evening if the weather is cooperative I may seek out Fomalhaut with my binoculars and cruise over to Sculptor.  I want to say I have spent sometime viewing some of the stars that Lacaille made friends with more than 250 years ago!


¹ (Image Credit - ESO/INAF-VST Acknowledgement: A. Grado/L. Limatola/INAF-Capodimonte Observatory)

2017 Week 44: (October 29-November 4)

We are kicking the first week of November off without much excitement in the sky!  Neptune will once again be in conjunction with the bright waxing gibbous Moon followed by a Full Moon later in the week.

Date	Event
October 30	Neptune 0.9°N of Moon
November 3	Full Moon

On Halloween night the Moon will be lighting the sky throughout the prime candy collection time.  It rises just after 5pm and will stay in the sky almost until the Sun comes up.  It will be about 90% illuminated so it will help light your way.

Since there are no major events happening in the sky this week we can cover some constellations hanging over our heads.

The three constellations piloted by the Summer Triangle stars are on their way out into the western horizon.  However, you can still catch Lyra, Cygnus and Aquila along with their deep sky objects for another month or so.

Andromeda is in a good location all Autumn as it cruises across the sky just South of zenith.  In dark skies you will be able to see the galaxy as a faint blur of light.  Use the sharp pointy part of Cassiopeia's 'W' to guide you.

Andromeda Galaxy Location

The Great Square of Pegasus will be located on the western edge of Andromeda's chain of stars.  See if you can find the four corner stars forming the square.

If you want to play with the zodiacal constellations you can have a great pick.  Capricornus the goat fish is setting in the southwestern sky in the early evening.  This is followed by my favourite -- Aquarius which is the current home of our farthest planet: Neptune.  Continuing the water theme is Pisces, the pair of fish which houses Uranus at this time.  Pisces is quickly followed by Aries and Taurus.  The bull is back and making its presence known in the eastern sky.

The image below highlights the ecliptic (path of the Sun) corresponding to the zodiacal constellations.

Early November Southern Sky

The sky should hopefully be clear until the predicted Winter storm hits us on November 1.  I am hoping to observe some more constellations and create profiles for them.  Our continuing tour of the southern constellations will likely transpire during the course of the storm.

This evening (October 28, 2017) will be a star night at Ralph Klein Park from 7pm-10pm.  It is free and perfect for families with kids of all ages.  There will be indoor and outdoor activities with hot chocolate!  Hopefully we will see you out there!

We have tentatively booked the McKenzie Lake Community Centre for a community star night from 7pm-9pm on November 10, 2017.  There will be a quick lecture to teach a topic followed by a highlight of what we can see outside through the telescope.  There will be a craft for kids (and adults if you would like!) and hot chocolate to ward off the cool weather.  Following the lecture we will go outside into the school field to look at the discussed objects through the telescope!  Stay tuned on our Facebook Page for more details closer to the time!

Stay warm and keep looking up!

Constellation Profile - Antlia

In the previous blog the constellations of Nicolas-Louis de Lacaille were discussed.  This great French astronomer mapped the southern stars and compiled an exhaustive record.  Through his work he devised 14 new constellations that have since become official.

The first one we will discuss in Antlia.  Antlia was originally named Antlia Pneumatica and is a representation of an 18th century air pump present in many scientific labs throughout Europe.  An image of an antique air pump is shown below.

Antlia (Air Pump)

The constellation contains relatively faint stars, much like Cancer in the North.  Most of the constellation is visible from Calgary in the mid-evening (11pm) from mid-March to mid-April.  It may require binoculars to see as it will be low in the southern horizon and its brightest star is only 4.28 magnitude.  I see a star-hopping path to the constellation in the early Spring.  I would start at Alpha Leonis (Regulus) in Leo and hop South to Alpha Hydrae (Alphard) then continue South the same distance but line up under Regulus again.  The map below may help you find it.

Star-hop to Antlia

I have not observed this constellation but have provided a log below consistent with my other observed constellations.

Antlia

A German astronomer by the name of Johann Bode published what is known as the Uranographia.  The Uranographia was a star atlas dedicated to showing the positions of the stars and supplying an artistic representation of the sky.  An image of Antlia from his work is shown below.

Uranographia Antlia

This image is an upgrade from Lacaille's original depiction shown below.

Lacaille's Antlia

There are various galaxies located throughout Antlia, the brightest being NGC 2997 at 10.6 magnitude.  There is even a galaxy cluster known as the Antlia Cluster consisting of a couple hundred galaxies.  It is the third closest galaxy cluster to our own Local Group and, unusually, contains no dominant galaxy.

It has been fun learning about some southern constellations when our own sky is cloudy.  Even if I may never have the opportunity to personally spend time under the southern hemisphere stars I can vicariously travel there with sky atlases and diaries of great astronomers.

The Lacaille Constellations

In the middle of the 18th century a French astronomer by the name of Nicolas-Louis de Lacaille made a famous voyage to the Cape of Good Hope.  His story is quite remarkable and I hope to explore it in a later blog post.  Lecaille cataloged nearly 10,000 southern stars during his two year expedition to the Cape.  He introduced 14 new constellations which, as of 1928, have been officially recognized by the International Astronomical Union.  There are a total of 88 constellations in the sky.  Lacaille's contribution accounts for more than 15% of the total.

Nicolas-Louis de Lacaille¹

Lecaille, ever an enlightenment scientist, named his constellations after objects found within a lab.  One, Mons Mensa, was named after a landmark in South Africa -- Table Mountain.  He also split the large Argo Navis into three separate constellations: Vela, Puppis and Carina.

I live in Calgary and am unable to see a lot of the southern constellations from my home.  The lowest declination on the celestial sphere visible from Calgary is about -39°S.  This leaves 39°S - 90°S permanently below the southern horizon.

Lecaille's dedication to exactitude and completeness has inspired me to write some words about each of 'his' constellations.  We are able to see some of them from Calgary.  The list below shows the names of the constellations and their declination range.

Constellation	~Declination Range (°S)	Representation
Antlia	24.5 - 40.5	Air Pump
Caelum	27 - 48.5	Chisel
Circinus	55.5 - 70.5	Compass
Fornax	24 - 39.5	Brazier
Horologium	40 - 66	Pendulum Clock
Mensa	70 - 85	Table Mountain
Microscopium	27.5 - 45	Microscope
Norma	42.5 - 60.5	Carpenter's Square
Octans	74.5 - 90	Octant
Pictor	43 - 64	Easel
Pyxis	17.5 - 37	Compass Box
Reticulum	53 - 67	Reticle
Sculptor	25 - 39	Sculptor
Telescopium	45 - 57	Telescope

Six of the constellations are either fully or partially visible from Calgary.  According to my night sky software, Horologium's borders barely creep across the southern horizon.  However, to have a good shot at seeing any of this constellation's stars you would have to be in deep Southern Alberta.  In fact, I might hold a competition for anyone observing and logging a star in Horologium from Alberta.

Currently at this time of year (End of October), Sculptor, Microscopium and Fornax are in the evening sky.  We will go through each of these constellations in the coming weeks.  I will start with the ones visible from Calgary so you can attempt to view them in the southern sky with your naked eye!


¹  (Image Credit: Mille Le Jeuneux - Stoyan R. et al. Atlas of the Messier Objects: Highlights of the Deep Sky. -- Cambridge: Cambridge University Press)

Letters to the Blogger - Space Age?

I would like to publish the first letter we received in response to news posted on our Facebook page.  If you are interested in contributing anything to our blog we would be more than happy to publish it.

Earlier in the month was the 60th anniversary of the launch of the first satellite: Sputnik.  This moment was captured in rural England with the words of one of our readers.

Space Age?

We all remember a time in our lives when we knew where we were when a certain event happened: Princess Diana’s death, 9-11 and the assassination of President Kennedy.

