Night Sky Course Lecture 1

Mississippi Valley Night Sky Conservation (MVNSC):

  “The Night Sky Around Us”

Program developed by:

Mississippi Valley Conservation
Authority Royal Astronomical Society of Canada
Ottawa Astronomy Friends

Instructor: Pat Browne
Assistants: Andrew Lindstrom, Bob Hillier

Course runs each Friday during the month of April Course time: 19:45 – 22:00 formally with priority given to observing when clear

5 lectures covering observations of the night sky are all available under the section Science and Nature/NightSky at the Millstone News www.millstonenews.com:

1. Celestial Sphere and our Place within it – the vast expanse of interstellar space
2. Lunar Observations (When the Moon phase is around ‘first quarter’)
3. Stars within our galaxy  – the Milky way (our island home)
4. Star clusters, Open Clusters within the disk of the Milky Way, Globular clusters , in a halo around the Milky way
5. Galaxies beyond our own Galaxy

Observing Techniques: All of these items can be observed using simple aids

• Star charts
• Astronomy applications – The local night sky as it appears April 4th,  2014.  Earth Centered Universe 
• Logbooks and handbooks

Postings for the course, and discussion group are at the Mill of Kintail Night Sky Conservation Yahoo Group.

Mill of Kintail – Night Sky Conservationists
(You can join here by requesting invitation)

Activities include …

• Moonlit walk to Fred Lossing Observatory (FLO)
• Dark Sky observing
  • with Planispheres (no optical aid) for Constellation Practice
  • Observing with binoculars and telescopes
• Lunar and Planetary Observing (Special event – April 14 2014 – Mars Viewing!)
• Daytime – Solar  Observing using a special telescope filter
•  Guest Lectures
  • Frank Marshall on Mars Exploration, *Sanjeev Sivarulrasa, astro-photographer
• Instructional Videos and tips on Night Sky Conservation

Night Sky Conservation:

By-law 03-62 in partnership with Mississippi Valley Conservation and the Royal Astronomical Society of Canada

•  Ensure the continued preservation of our dark skies in Mississippi Mills with a bylaw to regulate the potential risk for light pollution from poorly designed light fixtures.
• Outdoor Light fixtures should be shielded so that the night sky is bright by artificial light,
•  Celestial objects in outer space remain visible on clear night –  comets, distant suns, clusters of stars, and galaxies
• Humans need darkness as well as light. We cannot sleep well with constant artificial light around us – Light pollution causes physical and psychological discomfort
• Night vision is different from day vision. Humans suffer from bright light glare finding it hard to adjust to the night sky.
• This enhances public awareness of the night sky environment and encourages active research in the area of astronomical discovery such as cometary discovery.

CONSIDER THIS… Our Dark Sky Site – Long History of Looking up

Mississippi Mills is the home of the Fred Lossing Observatory (FLO) maintained and operated by the Royal Astronomical Society of Canada (RASC):   http://ottawa-rasc.ca/wiki/index.php?title=Fred_P._Lossing_Observatory   Located at the Mill of Kintail Conservation Area, it was built by the scientific community with high-quality optics from the National Research Council of Canada. Thanks to the continued preservation of the night sky at the Mill of Kintail, the local dark skies have permitted the visual discovery of 5 comets, making FLO the only observatory in Canada to do this.

This is comet Garadd – captured Spring 2012 – images courtesy P. Browne

Star ship Earth within its Celestial Sphere

What we see in the Night Sky depends on:

1. Our Latitude on earth Our Night Sky Location  – Northern Hemisphere, Mid-Latitude (45 degrees)

This sets our horizon, and what is above or below it when we look up at night. Objects below the horizon cannot be viewed. Certain celestial objects remain permanently below our horizon. As we stand on the earth looking up, 1/2 of the sphere is obscured by the earth itself. This hemisphere is bounded by the plane we call the horizon plane. During the day, the dazzling brilliance of the daytime star (the Sun) overwhelms everything else in the sky. Its light illuminates the atmosphere so that stars in the sky are not visible until the Sun sets below the horizon.

2.  Time of Year: The Constellations change around our Earth Orbit The sky in different times of year: Because our orbit around the sun changes our direction in space, it changes what constellations are visible when the sun is below the horizon As the earth orbits around the Sun in the year, the night sky will contain different objects, different constellations. Here is a link describing what happens to our sky as we travel in our yearly orbit: A Year on Earth.

