If it is black, then it could be as large as meters; if it is not so dark, it should be about meters in size. And by the way, how close will FT3 get to the Earth? Some planets, such as Mercury, Venus or Mars, get closer to the Earth sometimes! This small asteroid will be so far —again— that it will be very difficult to obtain a decent image of it.
We will have to wait until , and even then it will pass Awarded a honoris causa degree for his contributions to the dissemination of science, the author has been a member of the Alpha Planetarium Astronomical Society since He is now also an honorary member. ORG, www. Notify me of follow-up comments by email. Notify me of new posts by email.
Sign in. Log into your account. Password recovery. Recover your password. Forgot your password? Get help. Es En. Asteroid fliegt auf Erde zu. So what would happen if scientists detected an asteroid approaching Earth? Life is good. Greetings and clear skies About the author Awarded a honoris causa degree for his contributions to the dissemination of science, the author has been a member of the Alpha Planetarium Astronomical Society since Human-Computer Fusion.
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Eugenio Garza Sada No. A rolling death smog that suffocates millions. Our lungs need oxygen, but that is only a fraction of what we breathe. The fraction of carbon dioxide is growing: It just crossed parts per million, and high-end estimates extrapolating from current trends suggest it will hit 1, ppm by At that concentration, compared to the air we breathe now, human cognitive ability declines by 21 percent.
Other stuff in the hotter air is even scarier, with small increases in pollution capable of shortening life spans by ten years. The warmer the planet gets, the more ozone forms, and by mid-century, Americans will likely suffer a 70 percent increase in unhealthy ozone smog, the National Center for Atmospheric Research has projected.
Which does make you think again about the autism epidemic in West Hollywood. Already, more than 10, people die each day from the small particles emitted from fossil-fuel burning; each year, , people die from wildfire smoke, in part because climate change has extended forest-fire season in the U.
By , according to the U. Forest Service , wildfires will be twice as destructive as they are today; in some places, the area burned could grow fivefold. What worries people even more is the effect that would have on emissions, especially when the fires ravage forests arising out of peat. Peatland fires in Indonesia in , for instance, added to the global CO2 release by up to 40 percent, and more burning only means more warming only means more burning. That is especially bad because the Amazon alone provides 20 percent of our oxygen.
Then there are the more familiar forms of pollution. Literally unbreathable. That year, smog was responsible for a third of all deaths in the country. The violence baked into heat. Climatologists are very careful when talking about Syria.
They want you to know that while climate change did produce a drought that contributed to civil war, it is not exactly fair to saythat the conflict is the result of warming; next door, for instance, Lebanon suffered the same crop failures. But researchers like Marshall Burke and Solomon Hsiang have managed to quantify some of the non-obvious relationships between temperature and violence: For every half-degree of warming, they say, societies will see between a 10 and 20 percent increase in the likelihood of armed conflict.
In climate science, nothing is simple, but the arithmetic is harrowing: A planet five degrees warmer would have at least half again as many wars as we do today. Overall, social conflict could more than double this century. This is one reason that, as nearly every climate scientist I spoke to pointed out, the U. What accounts for the relationship between climate and conflict?
Some of it comes down to agriculture and economics; a lot has to do with forced migration, already at a record high, with at least 65 million displaced people wandering the planet right now.
But there is also the simple fact of individual irritability. Heat increases municipal crime rates, and swearing on social media, and the likelihood that a major-league pitcher, coming to the mound after his teammate has been hit by a pitch, will hit an opposing batter in retaliation.
And the arrival of air-conditioning in the developed world, in the middle of the past century, did little to solve the problem of the summer crime wave. Dismal capitalism in a half-poorer world. The murmuring mantra of global neoliberalism, which prevailed between the end of the Cold War and the onset of the Great Recession, is that economic growth would save us from anything and everything.
Before fossil fuels, nobody lived better than their parents or grandparents or ancestors from years before, except in the immediate aftermath of a great plague like the Black Death, which allowed the lucky survivors to gobble up the resources liberated by mass graves. Of course, that onetime injection has a devastating long-term cost: climate change. The most exciting research on the economics of warming has also come from Hsiang and his colleagues, who are not historians of fossil capitalism but who offer some very bleak analysis of their own: Every degree Celsius of warming costs, on average, 1.
This is the sterling work in the field, and their median projection is for a 23 percent loss in per capita earning globally by the end of this century resulting from changes in agriculture, crime, storms, energy, mortality, and labor.