I remember the first space flight of Sputnik.  I was about ten at the time and we recently had electricity and running water installed in the farmhouse.  We were still trying to come to grips with that reality. Dad had the wireless on to hear the farmer’s forecast for the day: sunny and warm.  The news came on shortly after followed by a news flash that the Russians had launched a rocket into space (Sputnik). This was the stuff of the comic and adventure books my brothers read.

Sputnik

I hurried to eat my breakfast to get to the school bus where the matter could be discussed at length with my peers. The bus was abuzz with the news as we all tried to get our heads around what was happening in the world.  Going through the tranquil, rural countryside the whole concept was truly hard to believe.  We had not long learnt the reason Mount Everest had snow and was cold even though it was nearer the sun.  Mechanization was coming to the farms and the future seemed to be coming fast.

In the following few months it was reported a dog was sent into space – now that really upset the “school bus” crowd who decided they should send one of the scientists instead!

It came to me that there was a much greater world out there and it was up to us and future generations to develop.

-Christine Poole, October 2017

Community Outreach

Over the past few years we have had the opportunity to participate in community outreach programs for astronomy.  These are incredibly amazing events as it seems only a handful of people have had the chance to look through a telescope.  Seeing an object through the telescope for the first time is a unique experience that should be shared with as many people as possible.

Fish Creek Star Night

In order to better enjoy your experience at a public astronomy event there are a few guidelines that may help.

• There is no need to touch the telescope.  Follow the guidance of the operator and just use your eye to peer through the eyepiece.  A lot of people like to grip the eyepiece in their hand.  This is not necessary and can knock the telescope off its intended target.
• If you bring a white flashlight it is important to keep it directed to the ground.  White light will disrupt dark adapted eyes making it more difficult for others to safely get around.  A great solution would be to bring or make your own red flashlight.
• A corollary to the above would be to not look at your phone.  You will have a better experience with dark adapted eyes and can see finer details through the telescopes.
• No flash photography outside.  
• Ask a lot of questions!  We are here to not only illuminate your eyes but your minds as well.
• Attend a variety of events throughout the year.  The night sky changes with the seasons and new, incredible sights will be up each month.

There are some guidelines I have learned that will be of some help to those hosting their own telescope.

• Ensure the safety of the public by bringing your own red flashlight to help people get around.
• Keep electric cords outside of heavy traffic areas or cover them with a mat.
• Show the public where the eyepiece is with your red flashlight and teach them how to look through without touching the telescope.
• Bring a sturdy stool for children to safely look through the eyepiece.
• Come with a list of targets in mind across the entire visible sky.  Many times we only have holes through the clouds so don't confine your target list to one specific area.
• Be careful with the laser pointer and don't let anyone untrained use it.
• Dress as though it is 10° cooler than forecast.

Eclipse 2017

There are many astronomy events around Calgary each month.  You can find out more by checking out our Facebook page and the RASC - Calgary Centre webpage listed below.

http://calgary.rasc.ca/

Many localities throughout the world have astronomy clubs hosting free events.  If you are not from Calgary seek out the nearest astronomy club and learn about their public outreach!

Astronomy for All Ages

As I've mentioned before we are going to start up a monthly local community star night right here in McKenzie Lake.  We have a great facility and the events will be for all ages and will run in all weather conditions.  A telescope will be available to show off some great sights that you can see from suburban Calgary.  If the weather is not suitable there will be indoor activities for both adults and children.

2017 Week 43: (October 22-28)

We are in the last 10 weeks of the year and after a great week we have a less than thrilling one ahead.  It is important to note that the Orionids will still be streaming by in the sky near the peak this weekend.  Last night was cloudy in Calgary but tonight is looking promising.  The Zodiacal Light is also still in season so check that out in the morning twilight if you have dark skies.  The table below highlights some events happening this upcoming week.

Date	Event
October 24	Saturn 3°S of Moon
October 26	Jupiter in conjunction with Sun
October 27	First Quarter

The Moon is just starting its next cycle and will be in conjunction with Saturn on the 24th but you can best see it on the evening of the 23rd.

