Start Observing Mars Now

(or wait 15 Years)

Start observing Mars – Now, Today, or as soon as we get a clear night after the wildfire smoke clears out. The upcoming close approach and opposition of Mars, on Oct 9th and 13th, will likely provide the best views of Mars for the next 15 years as Mars will either be smaller or at a lower altitude during the next 6 oppositions. Plus, while the Southern Polar Cap is prominent now, it is melting and may disappear from view completely as we move later into October.

Location of Mars on Oct 13 2020 from Vancouver at 10:00 pm
Stellarium chart showing the location of Mars at 10:00 pm PDT on Oct 13, 2020 from Vancouver, BC – in the south-east skies, about 30° above the horizon.

Mars is easy to spot using just your eyes as it is one of brightest objects in the sky (even rivaling Jupiter in brightness) and it has a distinctive red-orange colour. It will becomes easier to see without staying up too late as it rises in the East earlier and earlier: at 8: 50 pm on Sept 13, 6:30 pm on Oct 13th, and 03:07 pm on Nov 13th. In theory the best views come closer to midnight when Mars is at its highest, due South and crossing the meridian. But the face of Mars changes as it rotates so it is said that the best time to view Mars is “all night” to watch different surface features make an appearance. 

What You Can See

A telescope is required to see any surface details even when Mars is at its biggest and brightest – Mars’ maximum size in this apparition is just 22.6 arc-seconds – that is small. By comparison, the full moon is more than 80 times larger.

Mars will appear small as shown in this simulated 0.22° field of view and 225X magnification that I obtain with this setup: Skywatcher ED 100 mm f/9 refractor, Vixen 10mm SLV eyepiece & 2.5x Powermate/Barlow.

But even relatively small telescopes (60 to 100 mm) do reveal the major features: the polar caps, lighter areas of rust-coloured dust, and darker areas of exposed volcanic rock. Larger scopes are capable of better resolution and showing more detail.

You’ll want to bump up the magnification, by using a longer focal length telescope or shorter focal length eyepiece, for example. The highest usable magnification depends on the seeing conditions and the aperture of your telescope. Generally, a magnification of 1 or 2 times the aperture in mm works well on nights of good seeing. For example, if you have a 100 mm telescope, try 100X to 200X. If you have a 200 mm scope, try 200X to 400X. However the maximum magnification is usually limited by Earth’s atmosphere as any turbulence will blur the image. Magnifications above 400X may not be realistic no matter how large the telescope.

Simulated magnified view of surface details through a 200 mm (8 inch) Schmidt-Cass telescope. Image credit: generated with CalSKY.

Simple eyepiece designs with fewer glass elements and a narrow field of view can work well. Eyepieces with a shorter focal length will provide a higher magnification. A good 2x or 3x Barlow or Powermate lens can be useful for increasing the image size with your set of eyepieces.

The Changing Face

Mars rotates on its axis at almost the same rate as Earth giving it a day/night cycle that lasts 24 hours, 39 minutes, and 35 seconds. That is good for observing for two reasons. First, you can see different surface features throughout a single night. If you start observing at 08:00 pm on Oct 13th with a dark feature like Syrtis Major located near the western limb then 4 hours later, at midnight, it will have travelled towards the center with the new feature Sinas Meridiani appearing in the west.

The second benefit is that you can observe at the same time on subsequent nights and see a new feature near the eastern limb before it rotates off the face about 40 mins later. The free program Stellarium displays a simulated view of the surface of Mars when you zoom-in enough and you can use it to visualize how features move as Mars rotates.

The changing face of Mars over several weeks near its opposition. Image credit: generated with Stellarium.

With the patience to observe over several weeks, this rotation makes it possible to see the full 360 degrees of the Martian globe.

Prominent Surface Features

The RASC Observer’s Handbook 2020 has a map of the major features on page 221 and there are plenty of others available online.

Image credit: Space Telescope Science Institute, Ann Feild Didyk and Graphics Dept.