Tracing the shape of the probability curve is even scarier: There is a 12 percent chance that climate change will reduce global output by more than 50 percent by , they say, and a 51 percent chance that it lowers per capita GDP by 20 percent or more by then, unless emissions decline. By comparison, the Great Recession lowered global GDP by about 6 percent, in a onetime shock; Hsiang and his colleagues estimate a one-in-eight chance of an ongoing and irreversible effect by the end of the century that is eight times worse.
The scale of that economic devastation is hard to comprehend, but you can start by imagining what the world would look like today with an economy half as big, which would produce only half as much value, generating only half as much to offer the workers of the world. It makes the grounding of flights out of heat-stricken Phoenix last month seem like pathetically small economic potatoes.
And, among other things, it makes the idea of postponing government action on reducing emissions and relying solely on growth and technology to solve the problem an absurd business calculation.
Every round-trip ticket on flights from New York to London, keep in mind, costs the Arctic three more square meters of ice. Sulfide burps off the skeleton coast. That the sea will become a killer is a given.
Barring a radical reduction of emissions, we will see at least four feet of sea-level rise and possibly ten by the end of the century. At least million people live within ten meters of sea level today. But the drowning of those homelands is just the start. There, the small fish die out, unable to breathe, which means oxygen-eating bacteria thrive, and the feedback loop doubles back.
Hydrogen sulfide is so toxic that evolution has trained us to recognize the tiniest, safest traces of it, which is why our noses are so exquisitely skilled at registering flatulence. Plants, too. It was millions of years before the oceans recovered. Our present eeriness cannot last. Surely this blindness will not last — the world we are about to inhabit will not permit it. Humans used to watch the weather to prophesy the future; going forward, we will see in its wrath the vengeance of the past.
You can find it already watching footage of an iceberg collapsing into the sea — a feeling of history happening all at once. It is. Many people perceive climate change as a sort of moral and economic debt, accumulated since the beginning of the Industrial Revolution and now come due after several centuries — a helpful perspective, in a way, since it is the carbon-burning processes that began in 18th-century England that lit the fuse of everything that followed.
But more than half of the carbon humanity has exhaled into the atmosphere in its entire history has been emitted in just the past three decades; since the end of World War II, the figure is 85 percent. She has been smoking for 57 of those years, unfiltered. Some of the men who first identified a changing climate and given the generation, those who became famous were men are still alive; a few are even still working.
Like most of those who first raised the alarm, he believes that no amount of emissions reduction alone can meaningfully help avoid disaster.
Jim Hansen is another member of this godfather generation. Hansen has recently given up on solving the climate problem with a carbon tax alone, which had been his preferred approach, and has set about calculating the total cost of the additional measure of extracting carbon from the atmosphere.
Hansen began his career studying Venus, which was once a very Earth-like planet with plenty of life-supporting water before runaway climate change rapidly transformed it into an arid and uninhabitable sphere enveloped in an unbreathable gas; he switched to studying our planet by 30, wondering why he should be squinting across the solar system to explore rapid environmental change when he could see it all around him on the planet he was standing on.
The answer, they suggested, is that the natural life span of a civilization may be only several thousand years, and the life span of an industrial civilization perhaps only several hundred. Then their combined gravitational attraction keeps the next layer glued.
Then their total weight grips the next layer. I think you get the idea, but this process repeats until the entire might of the Earth — all 5. So if you want to blow up the Earth, you need to unpeel that onion, one layer at a time. You need to send every layer, every chunk of rock and speck of dirt and shovelful of molten magma into space.
And not just into space temporarily — you need to make sure that stuff completely escapes the gravitational pull of the remaining Earth for all eternity. In other words, you need to accelerate all the parts of the Earth to escape velocity. That's no easy feat: We typically use giant rockets to hurl a few measly tons into orbit and beyond.
Although once you get started, the going gets easier. With every kilogram sent into the void, that's one less kilogram that's holding back the next kilogram. As you unpeel the Earth, layer by layer, the gravitational pull gets weaker and each layer is easier than the last to launch. By the time you're nearly done and you're packing our iron core into interstellar moving boxes, it'd be no different than doing the same to a small moon.
This entire process can be summarized by a handy equation that relates the energy needed to destroy a planet or in more polite terms, "unbind" it to its mass and radius. The equation assumes a uniform density of the planet under consideration, allowing for a rough estimate.
That's a lot of energy. So if you were to somehow capture all the energy output of our nuclear power plants, hydroelectric dams, coal plants, solar panels and wind farms — leaving absolutely nothing else for anybody else — you would need to wait a trillion years to reach the amount we're talking here.
A trillion years to collect enough energy to completely rip apart the Earth. If you want to be taken seriously as a threatening mad scientist, you need a new plan.
After all, our sun will burn out in only 5 billion years, and there wouldn't be much point in destroying the Earth after that, would there?
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