Saturn

The day has finally arrived for the year.  Jupiter will be in conjunction with the Sun on October 26.  Weeks after this you will start to see our largest planet poking out in the morning sky.  This is good for those astronomers who like to do their work in the early morning.

The Moon will be a waxing crescent until the 27th when it reaches first quarter.

First Quarter

I had the good fortune to be able to teach several groups of Cubs about the sky.  We covered constellations, the Moon, the Solar System and talked a little bit about deep sky objects.

A link to the presentation is provided below:

Cub Scout Presentation

Soon we will be hosting community star nights at the McKenzie Lake Community Centre located at the following address:

16198 McKenzie Lake Way SE
Calgary, Alberta, T2Z 1L7

There will be a short class with unlimited question and answer time followed by looking at the sky in the school field behind the centre.  We will have a telescope setup with specific targets to aim at for the time of season.  We are hoping to run it on a Friday or Saturday evening from 7pm-9pm or earlier as it gets closer to Winter.  It will be open to all ages but we would suggest anyone under 12 be accompanied by an adult.

Stay tuned on this blog and our Facebook page for details.  We are tentatively looking at November 10 for the inaugural event!

The Orionid Meteor Shower

After what is usually a poor showing by the Draconids this month many sky watchers turn to the Orionids for some hope.

The Orionid Meteor Shower comprises the dust and debris leftover from Halley's Comet.  If you missed Halley's Comet back in 1986 you get a chance to see its debris twice a year: The Eta Aquariid Shower and the Orionid Shower.

The Orionids peak around October 21 every year and the best time to see this shower is in the middle of the early Morning.  Orion will be rising in the southeast around midnight and you should start to see meteors soon thereafter.  The radiant point is just to the East of Orion's club as shown in the image below.

Orionid Radiant

The Orionids peak at around 10-20 meteors per hour and are best seen away from the light pollution of urban centres and the Moon.  While you are waiting, take in the sights of the Pleiades Star Cluster or the Great Orion Nebula.  Pack some binoculars to get a better view of these objects.  While looking for meteors be sure just to use your naked eye as binoculars will confine your field of view.

City	Suburbs	Rural	Optimal
5	10	15	23

As with other meteor showers I have provided a log chart for recording your observations.  Please find it below.

Orionid Meteor Shower

Instructions for filling it out can be found: Explore the Universe - Meteor Showers

Binocular Highlights - October/November

Many people I know do not have a telescope but they have a pair of binoculars.  Whether they're used for hunting, birding or creeping they can also be used for astronomy.  In some cases, binoculars offer better views of wide objects than telescopes.  I posted a blog back in March regarding the use of binoculars for astronomy linked below.

http://simonjastronomy.blogspot.com/2017/03/binoculars-what-should-i-look-for.html

Binoculars are a great way to start learning the sky.  Their wide field of view allows for a wide margin of error when looking for a star or other celestial object.  Practice by finding your favourite constellation and see if you can pick out all the naked eye stars with your binoculars.  Count how many binocular fields of view they are away from each other.  Write it down.  This will get you accustomed to aiming them in the correct direction and finding your footing around the sky.  You may get the shakes while looking through them.  There are a few things you can do that can help.

• Hold the binoculars with your hands close to the aperture.
• Lie on your back and rest the binoculars on your eyes.
• Hook them up to a tripod.
• Lean them on a fence or other study object.
• Don't hold your breath.  It may seem like a good idea but it can negatively affect your eyesight among other things.
• Buy image stabilizing binoculars for a small fortune.

I use the pair of binoculars shown below.  They give a wide 4.4° field of view with generous 70mm apertures to collect a lot of light.

15x70 Binoculars (4.4° Field of View)

Once you have taken on several constellations and feel confident you can hop from star to star and can take in some Autumn sights that are beautiful in a set of binoculars.

One of the best places to start is in the constellation: Perseus.  Provided in the link below is a target sheet with objects of interested highlighted in red with the size of a typical binocular field.