Many maps show a view following a convention where “South is up” and remember that your view through your telescope may be inverted (common for reflectors like Dobsonians) or mirror flipped right-to-left (for refractor, compound, or Schmidt-Cass scopes). So check your orientation when identifying features.

The major features of the Martian surface (excluding the polar caps) following the “south is up” convention. Image Credit: Damian Peach/Sky and Telescope.

CalSKY or the online Mars Profiler from Sky & Telescope are useful tools for showing features visible at any observing site and any date/time. 

The polar caps are one of the most striking features. The Southern Polar Cap (SPC) is prominent at this time because it is just past the summer solstice in the Martian southern hemisphere. Summer in the south means that the south pole is tilted towards the Sun and, near opposition, also towards us on Earth. But don’t hesitate in having a look for it because the SPC is shrinking and will likely melt away completely during this apparition. It is getting a double whammy of summer heating and additional heating because Mars is at a position in its orbit that brings it relatively close to the Sun. The northern polar cap will not be visible but it is possible to see hazy clouds above the northern region. 

Other prominent regions on Mars are differentiated by brightness and colour with lighter areas of rust-colored dust, and darker areas of exposed volcanic rock. The lighter areas were thought to be continents so their names include “land” or “plain” such as Arabia Terra, Hellas Planitia, and Amazonis Planitia. The darker regions were thought to be seas or large patches of vegetation. Examples include Mare Erythraeum, Mare Acidalium and the striking Syrtis Major Planum. These dark regions may appear to change their size and shape over time. Early observers attributed the changes to rainfall or changes in vegetation but it turns out that these regions can be obscured by atmospheric dust or made brighter by the presence of clouds.

If you have a large telescope or the equipment and skill to photograph Mars then you may be able to identify some of the specific features described below.

Dust storms can appear as yellow-ish hazy areas. Local or regional dust storms are an interesting sight but large dust storms can ruin observing by obscuring features – a global dust storm during the last opposition in 2018 covered the entire planet!

Rotating globes from 2018 show a global dust storm completely obscuring the surface of Mars. Image Credit: NASA Hyperwall.

Blueish-white clouds, formed from water ice, may also be visible especially in photographs. Such clouds often appear near the equatorial regions, around the large volcanoes, close to the limb, or close to the northern polar region.

Syrtis Major Planum is one of the darkest regions on Mars. It was observed as early as 1659 by the astronomer Christiaan Huygens and was the first surface feature seen on another planet. It is now known to be a low relief shield volcano but was originally thought to be a shallow sea. The name “Syrtis Major” was chosen by Giovanni Schiaparelli during Mars’ close approach to Earth in 1877.

Olympus mons in the Tharsis Montes region is the largest volcano on Mars, and also the largest known volcanoe in the entire solar system. As a comparison, Olympus Mons is 25 km high and 624 km in diameter with a 80 km caldera at its summit while the largest volcano on Earth, Mauna Loa (10 km high and 120 km wide), is less than ½ the height, ¼ the diameter, and ¼ the height. Volcanoes can grow larger on Mars because of its lower gravity. Also, Mars’ crust remains stationary over a lava hot spot while on Earth crustal plates move above the hot spots spreading the lava among many volcanoes.

Comparison of Olympus Mons to large mountains on Earth. Image Credit:

Hellas Planitia is a large impact basin located in the southern hemisphere. Hellas can appear so bright (due to fog, surface ice, and clouds) that it is sometimes confused for the southern polar cap. It is likely to have been formed by an asteroid impact early in Mars’ history – about 4 billion years ago.

Valles Marineris is a large system of canyons that runs along the equator of Mars. It is the largest canyon system on Mars and is almost 5 times deeper than the Grand Canyon. The large canyon system was discovered in 1972 by NASA’s Mariner 9 spacecraft, the first satellite to orbit another planet.