Note – Small errata: The position of the sun on vernal and autumnal equinox is 1/2 point on the graph midway up the y-axis – not the cross-over point on the Analemma

Courtesy R. Dick, The Celestial Sphere, Starlight Theatre

Looking Out Into Our Night Sky with the help of the Celestial Sphere

We are all travelling together through space on a giant star ship–our home planet Earth, our star ship. We can see:

• Nearby neighbours like the moon, and planets – closest objects to spaceship Earth 7 other satellites of the Sun
• Beyond to  more remote light sources which originated in our galaxy. The star patterns we see at different times of year are patterned into Constellations. .
  • A constellation is different from an asterism . Constellations are groupings of stars that are recognized as fixed star patterns on the celestial sphere. A set of 88 officially recognized constellations completely covers the sky.. The brightest stars help us delineate their form.
• Milky Way – more than 200 billion stars. All of these celestial objects form a majestic backdrop to the velvet canvas of night–the period each day when our spinning planet carries us away from the day time star in our sky, the Sun, so that we can gaze at the universe beyond.

• Next lecture we will start to study systems of stars, star clusters that are found within constellation boundaries that we will learn to recognize. We use constellations as a set of featured patterns that guide us to finding our binocular or telescopic object, such as a star cluster or a galaxy. Everything seen in the form of stars in a constellation, or star clusters is found within our own Milky Way galaxy; however we can look out and see other galaxies, particularly in the spring time because our pointing direction in our orbit at this time of year projects outward away from the disk of the Milky Way galaxy .

Our Nearest Neighbours

Our solar system: planets, comets and asteroids wanderers around the Celestial Sphere…they move night after night in relation to Earth

The Planets and Cometary objects in our Solar System are visible to us when their orbit takes them away from the glare of the sun into our night sky: Hence we do planetary and comet observations when they appear above our horizon as they travel along the ecliptic (or, for comets, on their eccentric heliocentric path) after the Sun has set below the horizon. In different years, we will see planets at different times. Their position is not fixed on our celestial sphere. They are wanderers, and may become morning or evening ‘stars’ depending on their proximity to the Sun.

Our Solar System: Read more here @ https://millstonenews.com/2014/04/night-sky-course-planets-earth-and-orbits-around-the-sun.html

Our Distant Neighbours – Stars and Constellations on the Celestial Sphere

With a 3-dimensional Celestial Sphere we can peer out from the inside and find our stars for a particular time of year.The little globe of the earth is placed to orient the observer according to the ring of the local horizon as shown by the horizon ring. Once, the Latitude, Longitude, and Date and Time of the observer are arranged, the appearance of the constellations are fixed, and the stars are ‘observed’ looking from the inside out.

We can also use a 2-dimensional aid , a Planisphere to determine what’s up in the sky tonight:

Planisphere – Plan your Sphere!

Looking at the Southern Horizon On April 4 2014 @ 9pm for a Latitude of 45 degrees

Constellations in April: Southern Horizon – on or near your meridian

• Leo (with Galaxy Triplet), Virgo, Cassiopeia, Draco, Corvus

Constellations in April : Western Horizon – about to set (winter constellations)

• Setting in the West are Gemini, and Orion

Constellations in April: Eastern Horizon – preview of summer

• Rising in the East is Hercules and Ophiuchus

Starhop through the Constellations “Follow the Arc to Arcturus … Speed down to Spica in Virgo”

We can use starhopping techniques to locate a galaxy! Locate M51, the Whirlpool Galaxy just below the handle of the Big Dipper

The celestial sphere presented in this lecture is set for April 4 after 9PM

• Mars is visible and Jupiter is starting to set. When you observe them in a scope or even binoculars, notice the configuration of Jupiter’s moons. They change every night. See
• Bright stars can be identified such as Regulus in Leo – which is also a multiple star system
• Open Star Clusters such as M44, the magnificent Beehive cluster – visible naked eye as a swarm of stars!
• Globular Star Clusters such as M53 containing tens of thousands of stars; these lie scattered throughout the sky
• Galaxies and Clusters of Galaxies (in Leo and Virgo) are very abundant as we are looking out of the plane of the disk of our galaxy!
• Next time we will see the celestial sphere has turned a bit. We will notice this as we look up! For Understanding the Celestial Sphere: see https://millstonenews.com/2014/03/night-sky-course-understanding-the-location-of-stars.html

For Observing Tips see: https://millstonenews.com/2014/04/night-sky-observing-tips.html

For Astronomical Objects found in the Catalogues–Read More here: http://www.mvc.on.ca/astronomical-catalogues-stars-star-clusters-galaxies/

As the Earth Turns – Tour of the Night Sky – Aprilt 4 2014 9PM EDT

When planning your observing session , start with the things that are going to set first – Westward HO! The ECU view of the celestial sphere shows the sky centered on the Southern Meridian,You can see this on your planisphere. But your planisphere does not show the planets because they change from year to year. ECU can program the planets in…

Celestial Wanderers: Planets and Comets

• Jupiter, setting
• Mars Rising
• Comet (if there is a bright one…)

Night Sky West on April 4 2014 –Late Winter, early Spring Clusters

Night Sky South in April: Galaxies and Globular Clusters