Perseus Binocular Observing Sheet

If you follow along with the provided observing sheet you can see that the Double Cluster is a great target.  Just below Cassiopeia this pair of open clusters can be found.  In fact, Gamma Cassiopeiae and Delta Cassiopeiae point in a straight line right to the pair of clusters.  In the same field as these two there is a third cluster known as the 'Muscleman Cluster' or Stock 2.  See if you can see what looks like a person posing with the double bicep flex.

Moving a few binocular fields to the northwest you should come upon Kemble's Cascade.  This region looks like a waterfall of stars cascading down in a straight line.  Lucian Kemble was born in Southern Alberta so feel a sense of Canadian pride as you find this asterism.

A few binocular fields from the Double Cluster in the other direction will get you to M31 - The Andromeda Galaxy.

M31 - Andromeda Galaxy

Below the Double Cluster is a very large cluster of stars around Perseus' brightest star.  This cluster is known as Melotte 20.  A few fields East of this location may bring you to M34; another open cluster.

Another good place in the sky to jump around with binoculars is Aquarius and Pegasus.  The observing sheet for this region is provided below.

Aquarius Binocular Observing Sheet

This area I would consider you require some intermediate skill with your binoculars.  There is a familiar sideways 'Y' shape in Aquarius that I always look for.  It has helped me find Neptune in my early astronomy days.  If you find this 'Y' with your naked eye, stick it in your binoculars.  Scan slightly to the West toward the bright star Altair (Southern Star of the Summer Triangle).  If you are lucky you may pick out a small fuzzy object.  This is the globular cluster M2.  Cruise North of M2 toward the naked eye star Enif.  If you have good eyesight you should be able to split this star into a double.  One binocular field to the West should be another faint fuzzy; the globular cluster M15.

We are hoping to plan some binocular sky nights in the school field in the next little while so keep posted for details!

2017 Week 42: (October 15-21)

Last week was not a very exciting week for astronomy, especially with the snowfall.  However, this upcoming week has some promise.  The table below shows the many sights in the sky that we can check out.

Date	Event
October 15	Regulus 0.2°S of Moon
October 17	Zodiacal Light visible before morning twilight
October 17	Mars 1.8°S of Moon
October 18	Venus 2.0°S of Moon
October 19	Uranus at Opposition
October 19	New Moon
October 21	Orionid Meteors Peak

The waning crescent Moon is cruising back toward the Sun and will meet a few Solar System objects along the way.  On Sunday, the Moon will nearly cover Leo's bright star Regulus.  This should be visible in the early morning twilight sky.  Look for the Moon and you will see Regulus hanging out just to the South.  Two mornings later you may see the Moon spending some time with Mars.  Mars may be difficult to see without binoculars as it is on the opposite side of its solar orbit than us.  This same morning the Moon will be about 5° from Venus.  Unfortunately the close 2.0° Venusian conjunction happens on the other side of Earth to us Calgarians.

Thursday is a big day.  Uranus will be at opposition the same day as the New Moon.  The Moon will not be polluting the sky with light and, from dark skies, you may have a chance to see Uranus with your naked eye.  In the southeast sky you should be able to see the bright stars of Aries in a line.  They will curve down and point to Omicron Piscium.  Uranus will be in the same binocular field as this star.  The map below shows this region of the sky.

Uranus Skymap

The next few weeks the Zodiacal Light will be visible in the morning prior to sunrise.  It is best to have clear, dark skies to observe this phenomenon.  For more information about the Zodiacal Light click on the link below.

http://simonjastronomy.blogspot.com/2017/02/what-is-zodiacal-light.html

At the end of the week the Orionid Meteor Shower will peak.  Since it occurs near the New Moon you can witness them without much natural light pollution.  Later in the week I will devote an entire blog post to these meteors.  The Earth will travel through a region of space inhabited by the dust and ice from the famous Halley's Comet.  The hourly rate is about 20-25 and with dark skies you may be able to catch one every few minutes.

What is an Asteroid?

