Neptune – This Week & Next

Robert Conrad, our Observing Chair, posted on Facebook about a close conjunction of Neptune with the 4.2 magnitude star Phi Aquarii in Aquarius. The pair will be less than 15 arc-seconds apart on Thursday, Sept 6th – that is about a third of Jupiter’s apparent size at opposition – so the pair will appear practically on top of each other.

Neptune Storms

The Great Dark Spot of Neptune at the top accompanied by “Dark Spot 2” further south. Image credit: NASA/Voyager 2 Team

But then just after midnight on Monday, Sept 9th (technically, it will be Tuesday at 00:07:12 am), Neptune reaches opposition when it is directly opposite the Sun as viewed from the Earth. Neptune will have moved slightly to the west of Phi Aquarii by then but is still close – within 10 arc=minutes.

If you haven’t seen Neptune then this is a great opportunity. Neptune is not visible to the naked-eye as its magnitude of 7.8 is well past the limit for naked-eye observations. You may get a glimpse of it using steady-supported binoculars but a 200x view through a 150 mm or larger telescope is required to resolve it into a disk. Either way, the 4.2 magnitude star Phi Aquarii is a good guide. AAVSO charts are on Robert’s post at:

Even better is to observe Neptune over several nights and notice its motion relative to Phi Aquarii. Neptune’s orbital period of 164.6 years makes it move slowly across the sky, it will still be together with Phi Aquarri in a one degree field of view on Oct 1st, 2019.

Recording the relative positions over several nights lets you avoids Galileo’s missed opportunity – there is evidence that Galileo observed Neptune on January 6th, 1613, and again on January 27, 1613 and noted a slight discrepancy in its position versus the background stars. However, there is no record that he made further observations and he likely thought it to be a fixed blue star rather than a planet.

Credit for Neptune’s discovery goes to Britain’s John Couch Adams and France’s Urbain Le Verrier who had worked out the position of a theoreticl 8th planet independently based on perturbations in the observed orbit of Uranus. Le Verrier’s analysis predicted the new planet’s location to with one degree of where it was observed by J. G. Galle and H. L. d’Arrest, staff astronomers at the Berlin Observatory, in 1846.

Neptune is a gas giant, like its near twin Uranus: it has more mass than Uranus but is slightly smaller because its greater mass cause more gravitational compression of its atmosphere. The methane in Neptune’s upper atmosphere absorbs the red light from the Sun but reflects the blue light from the Sun back into space. This is why Neptune appears blue. Neptune has the strongest winds of any planet in our solar system with wind speeds reaching 2,000 km/h, three time stronger than Jupiter’s. It has several large dark spots with the largest known as the Great Dark Spot – similar to the hurricane-like storms and the Great Red Spot on Jupiter.

Good August Window to #MeasureTheSkyBC

Looking for Stars with the Loss of the Night App.
Image credit: Christopher Kyba, CC BY-NC 4.0

August 22nd to 31st are great dates to help with our #MeasureTheSkyBC campaign to measure light pollution.

It’s easy – all you need is your phone & your eyes!

And… get a chance to win a prize by sending us an email at [email protected] that you did it. This month, we are giving away a copy of the RASC book “Explore the Universe Guide” and free registration to the Lightning Lake Star Gazer’s Package at Manning Park’s Dark Sky Astronomy Weekend, on October 18-20 & 25-27, 2019.

Here is how to participate:

Loss of the Nigh App Logo
  • Install the LOSS of the Night app from the Apple App store or the Google Play store.
  • Start the app and enter some basic user information in the user data section such as your age, whether you wear glasses/contacts, and your observing experience.
  • Go outside on a clear night. Try to pick a location where you can see a large part of the sky and that is away from bright lights. Ideally, pick a time after 10:00 pm when the sun is well below the horizon (after the end of astronomical twilight).
  • Follow the instructions in the app to start measuring stars.
Loss of the Night app Screenshot  with direction arrow
Follow the arrow to find a target star.

Using the app is a fun, video-game like experience – great for kids. It works by helping you find target stars and then asking if the star is visible with your eyes. There is a demo mode so you can even try it out during the day. The app does not need internet (after it is installed) so you can use it when camping or out at a remote location.

Start by aiming your phone/tablet at the sky. The app displays a star field over-laid with a circle and an arrow.

Move your phone/tablet in the direction of the arrow. Go slowly and turn your whole body as necessary to follow the arrow.

Is the target star visible with your eyes?

When you locate the target star, a large orange circle is displayed, a smaller flashing yellow circle appears around the target star, and the display freezes.

