Hello Everyday Astronomer,
Welcome to Observations. This is the “Our Wide Sky Astronomy Update” regenerated into something new. I warned you about this in the last update 🙂.
A few times a month you’ll get this in your in-box. It will be an astronomy update, but it will also will be more risky, more controversial, more diverse in topics, and more fun. I will put more of me into it and I hope that will make it more interesting for you.
There will always be some astronomy. Always.
Thanks for being part of this new newsletter. I’m starting off with a dire subject, something literally very close to home for me.
Please stick with me for a few issues. Over the next few issues I’ll be ironing out the bumps. I hope you’ll let me know what you think.
Founder and Host of Everyday Astronomers.
#climateemergency. It’s personal.
When I was a teenager I won an art prize for a poster I created. It was lots of tall chimneys with billowing smoke and in big block letters it said “Stop Pollution Now!”. I don’t know what became of that poster but it has stuck with me as a memory for a very long time.
Now the fight has higher stakes, and is manifesting once more as air pollution.
Over the past few weeks Eastern Australia has been burning. We always get bushfires. From December to March. With one devastating fire that takes lives and many properties and even towns, every few seasons.
But now it is a lot worse. We have had fires here since October. Already this fire season at least 2.7m hectares (6.7m acres) of land and bush has burned, including national parks and world heritage areas and 720 houses. This is about the size of Haiti and there are nearly 100 countries with area smaller than this. And December has just beginning.
The smoke from the fires burning to the west of Sydney have oppressed us for weeks. During the worst of it I wear a facemask at work to protect my lungs. Yesterday air quality in Sydney reached 11 times hazardous levels.
This is what the Moon looked like on December 5 from by backyard. It has looked the same most nights since. No processing, the colour courtesy of bushfire smoke:
Walking home from work one day last week I was seeing ash and burned leaves fall from the sky. I collected them just from my backyard the next day. I live 70km (43.5miles) from the nearest fireground.
This is a manifestation of climate change. It’s happening year after year. A decade ago this kind of bushfire activity was an anomaly. We now have higher than average temperatures, record breaking temperatures and average temperatures, and a drought that is worse than anyone has seen. This is not normal, and it is devastating to our forests, our wildlife and our communities. And it is real and personal. We feel it, breath it, smell it.
When people are losing their homes and their livelihoods, when fire volunteers are collapsing with exhaustion, it doesn’t seem right to complain that I can’t see the stars due to bushfire smoke. As someone whose house is far from risk, it also doesn’t seem right to stay quiet.
I’m a positive person, but this Climate Emergency is the most anxious I’ve been about things affecting humanity. I was growing up during the cold war with threat of nuclear annihilation, and I had a lot more of my future to worry about. This feels worse.
I do what I can to reduce my carbon emissions and I vote like the future depends on it. My contribution is tiny, but is it something within my control. It is only governments and markets that can make the real structural change needed to keep us safe. I need to do more to try to make my elected officials understand. Perpetual lack of action is disheartening.
I’m not sure that I should have started my new newsletter with doom. Don’t worry, readers. My focus is on astronomy, but because of the terrible air quality in Sydney, this has been front and centre, and in my lungs and my eyes. I can’t be silent about it.
It’s solstice time. The days are longest or shortest, depending on where you live. Here our days are long and hot. In the northern hemisphere you are in the middle of winter.
The official solstice is Sunday, 22 December 2019 at 04:19 UTC. This is the moment the path of the Sun meets the latitude of the tropic of Capricorn. At this time at latitude 23.44°south the shadows at noon will be smallest and the day will be the longest day of the year.
It’s interesting to look at daylight hours around the world. Reykjavik in Iceland has 4:41 hours of daylight and Ushuaia at the southern end of South America has 17:20 hours. In Sydney we get 14:24:46 hours of daylight.
How many hours of daylight can you expect at your location? I used Time and Date to get the figures above.
Did you know that the summer solstice is referred to as the Estival Solstice and the winter solstice is the Hibernal Solstice? These terms depend on the hemisphere for context. You can also use the terms northern solstice and southern solstice for clarity.
What’s up in the sky right now?
Venus will be a bright jewel in our western sky until June 2020. I love this season of Venus. It is so easy to pop outside and find the brightest small thing in the sky. Over the coming months Venus will be very busy:
Venus will have several encounters with the New or Waxing crescent Moon. Venus, a slim Moon and Earthshine make a beautiful sight after sunset. Here are some dates:
January 28th. Venus will be 4.4° from the New Moon.
May 23rd. Venus will be 3.7° from the New Moon
June 19th Venus 0.7° from the Moon. This is really close!
On March 24 Venus will be at “Greatest Elongation”. This means it is, from our perspective, as far from the Sun as it gets in the western sky. It will be bright and you’ll see a half phase of Venus if you have a chance to look through a telescope.
Watch Venus through a telescope over the coming months and you will see it change shape as it approaches Greatest Elongation and then beyond.