There has been some discussion in the news recently about the near-miss of an asteroid.

An asteroid can simply be described as a minor planet that is larger than 1m and can reach diameters in the hundreds of kilometers.  They differ from comets in their composition.  A comet is typically made of ice while an asteroid is a rocky, carbonaceous and metallic.  Objects smaller than a meter in diameter are typically referred to as meteoroids that compose the majority of the meteors that fall to Earth.

Sometimes asteroids fall to Earth.  The famous Chelyabinsk meteor that fell to Earth in February 2013 was a 20m wide near-Earth asteroid.

Chelyabinsk Meteor (Image Credit: Marat Ahmetvaleev)

Most asteroids reside in the region of our Solar System between Mars and Jupiter.  A group known as 'Jupiter Trojans' sit in Jupiter's stable Lagrange points 60° ahead and behind of the planet's orbit.

There are a class of asteroids known as 'Near Earth Objects' that may pose a risk to our home planet.  A (NEO) is typically defined as any body in the Solar System that has a perihelion (closest approach to the Sun) inside Earth's orbit or 30% the distance from Earth to the Sun outside Earth's orbit.  This includes more than ten thousand asteroids, more than a hundred comets and a bunch of meteoroids and spacecraft.

Most large (>1km) near Earth asteroids have been cataloged with some still waiting to be found.  Large asteroids like this may cause global damage if they were to hit the Earth.

Asteroid 2012 TC4 has been in the news this week.  It is a small asteroid (10-20m in diameter) that passed about 50,000km from the Earth this morning.  To visualize how close this is, consider that the Moon is between 350,000-400,000km away depending on where in its elliptical orbit it is.

2012 TC4 Close Approach (Image Credit: NASA)

You can see many asteroids from your backyard with binoculars or a telescope.  The asteroid, Vesta, can actually sometimes be seen with the naked eye in excellent dark sky conditions when it is near opposition.  It is quite large (~525km diameter) and relatively high albedo (reflectivity).  The best trick for finding asteroids is to use the Pluto method.  Determine the location of the asteroid using mapping software.  Sketch or photograph the region under observation.  Repeat the next day and see which 'star' in the region moved during that 24 hour period.  That will be your asteroid.  I still have not had the opportunity to find and track an asteroid but I hope to soon.  Tracking the orbit of Neptune last year was my first foray into witnessing orbital motion in the outer Solar System.

Vesta (Image Credit: NASA Dawn Spacecraft)

The Dawn spacecraft was sent in a mission to explore the asteroid belt.  Using ion thrusters it was able to enter and leave the orbit of asteroids.  It visited Vesta (above) in 2011 and moved onto the dwarf planet Ceres in 2015.

2017 Week 41: (October 8-14)

It is Thanksgiving week in Canada and there are a few sights in the sky.  The chart below highlights some of these events.

Date	Event
October 8	Draconid Meteor Shower peaks
October 8	Mercury at superior conjunction
October 9	Aldebaran 0.6°S of Moon
October 12	Last Quarter

The Draconid Meteor Shower peaks in the early morning of Sunday, October 8.  However, if it was anything like last night you will need some great luck.  I was outside for about 45 minutes and had the misfortune to see a grand total of 0 meteors.  The Orionids later in the month may be more prosperous to meteor shower observers.

Mercury will be sitting behind the Sun on October 8 and will cruise into our evening sky once again.  The following evening Taurus' red eye Aldebaran will be very close to the waning gibbous Moon as visible from the Eastern Hemisphere.  We are really striking out for good things in the sky this week!

On October 12 the Moon will be at its last quarter phase.  This will occur at 6:25am in the morning and we can actually witness the exact phase from Calgary.  Exciting?  No.

Last Quarter

However, not all is lost.  We can be thankful that the following week has better sights for us.  Next week we can look forward to a better meteor shower, a planetary opposition and a few great conjunctions!

Fish Creek Park and the Royal Astronomical Society of Canada are hosting a star night this upcoming Saturday October 14!

