Did you know that our planet is surrounded by giant, donut-shaped clouds of radiation?
Here’s what you need to know.
The Van Allen radiation belts exist because fast-moving charged particles get trapped inside Earth’s natural magnetic field, forming two concentric donut-shaped clouds of radiation. Other planets with global magnetic fields, like Jupiter, also have radiation belts.
Earth’s radiation belts were first identified in 1958 by Explorer 1, the first U.S. satellite. The inner belt, composed predominantly of protons, and the outer belt, mostly electrons, would come to be named the Van Allen Belts, after James Van Allen, the scientist who led the charge designing the instruments and studying the radiation data from Explorer 1.
In 2012, we launched the twin Van Allen Probes to study the radiation belts. Over the past six years, these spacecraft have orbited in and out of the belts, providing brand-new data about how the radiation belts shift and change in response to solar activity and other factors.
Shortly after launch, the Van Allen Probes detected a previously-unknown third radiation belt, created by a bout of strong solar activity. All the extra energy directed towards Earth meant that some particles trapped in our planet’s magnetic field were swept out into the usually relatively empty region between the two Van Allen Belts, creating an additional radiation belt.
Originally designed for a two-year mission, the Van Allen Probes have spent more than six years collecting data in the harsh radiation environment of the Van Allen Belts. In spring 2019, we’re changing their orbit to bring the perigee — the part of the orbit where the spacecraft are closest to Earth — about 190 miles lower. This ensures that the spacecraft will eventually burn up in Earth’s atmosphere, instead of orbiting forever and becoming space junk.
Because the Van Allen Probes have proven to be so hardy, they’ll continue collecting data throughout the final months of the mission until they run out of fuel. As they skim through the outer reaches of Earth’s atmosphere, scientists and engineers will also learn more about how atmospheric oxygen can degrade satellite measurements — information that can help build better satellites in the future.
Keep up with the latest on the mission on Twitter, Facebook or nasa.gov/vanallenprobes.
Good afternoon, the academic culture of “if you’re not overworking, you don’t deserve success” is unhealthy.
have I mentioned that one week ago TODAY i launched a sounding ROCKET? (model pictured above)
Let’s just talk about how much I love space... and my Nikon. 1/12/2018
Grades don’t determine your intelligence.
Grades don’t determine your intelligence.
Grades don’t determine your intelligence.
Grades don’t determine your intelligence.
So long, Oppy.
This article will require that you get a bowl of cheerios and a glass of wine, sit in a chair with the blanket around you and your dog or cat next to you, and just zone out. It’s frightening, but it’s not sci-fi (or cli-fi). It’s based on what the scientists are telling us, if we read the actual IPCC report and not just the “what we worry?” summary.
Excerpt:
The new report’s worst-case scenario is, actually, a best case. In fact, it is a beyond-best-case scenario. What has been called a genocidal level of warming is already our inevitable future. The question is how much worse than that it will get.
By and large the consensus is the same: We are on track for four degrees of warming, more than twice as much as most scientists believe is possible to endure without inflicting climate suffering on hundreds of millions or threatening at least parts of the social and political infrastructure we call, grandly, “civilization.” The only thing that changed, this week, is that the scientists, finally, have hit the panic button.
Because the numbers are so small, we tend to trivialize the differences between one degree and two, two degrees and four. Human experience and memory offers no good analogy for how we should think about those thresholds, but with degrees of warming, as with world wars or recurrences of cancer, you don’t want to see even one.
At two degrees, the melting of ice sheets will pass a tipping point of collapse, flooding dozens of the world’s major cities this century. At that amount of warming, it is estimated, global GDP, per capita, will be cut by 13 percent. Four hundred million more people will suffer from water scarcity, and even in the northern latitudes heat waves will kill thousands each summer. It will be worse in the planet’s equatorial band. In India, where many cities now numbering in the many millions would become unliveably hot, there would be 32 times as many extreme heat waves, each lasting five times as long and exposing, in total, 93 times more people. This is two degrees — practically speaking, our absolute best-case climate scenario.
And the World War II mobilization metaphor is not hyperbole. To avoid warming of the kind the IPCC now calls catastrophic requires a complete rebuilding of the entire energy infrastructure of the world, a thorough reworking of agricultural practices and diet to entirely eliminate carbon emissions from farming, and a battery of cultural changes to the way those of us in the wealthy West, at least, conduct our lives. And we need to do all of that in two, or possibly three, decades. As a comparison, simply the last phase of the recent three-stop extension of New York City’s Second Avenue subway line took 12 years. All told, from the first groundbreaking, the project took 45 years.
In whatever you choose to do, do it because it’s hard, not because it’s easy. Math and physics and astrophysics are hard. For every hard thing you accomplish, fewer other people are out there doing the same thing as you. That’s what doing something hard means. And in the limit of this, everyone beats a path to your door because you’re the only one around who understands the impossible concept or who solves the unsolvable problem.
Neil deGrasse Tyson (via mathblab)
emi | astrophysics | maths | intj | flutist | = | coffee guru
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