The first practical silicon solar cell was developed at Bell Labs

The first rooftop solar panels were installed in 1883

In 1883, New York inventor Charles Fritts created the first solar cell by coating selenium with a thin layer of gold. The cell achieved energy conversion rates of 1 to 2% compared to the 15 to 20% of modern photovoltaics.

Solar panel manufacturing begins with silicon extracted from sand

The silicon is purified and shaped into wafers less than 0.2 millimeters thick, coated and connected through a criss-cross pattern of narrow and wider metal, followed by multiple rounds of lamination before bonding to a weatherproof panel.

The first lithium-ion battery was invented at ExxonMobil

Initially a side project that became a priority due to the 1973 oil crisis, the battery's flammability risks and manufacturing challenges, along with the waning crisis, led the company to shut down its battery program. Other researchers would gradually improve upon published prototype designs in the next decade.

Light energy can be transformed into electricity in solar cells via the photovoltaic effect

When light strikes semiconducting material, it can knock electrons out of atoms, creating a charge imbalance within the material. A wire connecting the oppositely charged regions can allow electrons to flow back, balancing the charges and producing an electric current that can be harnessed to power devices.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

Tracing the evolution of mobile phones

The first cell phone was created in 1973, with a 2.4-pound handset and a battery life of about 30 minutes. Since then, pretty much everything about it has drastically changed, with more than 5 billion cellphone users across the globe (that's more than half of the world population). Learn about the evolution of the mobile phone and where the technology may go in the future with this four minute video.

Sand 'batteries' can store excess electricity from the power grid as thermal energy

Energy collected from solar or wind power is used to heat insulated silos full of sand to temperatures as high as 450 degrees Celsius (842 degrees Fahrenheit), which can be retained for long periods. These thermal energy storage systems can be designed to boil water and generate electricity when needed.

The world's largest lemon battery was made from nearly 3,000 lemons

By connecting lemons with a piece of zinc on one side and a piece of copper on the other, a team from the Royal Society of Chemistry created a fruit battery with a capacity of 2,307.8 volts.

The world's first geothermal power plant was built in 1913 in Devil's Valley

In Tuscany, Italy, Prince Piero Ginori-Conti of Trevignano established the plant nine years after creating a generator that powered five light bulbs using steam vents in the area. Within three years, a second plant was built with two generators, each with 10 times the energy output of the first.

Silicon must be 99.9999999% pure to be used in creating microchips

After the mined quartz is processed in an electric-arc furnace to remove oxygen from the silica, it undergoes the Siemens process, where it is bathed in hydrochloric acid. The liquid produced in the reaction undergoes multiple distillations to produce ultra-pure silicon in the end.

Space-based solar power systems may beam energy to Earth

Researchers have successfully collected power from solar panels on a plane and transmitted it to a receiver on Earth's surface, achieving a milestone for space-based energy. The proof of concept is a precursor for a satellite-based solar farm that would transmit energy 24 hours a day.

The first computers performed calculations using lightbulb-like tubes

Before transistors, the first electronic computers relied on vacuum tubes—components that switched signals on and off. Despite machines like ENIAC—the first programmable, general-purpose, electronic computer—utilizing nearly 18,000 tubes that generated massive amounts of heat and frequent failures, they laid the foundation for modern computing hardware.

View an interactive chart of energy conversion efficiencies for various photovoltaics

This National Renewable Energy Laboratory visualization provides maximum confirmed efficiencies for nearly 30 research PV cell technologies from August 1975 to today. Concentrator multi-junction cells have led the field since 1993. (Desktop recommended site.)

Before Silicon Valley, the American innovation hub was New Jersey

Today, Silicon Valley is known for its dominance in the tech world. But before it rose to prominence, New Jersey was the country's innovation hub. From Thomas Edison's light bulb to the transistor, New Jersey was considered the nation's leader in technology.

The team responsible for the first interplanetary sundials included Bill Nye

While reviewing designs for instruments to be carried by future Mars rovers, Nye suggested adapting the function of a calibration tool, which would be used by the Spirit and Opportunity rovers to help calibrate the brightness and color of their panoramic cameras on the Martian surface.

The world's first commercial biological computer combines neurons with silicon

Australian start-up Cortical Labs unveiled CL1, a hybrid chip designed to help scientists study brain function in real-time. The 800,000 lab-grown neurons on the chip are kept viable for six months via a built-in life support system.

Sony set the standard for cylinder-shaped batteries when it repurposed manufacturing equipment used to make rolls of magnetic recording tape.

How scientists discovered helium from sunlight over a decade before seeing it on Earth

In 1868, using tools that dispersed light into its constituent colors like a prism, astronomers Pierre Jules César Janssen and Joseph Norman Lockyer independently identified a bright yellow line in the solar spectrum that didn't match any known element. Fourteen years later, amid continued skepticism over the existence of a new element, the same spectral signature was observed in lava on Earth.

