The Knowledge
🚦 Who Really Invented the Modern Traffic Light?
The modern traffic light, largely attributed to Garrett Morgan’s 1923 invention, introduced a critical yellow warning light that improved public safety. Despite his significant impact on traffic systems, Morgan’s contributions have often been overlooked due to historical racism.
Last Updated on February 14, 2026 by Daily News Staff
When you think about the traffic light, you probably picture green for go, red for stop, and maybe a frustrated glance at the yellow. But have you ever stopped to ask: Who actually invented this system we take for granted every day?
The story of the modern traffic light isn’t just about technology—it’s about innovation, public safety, and a Black inventor named Garrett Morgan who changed the way we move through the world.
🔦 Early Traffic Signals: A Dangerous Beginning
Before cars dominated streets, early attempts at traffic control involved manual policing and hand signals. In 1868, the first gas-powered traffic signal was installed in London outside the British Houses of Parliament. Designed by J.P. Knight, a railway engineer, this early signal exploded after just a month due to a gas leak—killing a police officer and abandoning the idea for years.
As cars became more common in the early 20th century, so did traffic jams—and accidents. Cities needed a safer, more efficient solution.
🛠️ Enter Garrett Morgan
In 1923, Garrett Morgan, an African-American inventor and entrepreneur from Cleveland, Ohio, received U.S. Patent No. 1,475,024 for a traffic control device that added a crucial feature: a “warning position” between stop and go. This idea is the basis for today’s yellow light.
His signal was:
- Manually operated
- T-shaped
- Designed to be mounted on a post
- And included a buffer phase to clear intersections before switching direction
This innovation was not only about traffic flow—it was about safety and preventing collisions at a time when automobile fatalities were rapidly increasing.
Morgan sold the rights to his invention to General Electric for $40,000 (equivalent to over $700,000 today), though his contributions were overlooked for decades.
👉 View the full patent on Google Patents
⚙️ Was Morgan the
Only
Inventor?
No. Traffic signal history has multiple contributors:
- Lester Wire, a Salt Lake City policeman, created an electric traffic light prototype in 1912.
- William Ghiglieri patented an automatic signal in 1917.
- Garrett Morgan’s version stood out for its practical innovation—the transitional phase—and for being one of the first widely adopted and commercially viable versions.
In other words, Morgan helped move the traffic light from an experimental device to a nationwide safety standard.
🎥 Watch the Story in 60 Seconds
We break this story down in our latest Forgotten Genius Fridays episode from The Knowledge series on STM Daily News.
📺 Watch “Who Really Invented the Modern Traffic Light?” here: https://youtu.be/cS-emlzhjjk
✊ Why Garrett Morgan Deserves More Recognition
Garrett Morgan’s impact goes far beyond traffic lights. He also invented a gas mask used by firefighters and soldiers, and he launched one of the first Black-owned newspapers in the U.S.
He was a true innovator, working in an era where his contributions were often ignored due to racism. Today, we honor his legacy by telling his story and recognizing how his vision saved countless lives.
🧠 Now you know.
— STM Daily News
Dive into “The Knowledge,” where curiosity meets clarity. This playlist, in collaboration with STMDailyNews.com, is designed for viewers who value historical accuracy and insightful learning. Our short videos, ranging from 30 seconds to a minute and a half, make complex subjects easy to grasp in no time. Covering everything from historical events to contemporary processes and entertainment, “The Knowledge” bridges the past with the present. In a world where information is abundant yet often misused, our series aims to guide you through the noise, preserving vital knowledge and truths that shape our lives today. Perfect for curious minds eager to discover the ‘why’ and ‘how’ of everything around us. Subscribe and join in as we explore the facts that matter. https://stmdailynews.com/the-knowledge/
The Knowledge
Metrolink Offers Fare-Free Rides for Earth Day 2026 Across Southern California
Metrolink offers fare-free rides for Earth Day 2026 across Southern California, encouraging sustainable travel and reduced emissions.
Last Updated on April 21, 2026 by Daily News Staff
Metrolink Offers Fare-Free Rides for Earth Day 2026
LOS ANGELES — April 22, 2026 — In a continued push toward sustainable transportation, Metrolink will once again offer systemwide free rides on Earth Day, inviting commuters and travelers to leave their cars behind and explore a cleaner way to move across the region.