Now you can lower your phone/tablet and look to see if the target star is visible with your eyes. Finish with this target by clicking the appropriate button.

Repeat on 8 target stars to get a good measure of the light pollution at your location. Expect some target stars to be easily visible, some barely visible, and some not visible, as the app tries to narrow down what you can see at your location.

After you’ve finished your measurement, the app will display your “limiting magnitude” which can be used as a measure of light pollution. Your data can be sent anonymously to a global database of light pollution measurements. You can see your measurement on a map, track changes over time, and compare it to other observations from around the world at

Don’t forget to send an email to [email protected] for a chance to win a prize – please include your location and limiting magnitude in the email if possible.

Milky Way from Cascade Lookout at Manning Park

Plate Solving 1 -What am I looking At?

If you are familiar with the constellations then you will quickly recognize the distinctive W-pattern in the image below and identify it as an image of the constellation Cassiopeia.

Image Credit John Sanford –

Now how about the image below?


This one is harder to identify but some amazing software software has become more accessible to amateur astronomers in the last few years that makes identifying images a breeze. Plate Solving software uses pattern matching techniques to match an image of the sky with star catalogs to determine the stars and other objects that appear in the image.

The popular web app plate solver, (, can be used without installing any software – just upload an image and after a few minutes displays results like the following.

It is a bit of a jumble of overlapping star labels but near the center you can see that the Messier cluster M103 has been identified. also displays a wider view of the area around the image and the deep-key objects that it found in the image. In this case, we can see that the image is an area near Casseopeia that contains M103.

The term “Plate Solving” is historical and refers to the large photographic glass plates that were used prior to the development of photographic film. Plates continued to be used in astronomy until the 1990s because they were superior to film for research-quality imaging – they were extremely stable and less likely to bend or distort.

Plate solving did not originate with the advent of computers, it was done manually by humans and often by women. The Harvard Computers were a team of women whose work included classifying stars by comparing the photographs to known catalogs. Many significant scientific contributions were made by these women’s subsequent analysis, classification, and processing of the astronomical data in the plates:

  • Annie Jump Cannon developed a stellar classification system using the strength of absorption lines and categorized stars into the now-familiar spectral classes O, B, A, F, G, K, M,
  • Antonia Maury discerned in the spectra a way to assess the relative sizes of stars, and
  • Henrietta Leavitt showed how the cyclic changes of certain variable stars could serve as distance markers in space.

Plate solving software is available in other package in addition to and a follow-up article will cover other packages and the uses of plate solving by amateur astronomers.

Fireflies, the Stars, and Dark Skies

The flashes of fireflies on a warm summer night create enchanting light shows. Fireflies exist on every continent, in North America they are most common in Eastern Canada and the United States. Ten species of fireflies in five genera have been recorded in British Columbia but adults of only two species produce flashed bioluminescent signals. Fireflies have captured the human imagination for centuries and have frequently been the focus of art, literature, and cultural traditions.

A jungle full of fireflies, few trees like this were really filled up with hundreds of fireflies in small area. They displayed a synchronized light pattern a mating time where males put up the light show to attract females. The moonlit forest added the fill light while the stars in background completed the frame to witness this most dramatic scene – Credit: Abhijit Juvekarf, Malshej, Ghat, India.7 Jun 2014.

Here come real stars to fill the upper skies,
And here on earth come emulating flies,
That though they never equal stars in size,
(And they were never really stars at heart)
Achieve at times a very star-like start.
Only, of course, they can’t sustain the part.

Fireflies in the Garden by Robert Frost

This year’s World Firefly Day was on July 6-7, 2019 and the theme this year was “Fireflies need dark nights.” There is growing evidence that suggests light pollution contributes to the decline of firefly populations across the globe. Fireflies emit light to attract males, communicate, and defend territory. Scientists have found that light pollution reduces flashing activities in a fireflies.

The most important step to take to protect nocturnal species like fireflies from light pollution is to follow responsible lighting practices that reduce or eliminate unnecessary outdoor lighting. You can also fight light pollution by helping #MeasureTheSkyBC with you smart phone or tablet:

  1. Download the Lost of The Night app from the Apple App Store or Google Play Store 
  2. Measure the sky glow at your location using the app on a night when the Moon is below the horizon – the dates Aug 22 – Aug 31 around the next new Moon are a great time to make measurements.
  3. Submit your measurement and send an email to [email protected] for a chance to win prizes. 

Another cultural connection between fireflies and space is the 2002-2003 TV serfies “Firefly” that follows the the adventures of the renegade crew of Serenity, a “Firefly-class” spaceship. 