Pierre Curie found electricity could be generated by compressing certain crystals

Jacques and Pierre Curie discovered the piezoelectric effect in 1880. Pierre incorporated it into an apparatus used by Marie Curie to discover polonium and radium. This phenomenon is seen in barbecue lighter ignition mechanisms, where quartz is struck to create a spark that ignites fuel.

Jonas Salk developed the first successful polio vaccine—and tested it on himself

The American medical researcher developed the inactivated virus vaccine from 1952 to 1955 and proved that it could prevent disease. He tested the virus on himself and his family in 1954 and then carried out formal clinical trials on more than 1.3 million children.

Evidence suggests the first cells on Earth were bacteria

About 4 billion years ago, these single-celled organisms harvested carbon dioxide and sunlight to produce their own food and oxygen, setting the stage for the evolution of oxygen-breathing life forms. Archaeabacteria, which thrive on inorganic molecules in extreme habitats on Earth today, were also among the earliest organisms.

The first smartwatch was made by Microsoft in 1994

Coproduced by Timex, the Timex DataLink 150 featured a small LCD screen and could transfer data to and from a Windows PC. Like the Windows XP Tablet that launched in 2002, the smartwatch did not sell well, and both products are considered to have been released before their time.

Thomas Edison, eager to communicate with ghosts, tinkered with an apparatus called the 'spirit phone'

The inventor was interested in developing a scientific method for communicating with the dead. He was not interested, though, in the occult figures who believed the dead could be reached through Spiritualism, which he found childish. He believed those kinds of people "permit themselves to become, in a sense, hypnotized into thinking that their imaginings are actualities."

Watch how Sanger sequencing kickstarted the first generation of DNA sequencing

Sanger sequencing is a foundational DNA sequencing technology developed in 1977. The Nobel Prize-winning discovery uses fluorescent dyes at the end of DNA chains, which are sorted by length through electrophoresis, to determine the order of nucleotide bases.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

Credit for inventing the laser was fought over for nearly three decades

Although Theodore Maiman built the first working laser in 1960, Gordon Gould coined the term earlier. Charles Townes and Arthur Schawlow of Bell Labs filed a patent after Gould came up with the idea and name, but before Gould filed his patent.

Saccharin was widely used in WWI when sugar was rationed

The substance was discovered by chemists in 1878, but its use became more common during World War I and also afterward as a result of sugar rationing. It had become a typical household item in the US and Europe by 1917. During World War II, the artificial sweetener again saw significant popularity.

In its famous catalog, Sears sold $600 DIY house kits from 1908 through the 1940s, resulting in an estimated 100,000 'Sears and Roebuck homes.'

The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

Learn more about the history of fireworks, which dates back to an accidental invention during an alchemist's quest for information about immortality.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

Visualize the path of every solar eclipse from 1900 to 2099 and see what each looks like when observed from different locations on Earth.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

Planeterrellas create artificial auroras that mimic the atmospheric displays of light by setting up an electric field between two metal balls in a jar filled with a small amount of air.

While the first exchange-traded fund (a 'basket' of different assets that can be bought and sold on a stock exchange) in the US only launched in 1993, the global ETF market has grown to more than $10T in the short time since.

The first horror movie is believed to be George Méliès' 1986 short 'The Haunted Castle,' which pioneered the use of special effects

English mathematician Ada Lovelace wrote the first computer algorithm a century before computers existed and hypothesized that computing devices would one day be able to compose music—foreseeing the generative AI systems of today.

SpaceX's S-1 or 'prospectus' revealed many previously unknown details about the company, including its unprofitability despite doing $18.7B in revenue in 2025, exactly how many voting shares Elon Musk will have in the company (roughly 85%), and more.

Radioactive elements can introduce software errors because the ionizing radiation they produce can detach electrons from atoms, and computer code relies on the distribution of electrons.

The animatronic shark from Steven Spielberg's 'Jaws,' the first modern blockbuster, was a complex underwater apparatus called 'Bruce.'

Some researchers have labeled nomophobia, the fear of being without your phone, as 'the phobia of the 21st century.'

Brian Wilson wrote the Beach Boys' 'Don't Worry Baby' for the Ronettes, but the legendary girl group rejected it.

The word 'jazz' evolved from 'jasm,' 19th-century American slang for 'energy'

An investigation suggests a Scottish island became awash in forever chemicals via seafoam and seaspray—raising questions about what that means for the safety of other coastal areas.

Legendary architect Frank Lloyd Wright designed the SC Johnson headquarters in Wisconsin, aiming to make a cathedral-like workplace

Salvador Dalí believed he was his own dead brother, who had died nine months before he was born

Pure water does not conduct electricity because this flow of energy requires the movement of charged particles, and water is a neutral molecule.

For centuries, it was common to sleep in two shifts: a few hours at the beginning of the night, and a longer period beginning around midnight