A One-Day Opportunity to Ride Free
On Wednesday, April 22, passengers can board any Metrolink train — including the Arrow service — without purchasing a ticket. The initiative is part of the broader celebration of Earth Day, encouraging environmentally conscious travel choices.
The fare-free program is designed to appeal to both regular riders and first-time users, particularly those navigating Southern California’s persistent traffic congestion and rising fuel costs.
Encouraging Sustainable Travel Habits
“Earth Day is a reminder that small changes, like choosing public transit over driving one day a week, can have a meaningful impact on our environment,” said Doug Chaffee, chair of the Metrolink Board.
With gas prices continuing to strain household budgets, the agency hopes the initiative will inspire more residents to consider rail as part of their regular commute.
Regional Connections Expand Access
Metrolink’s Earth Day promotion aligns with similar efforts by other Southern California transit providers. Riders can seamlessly connect to services operated by: LA Metro and the Orange County Transportation Authority, Riverside County Transportation Commission, San Bernardino County Transportation Authority and Ventura County Transportation Commission.
These partnerships extend the reach of fare-free travel across a six-county region, making it easier for riders to explore destinations without relying on personal vehicles.
Service Adjustments and Rider Tips
Passengers should note that trains will operate on a reduced weekday schedule, implemented earlier this spring. Despite the adjustment, all Metrolink lines and station cities remain in service.
For those planning a trip:
- No ticket is required — simply board the train
- Bikes are welcome, with capacity ranging from three bikes per standard car to nine in designated bike cars
- A curated destination guide highlights attractions within walking or biking distance of stations
Environmental and Economic Impact
Metrolink is also promoting its Personal Impact Calculator, a digital tool that allows riders to estimate how switching from driving to rail can reduce greenhouse gas emissions and lower fuel expenses.
A Broader Trend in Public Transit
Fare-free transit days have gained traction nationwide as agencies look to boost ridership and promote sustainability. Southern California’s expansive commuter rail network makes it particularly well-suited for such initiatives, offering a viable alternative to one of the country’s most car-dependent regions.
Bottom Line
Metrolink’s Earth Day promotion is more than a one-day free ride — it’s a strategic effort to shift commuter behavior, reduce environmental impact, and showcase the convenience of regional rail. For Southern Californians, April 22 presents a low-risk opportunity to rethink how they travel.
Source: Metrolink
https://metrolinktrains.com/news/metrolink-goes-fare-free-for-earth-day-on-april-22
Dive into “The Knowledge,” where curiosity meets clarity. This playlist, in collaboration with STMDailyNews.com, is designed for viewers who value historical accuracy and insightful learning. Our short videos, ranging from 30 seconds to a minute and a half, make complex subjects easy to grasp in no time. Covering everything from historical events to contemporary processes and entertainment, “The Knowledge” bridges the past with the present. In a world where information is abundant yet often misused, our series aims to guide you through the noise, preserving vital knowledge and truths that shape our lives today. Perfect for curious minds eager to discover the ‘why’ and ‘how’ of everything around us. Subscribe and join in as we explore the facts that matter. https://stmdailynews.com/the-knowledge/
Space and Tech
I’ve fired one of America’s most powerful lasers – here’s what a shot day looks like
A lead scientist takes you inside the Texas Petawatt at UT Austin, where hours of careful alignment and safety checks build to a single, breath-holding laser shot that briefly creates star-like conditions in a vacuum chamber.
Ahmed Helal, The University of Texas at Austin
If you walk across the open yard in front of the Physics, Math and Astronomy building at the University of Texas at Austin, you’ll see a 17-story tower and a huge L-shaped building. What you won’t see is what’s underneath you. Two floors below ground, behind heavy double doors stamped with a logo that most students have never noticed, sits one of the most powerful lasers in the United States.
I was the lead laser scientist on the Texas Petawatt, or TPW as we called it, from 2020 to 2024. Texas Petawatt, which is currently closed due to funding cuts, was a government-funded research center where scientists from across the country applied for time to use specialized equipment. It was part of LaserNetUS, a Department of Energy network of high-power laser labs.
This type of laser takes a tiny pulse of light, stretches it out so it doesn’t blast optics to pieces, and amplifies it until, for a brief instant, it carries more power than the entire U.S. electrical grid. Then it compresses the pulse back to a trillionth of a second to create a star in a vacuum chamber.
