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NASA videos show what sunsets look like elsewhere in the galaxy
On other planets, blue skies and red sunsets aren't the norm.

- A NASA scientist created animated simulations of how sunsets likely appear on Mars, Venus, Uranus, and Titan, Saturn's largest moon.
- Sunsets appear differently on other planets because of differences in the atmosphere, which scatters light in unique ways.
- Studying alien atmospheres helps scientists better understand atmospheric processes on Earth, and helps narrow the search for habitable planets.
New video simulations from NASA offer a glimpse of what sunsets might look like on other planets.
Created by Geronimo Villanueva, a planetary scientist at NASA's Goddard Space Flight Center, the simulations are part of a computer modeling tool that scientists could someday use to study extraterrestrial atmospheres on probe missions. Villanueva simulated how skies might look as day turns to night on Venus, Mars, Uranus, and Saturn's largest moon, Titan.
"The animations show all-sky views as if you were looking up at the sky through a super wide camera lens from Earth, Venus, Mars, Uranus, and Titan," NASA wrote in a blog post. "The white dot represents the location of the Sun."
The simulations reveal sunsets that look quite different from those on Earth. On Uranus, for example, the sky morphs from a royal blue to a hazy brownish-yellow. Why the difference? The color of the sky on any planet is determined by the unique blend of molecules in the atmosphere. When incoming sunlight passes through the atmosphere, these molecules scatter light in specific ways, causing light of certain wavelengths to appear more visible to the human eye.
"When sunlight — which is made up of all the colors of the rainbow — reaches Uranus's atmosphere, hydrogen, helium and methane absorb the longer-wavelength red portion of the light," NASA wrote. "The shorter-wavelength blue and green portions of light get scattered as photons bounce off the gas molecules and other particles in the atmosphere. A similar phenomenon makes Earth's sky appear blue on a clear day."
So, why do skies change color as day turns to night? During the day, sunlight travels through the atmosphere to our eyes on a relatively short path. But as the sun sets, light must take a longer path through the atmosphere, which provides more opportunities for shorter wavelengths (blue) to be scattered.
An illustration of Rayleigh scattering.
Scientificprotocols via YouTube
The result is a red sunset, produced by an optical phenomenon called Rayleigh scattering.
A sunset on Mars. Taken by the Viking 2 Lander on June 14, 1978, this was the first photo of an alien sunset.
NASA
Villanueva's simulations are now featured on NASA's Planetary Spectrum Generator, an online tool for studying the atmospheres and surfaces of distant planets. Studying alien atmospheres not only helps scientists better understand atmospheric processes on Earth, but also gives them a clearer idea of which planets may be habitable — or harbor life already.
- Mars is closer and brighter than it has been in 15 years - Big Think ›
- Is NASA ignoring proof of Martian life from the 1970s? ›
- What is the summer solstice? An astronomer explains ›
- Venus' clouds shows signs of alien life, MIT scientists say - Big Think ›
How tiny bioelectronic implants may someday replace pharmaceutical drugs
Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.
Left: The vagus nerve, the body's longest cranial nerve. Right: Vagus nerve stimulation implant by SetPoint Medical.
- Bioelectronic medicine is an emerging field that focuses on manipulating the nervous system to treat diseases.
- Clinical studies show that using electronic devices to stimulate the vagus nerve is effective at treating inflammatory diseases like rheumatoid arthritis.
- Although it's not yet approved by the US Food and Drug Administration, vagus nerve stimulation may also prove effective at treating other diseases like cancer, diabetes and depression.