Solar Cycle 25: It’s Alive

Solar Cycle 25 is coming to life. For the second time this month, sunspots belong to Solar Cycle 25 have been identified. A sunspot, numbered AR2744, emerged in the Sun’s southern hemisphere on July 8th, 2019 and has been identified as being part of Solar Cycle 25 according to

The solar cycle is a cycle of low to high magnetic activity that the Sun goes through approximately every 11 years. The sun is currently in a period of minimum magnetic activity at the end of Solar Cycle 24. The appearance of sunspot AR2744 heralds the possible start of Solar Cycle 25.

How is AR2744 indentified as being part of Solar Cycle 25?

A key piece of evidence relies on identifying the polarity of the magnetic fields of sunspots. Sunspots generally group together in pairs to form the poles of solar magnets as if a giant horseshoe magnet was placed under the Sun’s surface.

Sunspots often come in pairs with opposite polarity as if there was a horseshoe magnetic under the solar surface. Image credit: Windows to the Universe artwork by Randy Russell using an image from NASA’s TRACE.

One sunspot of each pair has a positive (“+” or “north”) polarity where the magnetic field is directed outward. The other spot in the pair has the opposite negative polarity (“-” or “south”) where the magnetic field is directed inward. The polarity of sunspots is highlighted in magnetogram images which show the strength of magnetic fields and their polarity. The image below is a magnetogram image of the area around AR2744 where areas with “+” polarity appear as green while areas of “-” polarity appear as red/orange.

A magnetogram image of solar surface around AR2744. Credit: NASA/SDO

Sunspot pairs are usually oriented parallel to the Sun’s equator so a sunspot pair can be classified as either:

  • “+/-” as in the image above, or
  • the opposite orientation “-/+”, as if the horseshoe magnet was rotated 180 degrees.

Sunspots in the Sun’s southern hemisphere from the old Solar Cycle 24 have a -/+ polarity. AR2744 appeared in the southern hemisphere but its polarity, as seen in the above image is “+/-“, making it a part of Solar Cycle 25. This reasoning is based on G.H. Hale’s observations in the first decade of the 20th century:

  • The same polarity pattern is seen in each solar hemisphere. For example, all cycle 24 sunspots in the southern hemisphere have the same “-/+” polarity.
  • Opposite polarity pattern are seen in north vs southern hemisphere. So all cycle 24 sunspots in the northern hemisphere have “+/-” polarity.
  • Polarity patterns reverse in each subsequent solar cycle. The “-/+” polarity of cycle 24 southern spots flips to “+/-” for cycle 25.

It is common for sunspots belonging to both cycles to appear during the transition from one cycle to the next so we will have to keep an eye out for more spots belonging to cycle 25.

10 More Moons for Jupiter

Sometimes stuff gets in the way when you are looking for
faint Kuiper belt objects near the edge of the solar system. That is what happened to a team of scientists using the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory in Chile. The huge 520-megapixel camera attached to the telescope also had Jupiter in its view leading to the discovery of 10 new moons for the largest planet in the solar system.


An additional year of observations verified the orbits of the moons and their status was confirmed by the International Astronomical Union on July 17th, 2019.

The moons are all less than 3 km in diameter and orbit Jupiter much further out than the large primary moons. The moons of Jupiter have been classified into a few groups:

  • The inner group of primary or Galilean moons (purple),
  • The prograde group that orbit Jupiter in the same direction as Jupiter’s rotation (blue), and
  • The retrograde group that orbit in the opposite direction to Jupiter’s rotation (red).

The newly discovered moons mostly fall into the above groups with 2 in the prograde group and 7 in retrograde group.

One outlier orbits in the same direction as Jupiter’s rotation but is located within the retrograde group. This outlier has tentatively been named “Valetudo” after Jupiter’s great-granddaughter. Its orbit with the retrograde group is unstable and a collision is likely at some point.

The new discovery brings Jupiter’s total up to 79 moons – the most of any planet in our solar system. Four moons of Jupiter were discovered by Galileo: Io, Europa, Ganymede, and Callisto. They are among the largest satellites in the Solar System and are easily visible in a small telescope or even binoculars (if they are supported or held steady enough).

Image of the Galilean Moons through a 100 mm refractor from Dec 2013. Image Credit: RASC Vancouver member, Ken Jackson

Jupiter is currently located about 20 degrees above the horizon, due south, at 10:00 pm PDT. Come out to Starry Nights at SFU’s Burnaby Campus on Friday, July 26th from 09:00 pm to midnight to get your own look at the Galilean moons (weather permitting) – Io slips in behind Jupiter at 09:30 pm but Europa, Ganymede, and Callisto will appear as tiny points of light with Europa on one side and Ganymede & Callisto lined up on the other side.