On a typical shot day, the target might be a piece of metal foil thinner than a human hair, a jet of gas or a tiny plastic pellet – each designed to answer a different scientific question.
Scientists from across the country applied for time on TPW to study everything from the physics of stellar interiors and fusion energy to new approaches for cancer treatment.
Most people hear about petawatt lasers and picture something out of a movie. A “shot day” is actually hours of quiet, repetitive work followed by about 10 seconds where nobody breathes.
I now work as a research scientist at the University of Texas-Austin, studying the interaction of lasers with different materials, but a typical shot day during my time running TPW would look like this:
7 a.m.
I arrive two hours before the first scheduled shot. I put on my gown, boots and hairnet and step into the cold clean room. The laser doesn’t just turn on. You coax it awake.
I start with the oscillator, a small box that generates the first seed of light. I write down the parameters that define how the laser will behave during the shot: energy, center frequency, vacuum pressure in the tubes, cooling water level and flow. At this stage, they are fixed regardless of the experiment. The laser must perform the same way every time before the science can begin. Then I fire up the pump laser that will amplify this tiny pulse from nanojoules to about half a joule.
The system needs at least 30 minutes to stabilize. During that time, I check alignment through every pinhole and every camera along the beam path. A slight misalignment at this stage isn’t just a problem; it can be catastrophic – a mispointed beam at full power can burn through optics that take months to source and replace, setting the entire laser back.
Building the beam
Once the system is warmed up, I send the beam into the first amplifier: a glass rod surrounded by bright flash lamps that pump light into the glass – like charging a battery. With each pass, the beam absorbs energy from the glass and grows stronger. Then the beam travels into a larger rod, where it makes four passes, picking up more energy each time until it reaches about 12 joules, roughly the energy of a ball thrown hard across a room.
This process alone takes the better part of an hour, most of it spent checking and confirming alignment and energy at each stage.
I expand the beam and send it through the final stage: the disk amplifiers. Two amplifiers, each consisting of two massive 30-centimeter glass disks, are pumped by a huge bank of flash lamps powered by capacitor banks – essentially giant batteries that store electrical energy and release it in a sudden burst. They are so large that they have their own room on a separate floor. Fast optical shutters between each stage act as gates, controlling exactly when and where the beam travels.
The shot
When the experimental team confirms that the target is in position, it asks me to prepare for a system shot. I run through the long checklist. We test the shutters and switch to system shot mode. Every monitor in the facility changes to display the same message – “System Shot Mode” – and flashes red.
I lean into the microphone at the control desk, a vintage piece that looks like it belongs in a World War II radio room, and announce that we’re going into a system shot. Then I open the compressor beam dump: a heavy glass plate that normally blocks the beam from reaching the target. It takes about two minutes to move.
“Sweeping, sweeping for a system shot.”
The announcement goes out over speakers across the facility. I grab a small interlock key, put on my laser safety goggles and head downstairs. I walk a specific pattern through every room, checking that nobody is still inside. As I go, I lock each door with the key. If anyone opens one of those doors after I’ve locked them, the entire shot sequence aborts.
Back in the control room, I sit down and start charging the capacitor banks. At this point, there’s no going back except for an emergency shutdown, and that means losing the shot and waiting for everything to cool down.
“Charging.”
The room goes silent. Everyone’s eyes are on the monitors. Nobody talks.
I typically will share a glance with the researcher whose project the shot is for – today it’s Joe, a visiting scientist from Los Alamos National Lab, who designed the target we’re about to vaporize. He’s gripping his coffee cup like it owes him money. I turn back to the console.
“Charge complete. Firing system shot in three, two, one. Fire.”
I press the button. A loud thud rolls through the building as all that stored energy dumps into the beam. The monitors freeze, capturing everything at the moment of the shot: beam profiles, spectra, diagnostics – these metrics provide a full picture of exactly how the laser performed and whether the shot was clean. Downstairs, in the vacuum chamber, a spot smaller than a human hair just reached temperatures measured in millions of degrees.
I lean back in my chair and start recording laser parameters as everyone exhales. A radiation safety officer heads down first to check readings around the target chamber before anyone else can enter. The experimental team follows to collect data.
Sometimes it all works perfectly. Sometimes a shutter fails to open and you lose the shot.
