English cosmologist Stephen Hawking (1942-2018) jokes about alien sightings

With his dry wit, Stephen Hawking warns of AI dangers and explains imaginary time

In this comedic interview with John Oliver, Stephen Hawking discusses his groundbreaking work in theoretical physics, his views on AI, and Oliver's chances of dating Charlize Theron in the multiverse—all with his trademark voice and humorous tone.

A blend of brilliance and humor made Stephen Hawking's cameos unforgettable

Throughout his life, he appeared in numerous pop culture moments—from "The Simpsons" to "The Big Bang Theory"—showing his talent for comedy and his love of science outreach. He was the only person to play himself on "Star Trek: The Next Generation," even writing some of his own lines.

Stephen Hawking on the need to explore space

Should we be content with being cosmic couch potatoes? In this interview, the late Professor Stephen Hawking lays out the case for continued and increased human space exploration, despite its cost and challenges.

Statistically speaking, aliens likely exist, but we still haven't found any evidence of them

The Fermi paradox addresses this discrepancy between the lack of evidence of alien life despite the high likelihood of its existence. Physicist Brian Cox offers various theories, like the extinguished civilizations hypothesis, for why we have never found any extraterrestrial neighbors.

No one showed up to the party for time travelers organized by Stephen Hawking

In 2009, Hawking hosted a reception but only sent out invitations afterward, hoping that time travelers from the future would attend and prove time travel possible. He later joked it was "experimental evidence" that time travel doesn’t exist.

Listen to a podcast exploring reported UFO and alien sightings

From the most shocking accounts of abductions and UFO sightings to an interview with a Harvard professor about these claims, dive into fascinating stories about run-ins with ETs that have continued to be told for decades.

Hawking suggested studying black holes could reveal truths about the universe's start

After predicting black holes could evaporate and before undergoing a tracheotomy, Stephen Hawking conducted interviews in his voice, explaining phenomena like black holes and the Big Bang. In this clip, he explains how curiosity drives humans to become “masters of the universe.”

Despite his disability, Stephen Hawking reshaped our understanding of black holes

His theoretical work—especially on black holes emitting radiation, now known as Hawking radiation—challenged long-held ideas. He also brought complex physics to the public through bestselling books like "A Brief History of Time."

A scientist debunks theories for why aliens might invade Earth

While TV and films offer common tropes for why aliens would invade Earth, many of those reasons aren't actually feasible. For example, a species with technology advanced enough to allow it to travel between planets likely doesn't need to enslave flawed humans to carry out its labor.

According to his daughter, Stephen Hawking defied early doubts about his intellect

Lucy Hawking details what it was like to be the daughter of the famed cosmologist and what his life looked like from her eyes. Among the anecdotes was Stephen's enjoyment of being on "The Simpsons" because production gave him a wheelchair with helicopter blades.

UFO sightings taken seriously by the US government

As UFOs make a resurgence in public awareness, take a trip back to the early decades of UFO research. This interactive shows the location and descriptions for some of the most fascinating incidents reported to a secretive Air Force team between 1947...

Stephen Hawking's final message

Famous cosmologist Stephen Hawking—who lived for half a century after being diagnosed with Lou Gehrig's disease—delivered a final speech just before he died in 2018. In the video, Hawking talks about the importance of science and reason in...

Stephen Hawking's condition explained

Diagnosed with ALS at 21 and told he had two years to live, Stephen Hawking went on to change our understanding of black holes and the universe, living 55 more years and defying every expectation.

If aliens visited Earth, it seems unlikely they'd be evolved biological creatures like us

The writer behind Mindless Algorithm, George McGowan, challenges various assumptions about aliens depicted in science fiction. One of those is that aliens are, like humans, individual entities that live, age, and die. McGowan suggests that the difficulty of intergalactic travel and the aliens' technological advancements make it more likely that they'd be an advanced form of AI or digital copies of biological entities.

What Stephen Hawking said about time travel

When renowned theoretical physicist Stephen Hawking did not rule out the possibility of time travel in his posthumous book Brief Answers to the Big Questions, many hopefuls got excited. But, unfortunately for them, Hawking believed that yet-to-be discovered laws of physics will prove time travel impossible. This piece outlines some practicalities about the speed of light and wormholes that lend way to Hawking’s prediction.