Celebrate the 50th Anniversary of the Apollo 11 Landing

Join us for a gathering with light snacks, door prizes, moon talks and short films followed by observing Jupiter and Saturn at the Trottier Observatory.

Saturday, July 20, 2019, 7:30 PM to Midnight

  • Celebration and Talks: 07:30pm to 10:00pm in Room SWH 10081 (Saywell Hall). Limited to 150 people.
  • Observing at the Trottier Observatory: 10:00pm to midnight (weather permitting)

Simon Fraser University, Burnaby Campus – find us on a map logo

RSVP and View the event on meetup

Admittance to the observatory is on a first-come, first-served basis. For a summary of our Observatory House Rules and Starry Night Etiquette, please visit:

Speakers: Ted Stroman and Leigh Cummings

Abstract: On October 4th, 1957, the USSR launched the first successful orbital satellite into space. By the end of the 1960s, only 13 years later, the USA successfully landed 2 men on the Moon. Ted Stroman is an expert on the history of the Apollo program that brought that to be. Leigh Cummings has been trying to keep up with the developments in the effort to return to the Moon by the next decade. We hope to give an entertaining and eye-opening picture of where and how we have been to the Moon and where and how we might go on.

One of the interesting Apollo facts you will learn at the talk is that the first Apollo 11 “feet” to touch the Moon were Canadian! The four landing gear system “legs” (or “struts”) on the Apollo Lunar Module descent stages were built by the Canadian company  Heroux-Devtek, based in Quebec. These landing legs were constructed of a light-weight aluminum and compressible honeycomb design to aid in shock absorption.

The first Apollo 11 feet to actually touch the surface of the moon – were made in Montreal. Image credit: NASA

Neil Armstrong landed so gently that the legs did not compress on impact leaving the Lunar Module’s ladder positioned quite high above the surface.

Join us on July 20th to learn more.

High Tides during the Eclipse

A visitor to our Canada Day table noticed that the tide seem very low in False Creek and wondered if it had any connection to the Total Solar Eclipse on July 2nd in South America.

The answer is yes. A solar eclipse must happen at new Moon when the the Moon is lined up directly between the Sun and the Earth.

Image Credit: Penn State Astronomy & Astrophysics

Tides are mostly caused by the gravity of the Moon as it pulls the water on the near-side away from the Earth and pulls the Earth away from the water on the far side. With the Sun aligned with the Moon during an eclipse – the Sun is also pulling in the same direction and so the tides are larger.

Total solar eclipses are awesome events to see but not that special for tides. The same alignment and high tides occur at every new Moon regardless of whether or not there is an eclipse. Such high tides have been give the name “spring tide” (technically, spring tides also include the high tides that occur when the Moon is full)..

Other factors cause the highest tides which are colloquially known as “King Tides”. The orbit of the Moon around the Earth, and the Earth around the Sun are not perfectly circular and tides are larger when

  • The Moon is closest to the Earth – the Moon is at perigee
  • The Earth is closest to the Sun – the Earth is at perihelion

Back in Sept 2015, the above factors plus others combined to give extreme tides that will not be matched again until 2034! Read more about the Extreme Tides September 28 in 2015.

Solar Minimum Ha Fun on Canada Day

You might think there is not much to see on the Sun as experts predict a long, deep solar minimum in 2019. But you can try to prove them wrong by observing the sun at the Canada Day celebration in Maple Ridge‘s Memorial Peace Park from 12 pm to 6 pm on Monday, July 1st, 2019.

RASC Vancouver will have several special hydrogen-alpha (Ha) telescopes setup for the public to safely observe solar features such as flares, prominences, sunspots, and filaments. Hydrogen-alpha (Ha) telescopes use special filters that block almost all the light from the sun except for a narrow band of red light emitted when hydrogen is energized in sun’s chromosphere. Many think that Ha’s greatest highlights are the prominences shot out from the sun’s limb, and large prominences can occur even during a solar minimum.

If the weather and the sun cooperate then you will be able to see some on Canada Day. In the the mean time, take a look at the pictures below, taken by amateur astronomers, to see what solar features can look like in Ha.

Full Disc Image with Prominences and Filaments from June 4th 2019 . Image Credit:
Fountain Prominence Animation on May 18th, 2019. Image Credit:
Active Region AR2741 from May 15th, 2019. Image Credit:
Large Solar Prominence from Coquitlam on Oct 16th, 2018. Image Credit: Ken Jackson