Solis Lacus is also known as the “The Eye of Mars” because it is a dark circular feature surrounded by a light area, as is a pupil. Solis Lacus is known for the variability of its appearance, changing its size and shape when dust storms occur. Percival Lowell believed that it was the planetary capital of Mars due to the number of “canals” he claimed intersected at the region.

Surface features are apparent in this high Resolution image of Mars from September 11, 2020 taken with a Mewlon 250 telescope. South is up so the bright white patch at the top is the Southern Polar Cap. The large uniform light area at the right in the north is Amazonis Planitia. Clouds are visible around the Arsia Mons volcano in the Tharsis Montes region. More hazy bluish-white clouds appear on the left limb and above the Northern Polar region. Solis Lacus is faint just below center near the left limb. Image Credit: Damian Peach

Schiaparelli Crater is a large impact crater measuring approximately 460 km in diameter. It was named after Giovanni Schiaparelli, an Italian astronomer known for his observations of the Red Planet and his mistranslated term “canali”. In the book and movie, The Martian, Mark Watney, a stranded astronaut from the Ares 3 mission (the 3rd manned mission to Mars) makes a 3,000 km trek from Acidadia Plantia to Schiaparelli Crater to reach the landing site of Ares 4.

FInal Observing Tips

Mars only gives us a small view and it can be difficult to pick out the even tinier features on its surface, so here are some final tips:

  • Have patience. Observing is a learned skill that takes practice.
  • Pick a Night with steady air. Details are easier to spot when the air is steady and the stars aren’t twinkling too much.
  • Acclimatize Your Telescope. Bring your scope outside to acclimatize for at least 30-60 minutes before you plan to observe. This will help reduce the air currents inside your scope that degrade the image. Scopes with large mirrors or lenses, and those with closed tubes, take longer to acclimate.
  • Observe Frequently. Take advantage of the fact that Mars rotates slower than the Earth by extending your observing session for several hours on one night, or at the same time over several days to see all sides of the planet.
  • Relax and sit down. An old rule of thumb says that observing while comfortably seated is the equivalent of adding a couple extra inches of aperture. When you observe seated you are more relaxed and less shaky, and that pays off in terms of being able to see more detail.

Mars is one of the most interesting and rewarding objects in the solar system to observe and next few weeks provide the best opportunity in the next 15 years to view it.

Betelgeuse is BIG (and variable)

Betelgeuse is a bright star in the shoulder or armpit of the constellation Orion. It is easily visible in February and March from Vancouver around 10 pm, close to the southern Horizon.

Betelgeuse in Orion
Betelgeuse in the constellation Orion. Near the Southern Horizon from Coquitlam on Feb 18th, 2020

If you follow astronomy news at all you’ll have heard that Betelgeuse has recently been dimming. Betelgeuse is a variable star whose brightness is known to periodically rise and fall, but it’s recent dimming has been quite extraordinary. Especially exciting is speculation that Betelgeuse may explode as a brilliant supernova which would be visible even in daylight. Unfortunately the latest measurements have shown that Betelgeuse may be brightening again,

Less often reported is that Betelgeuse is BIG! – not too surprising given that it is classified as a red supergiant. So how big is it?

  • It is so big that its diameter is about 1300 times that of our sun.
  • It is so big that if placed at our Sun’s location, the outer edge of its photosphere would reach out to Jupiter.
  • It is so big that it was the first star to have its angular diameter measured. Stars are so far away that they appear as pinpoints of light whose angular diameter cannot be determined. But Betelgeuse was big enough that 100 years ago, in 1920, it was the prime candidate to submit to measurement of its angular diameter.
Betelgeuse Sun Size Comparison
Size Comparison of Betelgeuse and our Sun
Betelgeuse Overlay on Solar System
Betelgeuse overlaid on the Solar System
Image credit: ALMA (ESO/NAOJ/NRAO)/E. O’Gorman/P. Kervella

Michelson and Pease used the 2.5 m Hooker telescope at the Mount Wilson Observatory in California – the largest telescope in the world between 1917 and 1949 – but even it was not large enough to resolve the disk of Betelgeuse. Instead Michelson turned the telescope into an interferometer by attaching a framework with 4 six inch mirrors to the front of the telescope.