Using scientific bets, Hawking challenged and highlighted major physics ideas

Hawking famously placed wagers on high-stakes questions in theoretical physics—such as the Higgs boson—for fun and to draw attention to science. When Hawking lost a bet about Cygnus X-1 being a black hole, he paid up with a magazine subscription.

Humans have speculated about alien life since ancient times

Around 50 B.C.E., Roman poet and philosopher Lucretius shared the idea that alien life was possible, which was put forth by Greek philosopher Epicurus. The writing is believed to be the first straightforward assertion in Western literature that aliens must exist.

Journalist Payne Lindsey examines reports on UFOs

The Pentagon made a splash in recent years with revelations of videos showing fighter pilots observing unknown aerial objects. Lindsey uncovers stories of still-unverified UFO sightings and addresses the likely possibility of life beyond Earth.

Quantum mechanics-based technology may explain the Fermi paradox

It describes the discrepancy between the high likelihood of life beyond Earth given the vastness of the universe and the lack of evidence for such life, since extraterrestrial civilizations have not communicated with us. However, quantum communication—a more information-dense and effective method than classical means—requires massive receivers and very narrow signals, which would easily miss Earth, making a lack of signals expected.

A 1947 news story about a pilot observing UFOs inspired an uptick in reports of 'flying saucers,' even though the pilot himself never used that description.

A quote by Howard Hughes

"Do the impossible, because almost everyone has told me my ideas are merely fantasies."

How Stephen Hawking’s voice became iconic

Stephen Hawking relied on a voice synthesizer after losing the ability to speak due to complications with ALS. Despite technological advances, he refused to change the "Perfect Paul" voice, making it a cornerstone of his public identity.

The most mysterious (known) star in the universe

Something massive, with roughly 1,000 times the area of Earth, is blocking the light coming from a distant star known as KIC 8462852. One of astronomers' more intriguing theories: Alien technology. Discovered via NASA's Kepler space telescope and a...

Humans tend to imagine aliens as humanlike, but that's probably unlikely. Three different hypothetical planets show how aliens' bodies could take many forms.

Stephen Hawking's children's books help make science fun and accessible for kids

Stephen Hawking co-wrote "George’s Secret Key to the Universe" with his daughter, Lucy, to introduce young readers to big questions about the cosmos. In the first book, the protagonist rides a comet and discovers that black holes aren’t black.

Stephen Hawking's early rowing days shaped the bold persona for which he became known

Before gaining fame as a physicist, Hawking was a coxswain at Oxford, where the sport helped him find his social footing and develop leadership skills, even as his motor neuron disease began to emerge.

Stephen Hawking's biggest discovery—Hawking radiation—came from a major mistake

Hawking radiation may not have been discovered without Jacob Bekenstein first convincing Stephen Hawking that black holes follow the laws of thermodynamics. The graduate student showed that black holes could shrink, setting the stage for Hawking's most significant contribution.

Universal limit to technological development may prevent finding alien civilizations

Given the vastness of the Universe, detecting alien life may require technological progress beyond the limits of what is sociologically viable and physically possible. Although interstellar civilizations are unlikely, messaging techniques and probes may improve the odds of successful communication with other intelligent life.

The Big Bang became physically plausible thanks to Stephen Hawking’s thesis

Stephen Hawking's PhD thesis mathematically showed that singularities—points of no volume and infinite density—are an expected feature of nature. It laid the theoretical groundwork for a model of the universe where everything originates from a single point.

See how distant aliens could preemptively strike humanity

Could aliens destroy us from light-years away? The team at Kurzgesagt imagines the impact of a highly sophisticated alien civilization setting out to crush humanity and considers the real-world logistics for warfare conducted across the Universe.

Cygnus X-1 helped scientists confirm black holes are real and measurable phenomena

The 1964 discovery of Cygnus X-1 provided the first strong candidate, but it took decades—and a famous bet between Stephen Hawking and Kip Thorne—before scientists were certain it was a black hole. Hawking's thumbprinted concession was delivered after breaking into Thorne's office.

Stonehenge has produced wild origin stories

Built before the wheel was invented, Stonehenge inspired increasingly fantastical explanations—from a 12th-century tale of Merlin and Nephilim giants to 1960s claims that aliens built it alongside the pyramids.

