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Here’s the view from humanity’s furthest spacecraft
Already 14 billion miles from the Sun, Voyager 1 is speeding away at 38,000 mph.
- Jimmy Carter was U.S. president and Elvis Presley was still alive in 1977, the year Voyager 1 was launched.
- Back in 1990, Voyager 1's last picture showed Earth as nothing more than a 'Pale Blue Dot'.
- Voyager 1 is now traversing interstellar space – here's what our solar system looks like from there.
Speeding towards the Serpent-bearer
Voyager 1 lifting off from Cape Canaveral on September 5, 1977.
Credit: NASA, public domain
What's the farthest place that humanity has gone? For a practical answer to that question rather than a philosophical one, direct your gaze to Ophiuchus, an equatorial constellation also known as Serpentarius.
Speeding towards Rasalhague and the other stars that make up the 'Serpent-bearer' is Voyager 1, the furthest human-made object in the Universe. It's currently 14.1 billion miles (22.8 billion km) from the Sun and speeding away at roughly 38,000 mph (61,000 km/h).
That's too far to observe Voyager 1 twinkle in the night sky. But you can turn the tables and see what it sees, as it looks back at us. Via NASA's Eyes website (and app), you can pay a virtual visit to where the spacecraft is now and explore its vantage as it hurtles towards the edge of the solar system.
There's Jupiter and Saturn, so seemingly close together; and Uranus, Pluto and Neptune, their orbits farther away. At the center of it all, the Sun. Nearby, the inner planets, including Earth: so close to it that they don't even get a name-tag. Those planets and their trajectories are so familiar yet now so distant, it's enough to make you homesick by proxy!
You can click and drag your way around Voyager 1, shifting your perspective to explore the region – spotting Sedna, Halley's Comet and a few other less familiar members of our solar family.
67 MB of data
Where it's at: this is what the view of the solar system is from Voyager 1 as it speeds into interstellar space.
Credit: NASA's Eyes, public domain
Although it's still sending data back to Earth, most of Voyager 1's instruments have now been powered down, and the craft is expected to go entirely dead by 2030 at the latest; but its incredible journey isn't over. In fact, it will most likely continue long after you, I and everything we know will have disappeared. Here's how it all started.
The year is 1977. Jimmy Carter's first year as president. Elvis Presley's last year alive. Star Wars hits the big screen. On September 10, Hamida Djandoubi becomes the last person ever to be guillotined in France. Five days earlier, Voyager 1 takes off from Cape Canaveral.
Voyager 1 is a small craft, weighing barely 1,820 lb. (825.5 kg). Its most prominent feature is a 12-ft (3.7-m) wide dish antenna, for talking with Earth – when there's no straight line of communication, a Digital Tape Recorder kicks in, able to hold up to 67 MB of data for later transmission. In all, Voyager 1 carries 11 different instruments to study the heavens.
Voyager 1 and its range of instruments, which have been progressively shut down as the craft's power waned.
Credit: NASA/Hulton Archive/Getty Images
The idea for the Voyagers, 1 and 2, grew out of the Mariner program's focus on the outer planets. The Voyagers got their own name as their field of study started to diverge towards the outer heliosphere and beyond.
The heliosphere is the 'solar bubble' created by the solar wind, i.e. the plasma emitted by the Sun. The region where solar wind slows down to below the speed of sound is called the termination shock. The heliopause is the outer limit of this bubble, where outward movement of solar plasma is nullified by interstellar plasma from the rest of the Milky Way. Beyond lies interstellar space.
The Voyagers were built to withstand the intense radiation in those far reaches of space – in part by applying a protective layer of kitchen-grade aluminum foil.
Humanity's farthest probe into the Universe was launched on September 5, 1977, confusingly 16 days after Voyager 2. More than 43 years later, the craft is still sending data back to Earth – but not for very much longer. Here are a few snapshots for the family album:
- December 19, 1977: Voyager 1 overtakes Voyager 2. Voyager 1 is travelling at a speed of 3.6 AU per year, while Voyager 2 is only going at 3.3 AU. So, Voyager 1 is constantly increasing its lead over its slower brother.
- Early 1979: Voyager 1 flies by Jupiter and its moons, taking close-ups of Jupiter's Great Red Spot and spotting volcanic activity on the moon Io – the first time ever this was observed outside Earth.
- Late 1980: flyby of Saturn and its moons, especially Titan. The flybys of the two gas giants gave 'gravity assists' that helped Voyager 1 continue its journey.
- February 14, 1990: Voyager takes a 'Solar System Family Portrait', its final picture and the first one of the solar system from the outside. It included an image of the Earth from 6 billion km (3.7 billion mi) away, as a 'Pale Blue Dot'.
- February 17, 1998: Voyager 1 reaches 69.4 AU from the Sun, overtaking Pioneer 10 and becoming the most distant spacecraft sent from Earth.