Michelson interferometer for measuring star diameters, attached to front of the 2.5m Hooker telescope.

The mirrors created 4 separate light paths of the star that combined, due to the wave nature of light, into an interference pattern.

Astronomical interferometers can produce higher resolution astronomical images than any other type of telescope – theoretically producing images with the angular resolution of a huge telescope with an aperture equal to the separation between the light paths. The separation between the mirrors of Michelson and Pease’s interferometer at Mount Wilson was about 20 feet (or 6 m) and this proved sufficient for them to measure the angular diameter of Betelgeuse as 0.047 arc-seconds.

Once you know the angular diameter, then if you also know the distance of the star, you can easily get its linear diameter in space. Michelson and Pease used several estimates of the distance to Betelgeuse available in 1920 to come up with a linear diameter of 386,000,000 km, somewhat smaller than more modern estimates. Using their 0.047 arc-seconds angular diameter with current estimates of the distance to Betelgeuse (about 724 light years) gives a linear diameter of 1.83 billion km — a truly colossal diameter, the equivalent of over 1,300 solar diameters!

Michelson and Pease published their results in the May 1921 edition of the Astrophysical Journal but a summary “Betelgeuse: How its Diameter was measured” appeared one month earlier in the April 1921 edition of the RASC Journal.

Betelgeuse is a peculiar star that is subjected to pulsation cycles that not only make is brightness vary but also make its size vary. Long-term monitoring by UC Berkeley’s Infrared Spatial Interferometer (ISI) on the top of Mt. Wilson show that Betelgeuse shrunk in diameter by more than 15% from 1993 to 2009. Recent images show that Betelgeuse has an asymmetric surface and appears to be shedding gas and dust at tremendous rates.

Asymmetric surface of Betelgeuse in Jan 2019
Astronomers used ESO’s Very Large Telescope to discovered a plume of gas ejected from Betelgeuse and a gigantic bubble that boils away on its surface. 
Image Credit: ALMA (ESO/NAOJ/NRAO)/E. O’Gorman/P. Kervella

Since Betelgeuse has a radius 1,300 times that of the Sun, it has a volume about 1.3 billion times larger than the Sun. But its mass is only about 8 – 20 times the Sun. This means the density of Betelgeuse is much, much lower than the Sun. The average density of the Sun is about 1.4 grams/cc – somewhat higher than the density of water. In contrast, the average density of Betelgeuse is just 12 billionths of a gram/cc. This is about a million times less dense than Earth’s atmosphere at sea level, or about the same as a vacuum found in an insulating Thermos bottle.

Feb. 18, 2011

Members: Leigh, Mark, Wayne, Oleg, Janeen & Clive

Arrive: 7:30 pm

Temp: 1 C

Weather clear with full moon.

Leigh opened dome and uncovered equipment in dome in anticipation of observing with LX200. The computer in the dome failed to boot. Tried several attempts with no results. Oleg gave it a try as well. We concluded that it seemed to be a problem with the hard drive. Unplugged and removed PC to take home and do further tests. Re-covered the telescope and other equipment and shut down power to dome.

Janeen brought her new Williams Optics 110mm Megrez APO. Very nice! Wayne took some photos of the Moon with his DSLR through Janeen’s new scope.

Unfortunately, Oleg had some difficulties with batteries and was unable to get his mount to work that night. He then lent his assistance to everyone else.

Clive and Janeen departed at 10:15pm

Wayne and Oleg departed at 10:30 pm

Mark and Leigh worked with Mark’s Tak and were able to get his Robo-Focus working properly. YEH! Continued working with Mark’s equipment taking photos with Mark’s DSLR.