Neutron star collisions may be the universe's gold factories

In his last broadcast interview, Stephen Hawking comments on detecting gravitational waves from the collision of neutron stars. The event may serve as a new means of measuring cosmological distances and help identify revisions to general relativity.

Gravitational waves—ripples in spacetime that result from the motion of objects—were detected a century after Albert Einstein predicted their existence upon developing his theory of gravity.

Hawking radiation shows black holes slowly evaporate through quantum effects.

Hawking radiation is Stephen Hawking's theoretical prediction that black holes emit radiation and eventually evaporate. Applied to known black holes, their radiation is so weak that it would take vastly longer than the current age of the universe for them to disappear.

The creator of Sherlock Holmes published a book claiming fairies were real

In 1917, two young girls took photos of one another appearing to interact with fairies and a gnome. Sir Arthur Conan Doyle, author of the Sherlock Holmes books and a fervent believer in spiritualism, published the photos in a magazine and asked the girls to recreate them, which they did. Conan Doyle went on to write a book about the fairies. In 1983, decades after his death, the girls admitted the photos had been faked.

The first proposed experiment in the search for extraterrestrial intelligence (SETI) began with the mathematician and astronomer Carl Friedrich Gauss, who is credited with the idea of drawing a right triangle and three squares on Earth's surface to signal to aliens using the language of mathematics.

David Attenborough discusses creationism and his position as an agnostic

Attenborough argues that accounts of humanity's origins from different cultures cannot all be correct because they often differ, whereas geological records are consistent worldwide, meaning science provides the best understanding of the natural world. However, he acknowledges that, just as insects lack awareness of human goings-on, humans may be unaware of the existence of a deity.

One theory for why we haven't discovered aliens is that they haven't been born yet

There's a chance that human civilization arrived before any other life and aliens will soon emerge. If this is the case, there's also a chance for a competition to rule the Universe.

Ten underrated astronomy studies from 2022

The James Webb Space Telescope understandably received a lot of coverage in 2022. This astrophysicist wants to highlight ten major studies published last year you might have missed.

As of 2025, scientific evidence strongly supports 3I/ATLAS being a comet

Claims of alien technology would require the celestial object to transmit measurable technological signals, which were not detected by the world's largest fully steerable radio telescope. Previous telescope observations identified that 3I/ATLAS's chemical composition, structure, and orbital characteristics are consistent with those of an interstellar comet.

'There are no passengers on Spaceship Earth. We are all crew.'

- Philosopher Marshall McLuhan (1911-1980)

Nearly 50 years before the first observational evidence, a soldier fighting on the Eastern Front in World War I found a mathematical solution to Einstein's equations that suggested the existence of black holes.

New ways of seeing the cosmos have redrawn the map of human identity

From Galileo’s crude spyglass to the James Webb Space Telescope, each technological leap has expanded our observational reach and redefined philosophical and moral conceptions of our place in the universe. Identifying signs of life through the study of exoplanet atmospheres would represent the next great revolution.

'I don't know what you can say about a day when you see four beautiful sunsets.'

- Astronaut John Glenn (1921–2016)

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

The most bizarre numbers in the universe

Even for math-y types, some numbers are incomprehensible. This article dives into several kinds of numbers more complicated than even irrational numbers with endless decimals like "pi" or Euler's number: Noncomputable numbers. Read the bizarre...

Listen to the audiobook version of 'A Brief History of Time'

First published in 1988, Stephen Hawking's most famous novel has sold more than 25 million copies in 40 languages. Through non-technical terminology, Hawking discusses the nature of space and time, general relativity, quantum mechanics, gravity, black holes, and cosmology.

Neil deGrasse Tyson explains wormholes and black holes

Much of the film Interstellar is centered on the existence of a wormhole and black hole, which happen to be two of the most perplexing things in the universe. Astrophysicist and StarTalk Radio host Neil deGrasse Tyson explains how wormholes and black holes work in real life in this two-minute video.

Unpacking the famous argument in the 'Are We Living in a Computer Simulation?' paper

In 2003, philosopher Nick Bostrom published a paper in a journal arguing the technological possibility that humanity is living in a simulation. The argument, while popularly mocked (or cheered), is presented seriously in the paper. This podcast episode explores the contours of the arguments in an accessible way.