The nervous system’s ancient reflexes
<p>You accidentally place your hand on a hot stove. Almost instantaneously, your hand withdraws.</p><p>What triggered your hand to move? The answer is <em>not</em> that you consciously decided the stove was hot and you should move your hand. Rather, it was a reflex: Skin receptors on your hand sent nerve impulses to the spinal cord, which ultimately sent back motor neurons that caused your hand to move away. This all occurred before your "conscious brain" realized what happened.</p><p>Similarly, the nervous system has reflexes that protect individual cells in the body.</p><p>"The nervous system evolved because we need to respond to stimuli in the environment," said Dr. Tracey. "Neural signals don't come from the brain down first. Instead, when something happens in the environment, our peripheral nervous system senses it and sends a signal to the central nervous system, which comprises the brain and spinal cord. And then the nervous system responds to correct the problem."</p><p>So, what if scientists could "hack" into the nervous system, manipulating the electrical activity in the nervous system to control molecular processes and produce desirable outcomes? That's the chief goal of bioelectronic medicine.</p><p>"There are billions of neurons in the body that interact with almost every cell in the body, and at each of those nerve endings, molecular signals control molecular mechanisms that can be defined and mapped, and potentially put under control," Dr. Tracey said in a <a href="https://www.youtube.com/watch?v=AJH9KsMKi5M" target="_blank">TED Talk</a>.</p><p>"Many of these mechanisms are also involved in important diseases, like cancer, Alzheimer's, diabetes, hypertension and shock. It's very plausible that finding neural signals to control those mechanisms will hold promises for devices replacing some of today's medication for those diseases."</p><p>How can scientists hack the nervous system? For years, researchers in the field of bioelectronic medicine have zeroed in on the longest cranial nerve in the body: the vagus nerve.</p>The vagus nerve
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYyOTM5OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NTIwNzk0NX0.UCy-3UNpomb3DQZMhyOw_SQG4ThwACXW_rMnc9mLAe8/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="09add" class="rm-shortcode" data-rm-shortcode-id="f38dbfbbfe470ad85a3b023dd5083557" data-rm-shortcode-name="rebelmouse-image" data-width="1245" data-height="700" />Electrical signals, seen here in a synapse, travel along the vagus nerve to trigger an inflammatory response.
Credit: Adobe Stock via solvod
<p>The vagus nerve ("vagus" meaning "wandering" in Latin) comprises two nerve branches that stretch from the brainstem down to the chest and abdomen, where nerve fibers connect to organs. Electrical signals constantly travel up and down the vagus nerve, facilitating communication between the brain and other parts of the body.</p><p>One aspect of this back-and-forth communication is inflammation. When the immune system detects injury or attack, it automatically triggers an inflammatory response, which helps heal injuries and fend off invaders. But when not deployed properly, inflammation can become excessive, exacerbating the original problem and potentially contributing to diseases.</p><p>In 2002, Dr. Tracey and his colleagues discovered that the nervous system plays a key role in monitoring and modifying inflammation. This occurs through a process called the <a href="https://www.nature.com/articles/nature01321" target="_blank" rel="noopener noreferrer">inflammatory reflex</a>. In simple terms, it works like this: When the nervous system detects inflammatory stimuli, it reflexively (and subconsciously) deploys electrical signals through the vagus nerve that trigger anti-inflammatory molecular processes.</p><p>In rodent experiments, Dr. Tracey and his colleagues observed that electrical signals traveling through the vagus nerve control TNF, a protein that, in excess, causes inflammation. These electrical signals travel through the vagus nerve to the spleen. There, electrical signals are converted to chemical signals, triggering a molecular process that ultimately makes TNF, which exacerbates conditions like rheumatoid arthritis.</p><p>The incredible chain reaction of the inflammatory reflex was observed by Dr. Tracey and his colleagues in greater detail through rodent experiments. When inflammatory stimuli are detected, the nervous system sends electrical signals that travel through the vagus nerve to the spleen. There, the electrical signals are converted to chemical signals, which trigger the spleen to create a white blood cell called a T cell, which then creates a neurotransmitter called acetylcholine. The acetylcholine interacts with macrophages, which are a specific type of white blood cell that creates TNF, a protein that, in excess, causes inflammation. At that point, the acetylcholine triggers the macrophages to stop overproducing TNF – or inflammation.</p><p>Experiments showed that when a specific part of the body is inflamed, specific fibers within the vagus nerve start firing. Dr. Tracey and his colleagues were able to map these relationships. More importantly, they were able to stimulate specific parts of the vagus nerve to "shut off" inflammation.</p><p>What's more, clinical trials show that vagus nerve stimulation not only "shuts off" inflammation, but also triggers the production of cells that promote healing.</p><p>"In animal experiments, we understand how this works," Dr. Tracey said. "And now we have clinical trials showing that the human response is what's predicted by the lab experiments. Many scientific thresholds have been crossed in the clinic and the lab. We're literally at the point of regulatory steps and stages, and then marketing and distribution before this idea takes off."<br></p>The future of bioelectronic medicine
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYxMDYxMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjQwOTExNH0.uBY1TnEs_kv9Dal7zmA_i9L7T0wnIuf9gGtdRXcNNxo/img.jpg?width=980" id="8b5b2" class="rm-shortcode" data-rm-shortcode-id="c005e615e5f23c2817483862354d2cc4" data-rm-shortcode-name="rebelmouse-image" data-width="2000" data-height="1125" />Vagus nerve stimulation can already treat Crohn's disease and other inflammatory diseases. In the future, it may also be used to treat cancer, diabetes, and depression.