For example, one afternoon in 2023, we’d spent three hours preparing for a high-priority shot. Target aligned. Capacitors charged. I pressed the button and heard nothing. A shutter had failed somewhere in the chain. The monitors stayed frozen, showing black. Nobody said anything. I wrote SHOT FAILED in the logbook and started the hourlong cooldown sequence. That’s the part they don’t show in movies: sitting in silence, waiting to try again. We got the shot four hours later.
This anticipation is all part of the job: hours of patience for 10 seconds you never quite get used to. Everything happens underneath a campus where thousands of people walk above, unaware that for a fraction of a second, a tiny point of matter hotter than the surface of the Sun just existed below their feet.
Ahmed Helal, Research Scientist, The University of Texas at Austin
This article is republished from The Conversation under a Creative Commons license. Read the original article.
The science section of our news blog STM Daily News provides readers with captivating and up-to-date information on the latest scientific discoveries, breakthroughs, and innovations across various fields. We offer engaging and accessible content, ensuring that readers with different levels of scientific knowledge can stay informed. Whether it’s exploring advancements in medicine, astronomy, technology, or environmental sciences, our science section strives to shed light on the intriguing world of scientific exploration and its profound impact on our daily lives. From thought-provoking articles to informative interviews with experts in the field, STM Daily News Science offers a harmonious blend of factual reporting, analysis, and exploration, making it a go-to source for science enthusiasts and curious minds alike. https://stmdailynews.com/category/science/
Science
New Glenn’s Third Mission Set for April 19 as Blue Origin Advances Commercial Space Capabilities
CAPE CANAVERAL, Fla. — Blue Origin has confirmed the launch window for the third mission of its heavy-lift New Glenn rocket, marking another step forward in the company’s expanding role in commercial spaceflight.
New Glenn’s Third Mission
Launch Details and Timeline
The mission is scheduled to lift off no earlier than Sunday, April 19, 2026, from Launch Complex 36 at Cape Canaveral Space Force Station. The two-hour launch window opens at 6:45 a.m. EDT (10:45 UTC) and closes at 8:45 a.m. EDT (12:45 UTC).
Viewers can follow the mission through a live webcast hosted by Blue Origin, beginning approximately 30 minutes before liftoff.
Mission Payload: Expanding Space-Based Connectivity
At the heart of the mission is the deployment of the BlueBird 7 satellite, developed by AST SpaceMobile. The satellite is designed to enhance a growing direct-to-smartphone broadband network, an emerging technology aimed at delivering connectivity to standard mobile devices without the need for ground-based towers.
BlueBird 7 will contribute to expanding network capacity and is expected to support initial service rollout plans targeted for 2026. The broader initiative reflects a significant shift in how satellite infrastructure could complement terrestrial telecom systems, particularly in underserved or remote regions.
Reusability Milestone: Booster Returns Again
A key feature of this mission is the planned reuse of New Glenn’s first-stage booster, “Never Tell Me The Odds.” The booster previously demonstrated a successful launch and landing during the rocket’s second mission in November, underscoring Blue Origin’s commitment to reusable rocket technology—a cornerstone of cost reduction and operational efficiency in modern spaceflight.
If successful, this mission will further validate the reliability of the New Glenn system and strengthen its competitiveness in a market increasingly shaped by reusable launch vehicles.
Industry Context: Competing in a Rapidly Evolving Market
The New Glenn program represents Blue Origin’s answer to heavy-lift launch demands, positioning the company alongside major players such as SpaceX. As satellite constellations grow in scale and ambition, reliable and cost-effective launch services have become a critical component of the global space economy.
The inclusion of commercial payloads like BlueBird 7 highlights the increasing collaboration between aerospace firms and telecommunications providers, signaling a future where space-based infrastructure plays a central role in everyday connectivity.
Looking Ahead
With its third mission, New Glenn continues to build momentum as a next-generation launch platform. The combination of reusable hardware, commercial partnerships, and advanced payload capabilities places this launch among the most closely watched developments in the 2026 spaceflight calendar.
For ongoing updates, mission tracking, and live coverage, audiences can follow Blue Origin across its digital platforms or visit its official website.
Source
Blue Origin Official Announcement – New Glenn Third Mission
Related External Links
- Learn More About Blue Origin’s New Glenn Rocket
- AST SpaceMobile – Space-Based Cellular Broadband Network
- Cape Canaveral Space Force Station Information
- NASA Overview of Low Earth Orbit (LEO) Operations
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