More information can be found below:

http://calgary.rasc.ca/fishcreek2017b.htm

Also check out our facebook page below for up to date information about several other events happening in October!  There will be members at Fish Creek set up with their telescopes to see some great objects throughout the October sky.  Also, there are many exhibits and activities inside for the whole family.  Come join us for this free event!

www.facebook.com/simonjastronomy

Have a great and safe Thanksgiving weekend!

The Draconid Meteor Shower

There is a lesser known meteor shower that peaks in early October.  It is known as the Draconid Meteor Shower because they radiate from the constellation: Draco.  The best way to find Draco is to use the Summer Triangle as a guide.  In the evening throughout early October, the bright star Deneb will be sitting almost immediately overhead.  It forms a triangle with the brighter star Vega and another bright star to the south, Altair.  Using the diagram below as a reference look just to the northwest from the line between Deneb and Vega.  This will be your radiant point, right out of the head of the Dragon.

Draconid Radiant

The Draconid Meteor Shower occurs when the Earth transits a field of cometary debris from 21P/Giacobini-Zinner.

Several times a zenith hourly rate has peaked over a thousand meteors per hour.  However, we are not expected to have such a storm this year.  Also, if there is a bright Moon out it will pollute our skies wiping out any faint meteors.  However, still look up when it is dark and stare at that spot I pointed out in the map above.  You may get lucky.  Be patient.  .

I have provided a link below if you would like to create your own chart like I did with the Perseid Meteor Shower.

Draconid Meteor Shower Template

Instructions for filling it out can be found: Explore the Universe - Meteor Showers

Explore the Universe - Venus

Venus is the second closest planet to the Sun and the closest planet to Earth.  It is the brightest object in the sky besides the Sun and the Moon.  It has been recorded for millennia and finds itself in many myths.  Venus was the first planet in the solar system that our spacecraft visited (1962) and also the first with a lander back in 1970.

The image below was taken when Venus was a waning crescent.

Venus

Some of the fast facts about Venus are shown below.

Orbital Period (Year)	225 days
Rotational Period (Sidereal Day)	243 days (retrograde rotation)
Axial Tilt	2.64°
Surface Area	0.902 of Earth
Volume	0.866 of Earth
Mass	0.815 of Earth
Gravity	0.904g
Surface Temperature (mean)	462°C
Surface Pressure	9,200 kPa

Many of the items in the list above are absolutely fascinating. 

A year on Venus is shorter than its day! 

It is very close to the same size as the Earth. 

It is the hottest planet in our solar system with a temperature around 462°C.  The temperature on Venus does not fluctuate very much and remains approximately the same whether Venus is facing the Sun or not.  This is quite different than Mercury which fluctuates between -170°C and 450°C.

The atmospheric pressure on Venus is a whopping 9,200 kPa!  This would be similar to being over a kilometer under the Earth's ocean.  The winds on the surface of the planet only reach to a few km/h.  However, since the pressure is so high those light winds are enough to move rocks around and kick up a significant amount of dust.  The winds higher in the atmosphere can reach and amazing 700km/h.

Venus, just like Uranus, also rotates in the opposite direction to the other planets.  They would rotate clockwise as viewed from the North Pole.

Venus lacks plate tectonics but has many large volcanoes (many more than Earth) that periodically (half a billion years) resurface the planet.

Keep up to date on how you can see this bright planet by checking out the latest Weekly Update!

Good luck in your planet viewing!

Explore the Universe - Meteor Showers

The Perseid Meteor Shower is long over but there is always another shower around the corner.  In fact the Draconids are peaking this weekend.  I do not anticipate it being very exciting.  The Full Moon shines brightly that evening and will drown out any faint meteors.  On occasion, throughout the 20th century, the Draconids have peaked in the several thousand per hour.  This is known as a meteor storm.  It never hurts to look up on the evening of a meteor shower in case you get lucky.

