How to Catch a Gravity Wave - Conclusion
Looking Out, Looking In, Thinking, and Working Together
(Credits: left image-NASA/Swift/Dana Berry; Right image-The Virgo Collaboration/CCO 1.0)
"The questioning explorers also started looking inward, inside their own bodies...smallpox, perhaps the most deadly and terrifying disease in human history, was eliminated from the planet."
"When we use unbiased, scientific reasoning, work together across national borders, setting aside petty differences, it's astonishing what we two-legged upright humans can accomplish."
Thinking Small for Big Gains
The questioning explorers also started looking inward, inside their own bodies (which could also be dangerous back then), and even into the micro-world of exceedingly small microbes and even smaller viruses. With the knowledge acquired by simple scientific thinking and clever experiments they figured out how to make a vacine that would train the body's immune system to defeat some very dangerous viruses.
Smallpox, perhaps the deadliest and most terrifying disease in human history, was eliminated from the planet. Then came polio, the most feared disease of the first half of the 20th century. It is very close to being eliminated on this planet. Less frightening, but still dangerous, viral infections like chickenpox, mumps, and measles have also been nearly eradicated. Elimination is being slowed by misinformed and gullible humans who still seem to prefer stories, mistruths, and superstition, over life saving vaccines. Go figure.
(Credit: CDC/Public Health Image Library {PHIL})
But the wave was getting very close, and still no one suspected the existence of gravity waves.
Mass and Energy - Two Sides of the Same Coin
Then, just a little more than a century before the wave arrived, a young scientist working in a patent office published some thoughts and equations that shook the world. In a couple of little scientific papers, published about 10 years apart, he predicted, among other things, that the speed of light is a universal constant, and that matter can be converted to energy according to the well-known formula E=mc^2.
This formula says that mass and energy are connected and, under the right circumstances, one can be converted into the other. Fortunately, it's difficult under "normal" earth conditions, to make this happen. Because even a small amount of mass, if converted quickly, will become a huge amount of energy.
The young physicist, named Albert Einstein, also predicted, the existence of gravity waves. He predicted them but thought they would probably be far too faint for human-made instruments to detect or measure.
Nevertheless, scientists kept plugging and science continued to advance. Countless experiments, conducted on more and more sophisticated instruments, verified again and again the accuracy of Einstein's predictions concerning the nature of energy, mass, light, and the effect of gravity on space-time.
Scientists and engineers also exploded some really big bombs that demonstrated noticeably the truth of Einstein's formulas. Any lay person, no matter how resistant to new knowledge, could understand that bit of data.
Still, as Einstein had speculated, the gravity waves remained elusive.
Can It Really Be Done?
Gravity waves really do distort what is often called the space-time continuum, or just space-time. The lengths of physical objects change when a gravity wave passes through them. All you have to do to detect such a wave is somehow notice and measure a change in space-time.
Yes, that does sound hard. It's further complicated by the vastness of the universe. Gravity waves arriving at Earth after traveling millions or billions of light years are very small and faint.
How faint? Well, let's say you could build two 4-kilometer-long tubes, each containing an almost perfect vacuum. And say you could connect the two tubes at one end at a 90-degree angle — an L-shape, if you will. Then you could fire a laser beam into a beam splitter at the end where the two tubes come together. If done just right, that would divide the beam into two beams, one traveling down each tube. At the other end of each tube you would hang an exquisitely precisely placed mirror to reflect the beams back to the source.
Along comes a gravity wave that passes through the beams. True to the nature of a gravity wave, each beam is actually stretched a little bit. How little of a bit? The beam's length would increase by 1/10,000th of the diameter of a proton! And the length change of each of the two beams would occur within 10 milliseconds of each other. If you could detect that, you would know that you had probably found a gravity wave.
Is that even possible? Now you know why Einstein suspected that scientists might find that hard to do.
But that was over a hundred years ago. Alot has happened since then that even Einstein couldn't have imagined. Those tenacious scientists kept learning and imagining. Just a few decades before the arrival of the gravity wave described at the beginning of this article, they conceived of that 4-kilometer tube with the split laser beam and perfect mirrors, in an almost perfect vacuum. Just a few years before it's arrival, they had completed several of them.
They are engineering and scientific marvels, and they worked. Before our gravity waves arrived, they had detected other gravity wave events. But not from neutron stars. The first detected waves were from black hole collisions, even further away.
Important Interlude:
As you may have guessed by now, this isn't really a story about neutron stars or gravity waves. It is story about human growth and the power of the scientific method. When we use unbiased, scientific reasoning, work together across national borders, and set aside petty differences, it's astonishing what we two-legged upright, two-handed, humans can accomplish.
At the end of this page, I provide some links to learn more about LIGO, neutron stars, gravity waves, and in particular the neutron star collision that inspired this true story. You shall visit them!
And now to conclude this epic adventure:
When the gravity waves from the neutron star collision of 130 million years ago reached the small blue planet, the gravity wave detectors, against all probability, were waiting.
Three specific instruments and the scientists that operate them, working together, are the heroes of this amazing true story. Two of the instruments are in the United States. They are both designated as a “Laser Interferometer Gravitational Wave Observatory”, or LIGO for short. One LIGO is in Hanford, Washington. The other is in Livingston, Louisiana. The third instrument, named Virgo, is near Pisa, Italy.
(Credit: CalTech-MIT-LIGO Lab)
Now follow in real time:
August 17, 2017, 8:41 am, Eastern Daylight Time: The two United States LIGO instruments detect a gravity wave signal that ripples through their detectors for around 100 seconds. The Fermi space telescope detects a gamma ray burst 1.7 seconds later. Virgo in Italy also detects the gamma rays. The LIGO events are fractions of seconds apart. Using the tiny differences in detection times the scientists are able to pinpoint a section of sky from where the signal came. Ninety observatories all over the world are alerted. Their telescopes are turned toward the predicted region, and they see…a new light in the sky!
(Credit: NASA-ESA)
Against All Odds, We Did It
No observant being watching the upright walkers for most of their existence, would have bet a pebble that they would ever have imagined the existence of, and then built an instrument to detect, that wave.
Much was discovered from the data collected and still being analyzed by the observatories all over the world and in space. Unexpected things were learned. Some theories were proven, and others disproven.
We learned that neutron collisons are one of the ways that gold, platinum, and other heavy metals are created. That had been theorized, but not proven until this event. I'm pondering my gold wedding band. It came from a neutron star collision, or similar cataclysmic event, far away and long ago.
We now know that at least one source of those, once mysterious, short gamma ray bursts is colliding neutron stars. Again, previously theorized, but not known for sure.
The list of new knowledge is long and getting longer. The provided links will help curious learners find out more.
When we team together, calmly, thoughfully, asking questions, and finding ways to test and answer those questions, without bogging our brains with made-up untested stories, it's astonishing what we can achieve.
Learn more about gravity waves, neutron stars, LIGO and what we're learning there from the following links:SEE THIS VIDEO FIRST! It's cool.
LIGO Gravitational-Wave Observatory - Description of discovery
FT Exploring: Home Page
I never interrupt my content with those annoying ads
Help me keep it that way by using the share button below:
