Evidence of human fascination with the sky goes back as far as recorded history. Beginning from the Babylonian era as far back as 3000BC to the Chinese who were undoubtedly the world’s most astute skywatchers by around 400BC, documented stories of heavenly bodies attest to this. But the Greeks even went as far as relating their gods to heavenly bodies in the sky, Zeus the god of the sky (Jupiter), for instance. The sky has also captured the imaginations of poets and philosophers for centuries as one of life’s mysteries.
Today, we view the sky with ease and with un-diminished enthusiasm as ever, largely due to advances in technology. Now, what has led us into understanding the sky that is unfathomably vast and used to be mysteriously incomprehensible? Optics and related scientific instruments, of course! But the invention of the telescope in the early seventeen century, for instance, was pivotal to our understanding of what the heavens hold.
In 1609, the mathematician and astronomer, Galileo Galilei with his modified telescope, earlier invented by Hans Lippershey, turned towards the heavens and made several startling observations, such as Jupiter’s four moons. Other early discoveries were that Venus had phases; as well as the rocky mountains on the moon and sunspots, which were inaccessible to the unaided eye.
Enter Edwin Hubble, who in 1924, not only demonstrated with a 100-inch telescope on Mount Wilson in Southern California, that other galaxies exist apart from our own the Milky Way, but they also are moving away from us and each other at an increasing speed.
In other words, he proved that the universe itself has been expanding, which is known as the Hubble Constant, since it exploded 13.7 billion years ago from an inflationary process that led to the Big Bang. That changed our perception and view of the universe forever. To his credit, NASA’s Spitzer space telescope measurements confirmed the Hubble Constant in 2012. The space telescope, Hubble that was carried into orbit by a Space Shuttle in 1990 and remains in operation till date and is now sending never- before- seen images of the universe, is named after him.
In all these advances in space exploration, one would legitimately ask, what is Africa’s stand? The good news is that Africa is on the map and in the club as well. South Africa and Australia are now co-hosting the most Advanced Scientific Project in the world – the Square Kilometer Array Telescope, (SKA).
The SKA is a radio telescope that is expected to work on a range of frequencies that will make it tens of folds more sensitive than other existing radio astronomy instruments. It will cost about 1.5billion euros to construct, and already, many countries are ready to pay the bill in the hope of returns on their investment in the future. When completed around the year 2027 it is reckoned to generate astronomical data deluge – the data collected by the SKA in a 24-hour period would take nearly two million years to playback on an iPod or the equivalent of information contained in the Library of Congress.
Back home here in Nigeria, one wonders what our investment in this seemingly future technology is? Are our schools equipped to harness this field of astronomy? Is our government making any efforts to catch up? Or are we going to continue, as usual, to keep producing geography and physics graduates who have hardly been in contact with an ordinary telescope that had been around for more than four hundred years? Because in the very near future, asteroid mining is going to be the leading venture in the search for precious stones and minerals, and the technology to that is already available.
Now back to the celestial event of a lifetime coming up on December 21, 2020, the planetary conjunction of the giant planets Jupiter and Saturn.
Conjunction, planetary alignment, occurs when two objects are near each other in the sky to our vantage position on Earth. Jupiter and Saturn will come so close to about 0.1 degrees apart on that evening to give us once a lifetime celestial show. For this: there’s an enormous excitement going on among astronomers and skywatchers around the world right now. The last time such an event happened was almost 800 years ago and will not occur until 380 years to come, precisely in the year 2400. Where to look on that night?
According to NASA, the great conjunction will be visible shortly after sunset, low in the southwestern sky – wishing you clear skies, weather permitting!