An optional observation on the Explore the Universe list is a meteor shower.  It is described as follows:

Sporadic meteors can be seen on most dark, clear nights. Meteor showers are regular events occurring at different times throughout the year with high rates of meteors appearing to come from a specific zone or radiant in the sky. Look for a dark moonless night and be prepared to stay up late, as the best observing is usually after midnight.

A meteor shower is caused when the Earth passes through a stream of debris that is typically left over from a comet.  When a comet approaches the Sun the ice from it vaporizes leaving a stream of debris mostly the size of dust particles.  The name of the meteor shower is indicated by the constellation they seem to radiate from.

A group of about 20 of us spent time East of Calgary where we could see a less light polluted northeastern sky.  It was before midnight and we perhaps caught a dozen Perseids.  I decided to test the idea that the best observing is after midnight.  From the backyard between 2-2:30 I witnessed 9 meteors radiating from Perseus.  Given the light pollution from the city and strong waning gibbous Moon, 9 seemed pretty good.

There are many ways to record a meteor shower.  The most common way is just to sit back on the grass and just watch the amazing view.  Some people do time-lapse photography to catch as many as they can.

In the link below, Alan Dyer discusses some techniques for photographing a meteor shower.

https://amazingsky.net/2015/08/06/how-to-see-shoot-the-perseids/

However, if you want, you can make your own chart of observations.  There are several citizen science projects involving meteor showers.  You can submit your results that will be put into a database that scientists can use to study this phenomenon.  This was the first time I actually made a record.  I guess you could call it practice for the next one.  Each arrow on the below image represents the direction and magnitude of the meteors.

Perseid Meteor Shower

Stay tuned for upcoming meteor showers.  The Orionids will peak later this month and the Moon will be tucked away near the Sun during the night.  The best thing is, they peak on a Friday night!  Let's hope the weather is good!

Be sure to check out the Fish Creek Star Night!  This is a free, fun activity for people of all ages.  Come down to the Fish Creek Environmental Learning Centre for a great interpretive exhibit of nature and the sky!  Check out the link below for more details!

https://www.facebook.com/events/1765114146854576/

2017 Week 40: (October 1-7)

It is now October and the Fall constellations are making their way into the sky.  I saw the Pleiades Star Cluster last night poking up from the eastern horizon.    This means Taurus and Gemini are going to be back in the evening sky shortly.  Orion in its grandeur will soon make its presence known to us before we go to bed.

We also celebrate the sesquicentennial blog entry today reaching a wonderful 150 since the beginning of 2017!  The table below highlights what's up in the sky this week.

Date	Event
October 3	Venus at perihelion
October 3	Neptune 0.7°N of Moon
October 5	Venus 0.2°N of Mars
October 5	Full Moon
October 7	Mars at aphelion

This week Venus will be at perihelion and Mars will be at aphelion.  I'm sure some astrologers are getting rich this week.  As described in the Solar Eclipse FAQ #1 perihelion occurs when a body in an elliptical orbit is at its closest to the Sun.  Aphelion, on the other hand, is when a body in an elliptical orbit is at its furthest from the Sun.  This does not really mean much for visual observers it's more of an interesting fact.

However, in between these two events our neighbouring planets will be in conjunction.  Mars and Venus will be within 0.2° of each other in the sky.  Sigma Leonis comes along for the ride too and will be within 0.3° of Venus that same morning.  They will sit tighter together than the Leo triplet 7° away.  Look in the East before sunrise and throw some binoculars over your eyes to catch the conjunction.  The map below gives you a rough idea of where these planets can be found.

Venus/Mars Conjunction

The Full Moon will be on display this Thursday and it is known as the Harvest Moon.  An article about this Harvest Moon is found below.

https://www.space.com/38272-october-full-moon.html

A Harvest Moon is the closest Full Moon to the Autumnal Equinox.  It is so named because it allowed farmers extra light to harvest their crops before artificial lighting.

We are expecting a winter storm this evening but the signs of it are not yet showing.  After the expected storm the weather picks up and is seasonal for the rest of the week.  This should be perfect time for some astronomy!  Look up and catch some familiar sights in the sky this week!