From a planetary point of view, humanity has stayed at home every year since 1972 (the last time humans left low Earth orbit to visit the Moon was on the Apollo 17 mission). If instead, you do count low Earth orbit as “leaving home”, we’ve been stepping out the door since 1961, and have maintained a continuous presence in space since the year 2000.
Despite the challenges to most industries faced during the last 12 months, the space industry has been pressing on. To name just a few events, 2020 has been an exciting year in spaceflight: NASA launched the Perseverance Mars Rover - the next step in the pioneering Mars sample return mission; and Spacex became the first private company to deliver humans to the International Space Station.
From an astronomical perspective, watching from home we have also been treated with some excellent spectacles, including the comet NEOWISE’s visit to the night sky in July; and more recently in December the great conjunction of Saturn and Jupiter.
On a more personal level, I’ve found astronomy and space photography a welcome retreat from the digital world where we now spend more and more of our time. As a quick wrap-up of the year, I wanted to share a handful of photos I’ve taken in 2020, to prove just how much you can see from your back garden.
February 27th - Orion
A good winter sunset is quite a magical event. On a commute back from work in late February I was treated to a particularly clear one. As soon as I got home I raced back out again, camera bag over my shoulder, heading for a little coppice of woodland nearby to capture the end of the spectacle.
By the time I set up my tripod the sun had well and truly set, but I was able to line up some shots of the waxing crescent moon and the first stars coming out. Above is my favourite exposure of the set, a scattering of stars seen through the a gap in the trees.
Later when editing, I realised I had inadvertently captured the constellation Orion, which in the Northern Hemisphere is visible in the evening winter sky. The three bright stars in a line in the middle of the frame is Orion’s belt.
April 22nd - Starlink
In mid April, while coming to terms with the bitter realities of life in lockdown, those of us in Northern Europe were offered a rare chance to witness some innovative satellite deployment with the naked eye.
While the Spacex Falcon 9 rocket carrying the 60 Starlink satellites into orbit was launched from Cape Kennedy, Florida, I was able to take this photo of one of them passing over my back garden in England. It’s not often that so many satellites are launched in one go, meaning watching the procession marching across the night sky is a rather unique experience.
In fact it’s very lucky we even got to see them at all. Not to mention the fortunate weather, had the satellites been launched at a different time of year, their flight path to orbit would not have passed over Northern Europe. Had they been launched at a different time of day, they wouldn’t have caught the Sun’s light in such away to illuminate them so vividly against the night sky.
The satellites themselves were put into orbit to join the Starlink constellation, a network of 955 communications satellites designed to disperse themselves in low Earth orbit. When complete, the constellation of 12,000 satellites will enable satellite internet connection from across the globe.
December 21st - Jupiter & Saturn
Closing off the year in style, during December the positions of the planets aligned in such a way to bring Jupiter and Saturn extremely close together when seen from Earth. The length of Jupiter and Saturn’s orbits mean that these conjunctions don’t happen too often (a year on Saturn lasts 10,759 days). This particular conjunction was deemed a “Great Conjunction” due to just how close the planets would appear in the night sky - less than a quarter of the Moon’s apparent diameter.
The orbits of Earth, Jupiter, and Saturn can be visualised like three spinning plates spinning stacked on top of each other: the Earth, which is quite close to the Sun, being the smallest of the three, and Saturn, furthest from the Sun, being the largest. The plates don’t quite sit on each other flat and wobble as they rotate. While the plates complete a rotation rather quickly, it takes a lucky combination of events for all three to line up so closely.
In the Northern Hemisphere, the planets were visible in the south-western sky for a couple of hours following sunset. While driving out to a suitable vantage point, the sky seemed thick with clouds and I wasn’t particularly hopeful at getting to see any of the action. Fortunately, the strong wind kept the sky-scape moving and through a gap in the clouds I was able to take this shot.
The planets themselves are hard to see in the wide view, but are can be seen as faint dots on the top line of a cloud roughly a quarter of the frame in from the left, and about halfway up from the bottom. Below is a zoomed-in view. Jupiter, being closer to Earth and larger in size, is the brighter dot, with Saturn fainter to the upper left.
Looking ahead to 2021, there’s plenty to be excited about. As well as a couple more conjunctions and a total solar eclipse (sadly only visible from Antarctica), perhaps the most significant event is the launch of the highly-anticipated James Web Space Telescope (JWST) in October.
The JWST is the spiritual successor to the Hubble Space Telescope, and is much more complex in both its technology and mission scope. It will be launched on an Arianne 5 rocket, and will streak past low-Earth orbit into solar orbit. Without the protection of the Earth, it needs to bring its own solar shade - which will take 3 days to unfold while it heads to its target orbit. With its mirrors optimised for low-energy infrared light, the JWST will peer through the murky, dusty expanses of interstellar space to observe some of the oldest and most distance objects in the observable universe.
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