- 2004: Voyager 1 becomes the first craft to reach termination shock, at about 94 AU from the Sun. The Astronomic Unit (AU) is the average distance from Sun to Earth (about 93 million mi, 150 million km or 8 light minutes).
- August 25, 2012: after a few months of 'cosmic purgatory' and 10 days before the 35th anniversary of its launch, Voyager 1 became the first human-made vessel to cross the heliopause, at 121 AU, thus entering interstellar space.
- Soon after, Voyager 1 entered a region still under some influence of the Sun, which scientists dubbed the 'magnetic highway'.
- November 28, 2017: all four of Voyager 1's trajectory correction maneuver (TCM) thrusters are used for the first time since November 1980. This will allow Voyager 1 to continue to transmit data for longer.
- November 5, 2018: Voyager 2 crosses the heliopause, departing the heliosphere. Both Voyagers are now in interstellar space.
Artist's impression of Voyager 1 passing the rings of Saturn in 1980.
Credit: NASA/Hulton Archive/Getty Images
While both Voyagers have now left the heliosphere, that doesn't mean they're outside the solar system yet. The latter is defined as the vastly larger region of space, populated by all the bodies that orbit the Sun. The limit of the Solar system is the outer edge of the Oort cloud.
As available power declined, more and more of the Voyager 1's instruments and systems have been turned off – prioritising the instruments that send back data on the heliosphere and interstellar space. It is expected that the last instruments will cease operation sometime between 2025 and 2030.
Travelling at just about 61,200 km/h (38,000 mph) relative to the Sun, the craft will need 17 and a half millennia to cover the distance of a single light year. Proxima Centauri, the closest star to the Sun, is 4.2 light-years away. If Voyager 1 were going in that direction, it would need almost 74 millennia to get there. But it isn't. So, what is next?
- In 2024, NASA plans to launch the Interstellar Mapping and Acceleration Probe (IMAP), which will build on Voyager's observations of the heliopause and interstellar space.
- In about 300 years, Voyager 1 will reach the inner edge of the Oort Cloud.
- In about 30,000 years, it will exit the Oort Cloud – finally leaving the solar system altogether.
- In about 40,000 years, it will pass within 1.6 light-years of Gliese 445, a star in the constellation Camelopardalis.
- In about 300,000 years, it will pass within less than 1 light-year of the star TYC 3135-52-1.
- According to NASA, Voyagers 1 and 2 "are destined – perhaps eternally – to wander the Milky Way."
Blind Willie in space
Flying on board Voyagers 1 and 2 are identical 'golden' records, carrying the story of Earth far into deep space.
Credit: NASA, public domain
Both Voyager 1 and 2 carry a Golden Record that contains pictures, scientific data, spoken greetings, a sampling of whale song and other Earth sounds, and a mixtape of musical favorites, from Mozart to Chuck Berry.
Perhaps in a distant future and place, some alien intelligence with a record player will have a listen to Blind Willie Johnson hum Dark Was the Night, Cold Was the Ground, and think of us: "What a strange old planet that must have been."
Strange Maps #1065
Got a strange map? Let me know at firstname.lastname@example.org.
- Hasta La Vista, Voyagers - Big Think ›
- Carl Sagan's 'Sounds of Earth' Golden Voyager Record May Soon ... ›
- Voyager 1 Isn't Done Surprising Us Yet - Big Think ›
Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.
- 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>
Researchers figure out the average temperatures of the last ice age on Earth.
- A new study analyzes fossil data to find the average temperatures during the last Ice Age.
- This period of time, about 20,000 years ago, had the average temperature of about 46 degrees Fahrenheit (7.8 C).
- The study has implications for understanding climate change.
Surface air temperatures during the last ice age.
Credit: Jessica Tierney, University of Arizona
"The Expanse" is the best vision I've ever seen of a space-faring future that may be just a few generations away.
- Want three reasons why that headline is justified? Characters and acting, universe building, and science.
- For those who don't know, "The Expanse" is a series that's run on SyFy and Amazon Prime set about 200 years in the future in a mostly settled solar system with three waring factions: Earth, Mars, and Belters.
- No other show I know of manages to use real science so adeptly in the service of its story and its grand universe building.
Credit: "The Expanse" / Syfy<p>Now, I get it if you don't agree with me. I love "Star Trek" and I thought "Battlestar Galactica" (the new one) was amazing and I do adore "The Mandalorian". They are all fun and important and worth watching and thinking about. And maybe you love them more than anything else. But when you sum up the acting, the universe building, and the use of real science where it matters, I think nothing can beat "The Expanse". And with a <a href="https://www.rottentomatoes.com/tv/the_expanse" target="_blank">Rotten Tomato</a> average rating of 93%, I'm clearly not the only one who feels this way.</p><p>Best.</p><p>Show.</p><p>Ever. </p>
Contrary to what some might think, the brain is a very plastic organ.
As with many other physicians, recommending physical activity to patients was just a doctor chore for me – until a few years ago. That was because I myself was not very active.