Departed: 2:10 am

Temp: -2C

Earth Hour 2011: It's time to go beyond the hour

At 8.30 PM on Saturday 26 March 2011, lights will switch off around the globe for Earth Hour.

This year, when the lights go back on, we want you to think about what you can change in your daily life that will benefit the planet. To share your stories, thoughts and ideas with us and to get inspiration from what others are doing. So tell us what you’re going to do and we’ll tell the world.

Together our actions add up.

Visit Earth Hour Global Site at:

Earth Hour started in 2007 in Sydney, Australia when 2.2 million individuals and more than 2,000 businesses turned their lights off for one hour to take a stand against climate change. Only a year later and Earth Hour had become a global sustainability movement with more than 50 million people across 35 countries participating. Global landmarks such as the Sydney Harbour Bridge, CN Tower in Toronto, Golden Gate Bridge in San Francisco, and Rome’s Colosseum, all stood in darkness, as symbols of hope for a cause that grows more urgent by the hour.

In March 2009, hundreds of millions of people took part in the third Earth Hour. Over 4000 cities in 88 countries officially switched off to pledge their support for the planet, making Earth Hour 2009 the world’s largest global climate change initiative.

On Saturday 27 March, Earth Hour 2010 became the biggest Earth Hour ever. A record 128 countries and territories joined the global display of climate action. Iconic buildings and landmarks from Asia Pacific to Europe and Africa to the Americas switched off. People across the world from all walks of life turned off their lights and came together in celebration and contemplation of the one thing we all have in common – our planet.

Earth Hour 2011 will take place on Saturday 26 March at 8.30PM (local time). This Earth Hour we want you to go beyond the hour, so after the lights go back on think about what else you can do to make a difference. Together our actions add up.

A chance to address LPA issues with BC Hydro at an open house

Attention All LPAer’s! – Here’s our chance to shine, down, not up!

gastown clock at night

BC Hydro wants to hear from you about how we set the course for a Clean Energy Future. To add your voice, attend a public open house in a community near you. Registration is not required for these events.

Here is our chance to ask BC Hydro what they are doing about LPA issues on a province-wide scale.   Maybe even show them a photo or two!   Ask some questions.

This event will occur in Vancouver  on Tuesday, March 15, 2011 at 6:00 – 9:00 p.m. at the  Simon Fraser Morris J. Wosk Centre for Dialogue.

Also at Abbotsford Wednesday,
March 16, 20116:00 – 9:00 p.m.Clearbrook Community Centre.

For full details, please visit:

We could ask them:

– What is being done to establish & enforce lower & even lighting levels?

– When will non full cut-off lights be stopped being sold?

– When will new lights replace obsolete non full cut-off fixtures (street / road, parking, yard etc)?

– What is their stand on light trespass, skyglow, and glare reduction & elimination.

This is an opportunity for having our voice heard, power reduce waste (saving all citizens money also), and preserve the night sky.

This information was provided by:

Maurice Sluka

Royal Astronomical Society of Canada Prince George Centre

Media Relations & Past President

Planetary Society (member)

International Dark Sky Association (member)

Correct Lighting – Up Close And Personal

correct lighting - up close and personal
correct lighting - up close and personal

Look closely at the way this light is designed.  Its a seal unit with no way for light to escape from the top.  In addition, its using low wattage flourescent light blub technology.

This light is a good trade-off between long life, aesthetics and practicality.  We can all learn a few things from the designer.


Correct Outdoor Lighting

Correct Outdoor Lighting

correct outdoor lighting
correct outdoor lighting

Kudos to the lighting designer for this building.

The lighting on the Davis County (Utah) Library is a model of correct outfoor lighting techniques. Nothing glares in your eyes, no light trespasses on to adjascent properites. It’s lit to appropriate levels. I tried to make sure that the image I saw on the camera LCD matched what I saw with my eyes. The only difference was that I could actually see the stars.

It’s not the number of photons, but where they are directed that makes effective lighting.