Credit: Adobe Stock via Maridav
<p>Vagus nerve stimulation is currently awaiting approval by the US Food and Drug Administration, but so far, it's proven safe and effective in clinical trials on humans. Dr. Tracey said vagus nerve stimulation could become a common treatment for a wide range of diseases, including cancer, Alzheimer's, diabetes, hypertension, shock, depression and diabetes.</p><p>"To the extent that inflammation is the problem in the disease, then stopping inflammation or suppressing the inflammation with vagus nerve stimulation or bioelectronic approaches will be beneficial and therapeutic," he said.</p><p>Receiving vagus nerve stimulation would require having an electronic device, about the size of lima bean, surgically implanted in your neck during a 30-minute procedure. A couple of weeks later, you'd visit, say, your rheumatologist, who would activate the device and determine the right dosage. The stimulation would take a few minutes each day, and it'd likely be unnoticeable.</p><p>But the most revolutionary aspect of bioelectronic medicine, according to Dr. Tracey, is that approaches like vagus nerve stimulation wouldn't come with harmful and potentially deadly side effects, as many pharmaceutical drugs currently do.</p><p>"A device on a nerve is not going to have systemic side effects on the body like taking a steroid does," Dr. Tracey said. "It's a powerful concept that, frankly, scientists are quite accepting of—it's actually quite amazing. But the idea of adopting this into practice is going to take another 10 or 20 years, because it's hard for physicians, who've spent their lives writing prescriptions for pills or injections, that a computer chip can replace the drug."</p><p>But patients could also play a role in advancing bioelectronic medicine.</p><p>"There's a huge demand in this patient cohort for something better than they're taking now," Dr. Tracey said. "Patients don't want to take a drug with a black-box warning, costs $100,000 a year and works half the time."</p><p>Michael Dowling, president and CEO of Northwell Health, elaborated:</p><p>"Why would patients pursue a drug regimen when they could opt for a few electronic pulses? Is it possible that treatments like this, pulses through electronic devices, could replace some drugs in the coming years as preferred treatments? Tracey believes it is, and that is perhaps why the pharmaceutical industry closely follows his work."</p><p>Over the long term, bioelectronic approaches are unlikely to completely replace pharmaceutical drugs, but they could replace many, or at least be used as supplemental treatments.</p><p>Dr. Tracey is optimistic about the future of the field.</p><p>"It's going to spawn a huge new industry that will rival the pharmaceutical industry in the next 50 years," he said. "This is no longer just a startup industry. [...] It's going to be very interesting to see the explosive growth that's going to occur."</p>U.S. Navy controls inventions that claim to change "fabric of reality"
Inventions with revolutionary potential made by a mysterious aerospace engineer for the U.S. Navy come to light.
U.S. Navy ships
- U.S. Navy holds patents for enigmatic inventions by aerospace engineer Dr. Salvatore Pais.
- Pais came up with technology that can "engineer" reality, devising an ultrafast craft, a fusion reactor, and more.
- While mostly theoretical at this point, the inventions could transform energy, space, and military sectors.
High frequency gravitational wave generator.
Credit: Dr. Salvatore Pais
A craft using an inertial mass reduction device.
Credit: Salvatore Pais
Laser Augmented Turbojet Propulsion System
Credit: Dr. Salvatore Pais
Physicist creates AI algorithm that may prove reality is a simulation
A physicist creates an AI algorithm that predicts natural events and may prove the simulation hypothesis.
Pixellated head simulation.
- Princeton physicist Hong Qin creates an AI algorithm that can predict planetary orbits.
- The scientist partially based his work on the hypothesis which believes reality is a simulation.
- The algorithm is being adapted to predict behavior of plasma and can be used on other natural phenomena.
Physicist Hong Qin with images of planetary orbits and computer code.
Credit: Elle Starkman
Are we living in a simulation? | Bill Nye, Joscha Bach, Donald Hoffman | Big Think
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How different people react to threats of violence.
Eight women at the forefront of the world’s COVID-19 response
Beyond making up 70% of the world's health workers, women researchers have been at the cutting edge of coronavirus research.
