While we’re obsessing over Covid-19, maybe we should realize there are other threats to life on earth. Some of those threats are not even here—they’re from outer space. No, this is not science fiction—it’s science fact. There are genuine risks that don’t include UFOs and little green men.
The most obvious risk is the danger that we may be hit by a large asteroid. You know, like the one we think killed all the dinosaurs. In fact, The Guardian says space asteroids and satellite debris may be the greatest threat to life on earth.
On Thursday 25 July [last year], an asteroid 57-130 metres across missed our planet by just one-fifth of the distance to the moon. In astronomical terms, that’s a hair’s breadth. Had it hit us, the devastation would have been staggering.
But we’re not standing idly by.
Next year, Nasa will launch what all involved hope will be the most impactful space mission to date. The Double Asteroid Redirection Test (Dart) is designed to smash headlong into its target. It’s an attempt to deflect an asteroid as a test of what to do if we spot a similar space rock on a collision course with our planet.
Meanwhile, the European Space Agency plans a program called “Hera” that will investigate the aftermath of DART, to study the test, in order to develop a workable asteroid defense program.
Of course, as usual, we don’t have to wait for a crisis. We often cause our own. In this case, before we are hit by an asteroid, we’ll likely have numerous “attacks” by our own space junk. Space.com lists many examples. Here are a few:
The European Space Agency’s GOCE satellite fell to Earth on Nov. 10, 2013. . .The gravity-mapping GOCE satellite weighed about 1 ton and was about 17 feet long (5.3 meters). That’s pretty big, but much larger satellites have made uncontrolled re-entries over the years. . .
The 6.5-ton UARS satellite was 35 feet (10.7 m) long and 15 feet (4.5 m) wide. . .fell to Earth in September 2011. Researchers estimated that about 1,170 pounds (532 kilograms) of UARS’ 6.5-ton bulk likely survived re-entry. . .
On July 11, 1979, Skylab returned to Earth, burning up over the Indian Ocean and Western Australia. Some large chunks survived re-entry, making landfall southeast of Perth and elsewhere. Nobody was hurt, but the Australian town of Esperance charged NASA $400 for littering.
Phys.org notes that some type of space junk falls to earth every week! That includes the large Samsung satellite that crashed in a front yard in Michigan last September, and the largest space junk since 1991 hit earth just a few days ago. It was a 19.6 ton Chinese rocket that made an uncontrolled crash on May 11.
Another danger is “space weather.” National Geographic explains an event that already occurred –the “Carrington Event,” in 1859—would be a disaster if it occurred in our plugged-in world today.
The biggest solar storm on record happened in 1859, during a solar maximum about the same size as the one we’re entering, according to NASA. . . northern lights were reported as far south as Cuba and Honolulu, while southern lights were seen as far north as Santiago, Chile. . . The flares were so powerful that “people in the northeastern U.S. could read newspaper print just from the light of the aurora,”. . . In addition, the geomagnetic disturbances were strong enough that U.S. telegraph operators reported sparks leaping from their equipment—some bad enough to set fires. . .
What’s at stake. . .are the advanced technologies that underlie virtually every aspect of our lives.” . . . But the big fear is what might happen to the electrical grid, since power surges caused by solar particles could blow out giant transformers. Such transformers can take a long time to replace, especially if hundreds are destroyed at once. . . Imagine large cities without power for a week, a month, or a year.
This is not an idle threat, nor that unusual, according to PhysicsWorld.
In fact, it has now dawned on us – thanks to data from NASA’s Kepler mission, numerical modelling and the study of historical records – that the mood of our nearest star is far more hostile than we used to think. According to Jim Green, director of NASA’s planetary-science division, the Earth is, on average, in the path of Carrington-level events every 150 years – putting us five years overdue.
In recent decades, we have already seen glimpses of the dangers that could lie in store. In March 1989, for example, a geomagnetic storm that was about a third of the strength of the Carrington Event caused an electricity grid operated by the Canadian firm Hydro-Québec to fail, triggering a nine-hour blackout for about six million people. Meanwhile, the “Halloween storm” of October 2003 – which was about half as intense as Carrington – disabled a number of satellites, destroyed a dozen transformers in South Africa and crippled a large section of its power systems. These events should have been a wake-up call, but little has been done about the potential threats. As the heliophysicist Pete Worden, director of NASA’s Ames Research Center, candidly puts it: “Space weather destroys stuff.” So what can be done?
What can be done is to analyze the threat and take steps to prevent damage. That is over and over, our error. We equate “it hasn’t happened” with “it won’t happen,” so we don’t prepare. When we know there is a risk, we should be developing a plan.
And, finally, Business Insider offers its own risk factors. Here are a few:
1) The Earth’s molten core might cool. . .we’d lose our magnetosphere — and also our protection from solar winds, which would slowly blast our atmosphere into space. Mars — once rich with water and a thick atmosphere — suffered this same fate billions of years ago, leading to the nearly airless, seemingly lifeless world we know today.
2) The sun could start to die and expand. . . Right now, the sun is midway through life, steadily converting hydrogen into helium through fusion.
3) Earth could get shoved into a deadly orbit. . . According to recent simulations, in fact, rogue planets may outnumber stars in the Milky Way by 100,000 to one. . . A world that’s large enough and drifts close enough could even kick us out of the solar system entirely. (Or cause us to collide with a nearby planet, like Venus or Mercury.)
4) A rogue planet could hit Earth. . . It wouldn’t be unprecedented. . .a small planet crashed into a larger planet in the solar system — forming Earth and its moon.
OK. Not much we can do about the last list. But we can plan to divert or destroy asteroids, clean up our mess of space trash, modernize and strengthen our electric grid, have contingency plans in case there is an outage—and look for other risks and what we might do about them. Repeatedly, we wait until people are already dying before we take serious action.