Sagittarius is the archer of the firmaments.
A sky pattern identified by the ancients, Sagittarius was one of second-century astronomer Ptomelmy’s 48 constellations. The Latin word for “archer,” the grouping is still one of the 88 significant constellations by modern standards.
We often represent Sagittarius as a centaur – half human, half horse – with a taut bow, ready to fire. As one gazes into the cosmos, the center of our galaxy sits in the westernmost portion of the constellation. In northern-hemisphere summer, the archer grabs a prominent spot in the night sky; though we cannot see it then, the location of the Sun during the December solstice lies directly in front of Sagittarius.
While our ancestors doubtlessly spent hundreds of hours staring at metaphorical arrows coming from the heavens, their odds of dealing with actual threats from the sky were extraordinarily slender. The last impact by an object over six miles in diameter occurred 66 million years ago at Chicxulub, likely knocking out the dinosaurs. Scientists estimate asteroids large enough to create a crater over a mile in diameter only hit the Earth approximately every 11,000 years. Even then, the odds that the event would impact any specific human would be slim. In fact, only one human in recorded history has been hit by a meteorite (miraculously, she lived!)
Today, we’re increasingly under threat of non-metaphoric, non-natural arrows from space.
As we accelerate into a modern rocket age, with an increasing number of nations and private companies sending ships away from the planet, what goes to space doesn’t always stay in space. We’ve explored a few of the instances in which rockets have posed a threat to life on Earth. Traditionally, most nations have been responsible stewards of their rockets. If they can’t keep them in space or make sure they burn up in the atmosphere upon reentry, they shepherd them toward The Spacecraft Cemetery, also known as Point Nemo, the world’s most remote oceanic point.
Not everyone is trustworthy, though. The two biggest transgressors in the past decade are China and SpaceX. Australia recently discovered this reality in a unique and frightening manner.
Mick Miners, a farmer in New South Wales, Australia, toured his farmland and noticed a dead tree in the distance. But something seemed odd about the tree. Miners decided to investigate.
Turns out, it wasn’t a tree, at all. It was a space arrow.
The picture above shows a piece of space junk that stuck straight into a tract of Australian farmland. It came hurtling from above with enough speed to pierce the planet.
An astrophysicist went to the location to check out the monolithic arrow.
When the expert examined the strange item, he determined it was a remnant of a SpaceX capsule.
The debris hit on July 9, but wasn’t discovered by Miners for several weeks. Since then, two other fragments appeared on land owned by neighbors.
Space junk has, to date, only intersected with one human. In 1997, a small piece landed on the shoulder of a woman in Oklahoma. That’s a far less impactful incident than the meteorite that hit a woman in 1954.
Don Pollaco, an astrophysics professor in the United Kingdom, asserted the chances of a human being injured by space waste is “almost zero.” He added, “I don’t think people need to be frightened, the likelihood of them getting hit is unbelievably small.”
We don’t need to be frightened? Did you see the giant space arrow stick in the Earth?
Unless the planet collectively develops a system to keep space arrows from raining through the atmosphere, the chances of danger will only increase in the coming years. Rocket numbers will certainly rise.
A study from the University of British Columbia believes there is a 10% chance that at least one person will die from space debris in the next decade. That probability is, thankfully, low.
The bad news is that number was probably 0% in the preceding decades. Zero to 10 is an infinite increase in likelihood, right math aficionados? Definitely a 0% chance for the arrows of Sagittarius to hit us!
Further Reading and Exploration
Space debris Australia: Piece of SpaceX capsule crashes to Earth in field – BBC
SpaceX capsule confirmed as source of space debris that crashed on farm in Australia – The Guardian
Unnecessary risks created by uncontrolled rocket reentries – Nature Astronomy