Interstellar Travel

Interstellar travel
Interstellar travel (

Interstellar travel is the hypothetical travel of spacecraft from one star system, solitary star, or planetary system to another. Interstellar travel is expected to prove much more difficult than interplanetary spaceflight due to the vast difference in the scale of the involved distances. Whereas the distance between any two planets in the Solar System is less than 30 astronomical units (AU), stars are typically separated by hundreds of thousands of AU, causing these distances to typically be expressed instead in light-years. Because of the vastness of these distances, non-generational interstellar travel based on known physics would need to occur at a high percentage of the speed of light; even so, travel times would be long, at least decades and perhaps millennia or longer.

As of 2022, five uncrewed spacecraft, all launched and operated by the United States, have achieved the escape velocity required to leave the Solar System as part of missions to explore parts of the outer system. They will therefore continue to travel through interstellar space indefinitely. However, they will not approach another star for hundreds of thousands of years, long after they have ceased to operate (though in theory the Voyager Golden Record would be playable in the event that the spacecraft is retrieved by an extraterrestrial civilization).

The speeds required for interstellar travel in a human lifetime far exceed what current methods of space travel can provide. Even with a hypothetically perfectly efficient propulsion system, the kinetic energy corresponding to those speeds is enormous by today's standards of energy development. Moreover, collisions by spacecraft with cosmic dust and gas at such speeds would be very dangerous for both passengers and the spacecraft itself.

A number of strategies have been proposed to deal with these problems, ranging from giant arks that would carry entire societies and ecosystems, to microscopic space probes. Many different spacecraft propulsion systems have been proposed to give spacecraft the required speeds, including nuclear propulsion, beam-powered propulsion, and methods based on speculative physics.

Humanity would need to overcome considerable technological and economic challenges to achieve either crewed or uncrewed interstellar travel. Even the most optimistic views forecast that it will be decades before this milestone is reached. However, in spite of the challenges, a wide range of scientific benefits are expected should interstellar travel become a reality.

Most interstellar travel concepts require a developed space logistics system capable of moving millions of tonnes to a construction / operating location, and most would require gigawatt-scale power for construction or power (such as Star Wisp– or Light Sail–type concepts). Such a system could grow organically if space-based solar power became a significant component of Earth's energy mix. Consumer demand for a multi-terawatt system would create the necessary multi-million ton/year logistical system.

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Voyager 2: Nasa fully back in contact with lost space probe

Nasa is back in full contact with its lost Voyager 2 probe months earlier than expected, the space agency said. In July a wrong command was sent to the spacecraft, sent to explore space in 1977, changing its position and severing contact.

Voyager 2: Nasa loses contact with probe after sending wrong command

Nasa has lost contact with its Voyager 2 probe billions of miles away from Earth after sending it the wrong command, the space agency has revealed. Last month, the spacecraft - exploring the universe since 1977 - tilted its antenna to point two degrees away from Earth after the mistake was made.

Can We Move PLANET EARTH Across the Universe?

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Voyager Hears Incredible Sounds of Interstellar Space

I wrote a foreword for this awesome Sci-Fi book here: Get a Wonderful Person shirt: Alternatively, PayPal donations can be sent here: Hello and welcome! My name is Anton and in this video, we will talk about

[1111.6131] The Fermi Paradox, Self-Replicating Probes, and the Interstellar Transportation Bandwidth

Title: The Fermi Paradox, Self-Replicating Probes, and the Interstellar Transportation Bandwidth Authors: Keith B. Wiley Abstract: It has been widely acknowledged that self-replicating space-probes (SRPs) could explore the galaxy very quickly relative to the age of the galaxy.

Generation ship

Since such a ship might take centuries to thousands of years to reach even nearby stars, the original occupants of a generation ship would grow old and die, leaving their descendants to continue traveling. Rocket pioneer Robert H.

Voyagers ride 'magnetic bubbles'

Humankind's most distant emissaries are flying through a turbulent sea of magnetism as they seek to break free of our Solar System.

Voyager: Still dancing 17 billion km from Earth

The most distant spacecraft from Earth, Voyager 1, is executing a series of roll manoeuvres, proving the 33-year-old explorer is in great shape. The extraordinary Voyager 1 spacecraft is demonstrating its nimbleness more than 30 years after leaving Earth.

Voyager-1 departs to interstellar space

When I sat down with the mission's project scientist in California in August 2012, his response was much the same as always: "My best estimate is that it will be in the next couple of years, but it may be in the next couple of days. It's unknown." Not anymore.

Pioneering Interstellar Flight - Tau Zero Foundation

The Tau Zero Foundation is dedicated to building the stepping stones that enable humankind to become a permanent, space-faring civilization.  Our members are passionate about practical interstellar flight and the adventures we encounter as we all work to achieve it. Ad astra incrementis.

Stars concoct complex molecules

Chemical factories around young stars may give rise to far more complex molecules than previously thought. Relatively complex, carbon-containing molecules are found in comets and on nearby planets, thought to have been made elsewhere in our Solar System.

Revel in the wonder of the Solar System

There are maps you can buy which show how light pollution blocks out the night skies. Look at the map for the UK, and English star-gazers have it the worst.

Project Longshot

Project Longshot was a conceptual interstellar spacecraft design. It would have been an uncrewed probe (about 400 tonnes), intended to fly to and enter orbit around Alpha Centauri B powered by nuclear pulse propulsion.[1]

Project Daedalus

Project Daedalus (named after Daedalus, the Greek mythological designer who crafted wings for human flight) was a study conducted between 1973 and 1978 by the British Interplanetary Society to design a plausible uncrewed interstellar probe.

Probe may have found cosmic dust

Scientists may have identified the first specks of interstellar dust in material collected by the US space agency's Stardust spacecraft. The Nasa spacecraft was primarily sent to catch dust streaming from Comet Wild 2 and return it to Earth for analysis.

Particles point way for Nasa's Voyager

Scientists working on Voyager 1 are receiving further data suggesting the probe is close to crossing into interstellar space. The Nasa mission, which launched from Earth in 1977, could leave our Solar System at any time.

Japan unfurls Ikaros solar sail in space

Japanese scientists are celebrating the successful deployment of their solar sail, Ikaros. The 200-sq-m (2,100-sq-ft) membrane is attached to a small disc-shaped spacecraft that was put in orbit last month by an H-IIA rocket.

Hawking backs interstellar travel project

Stephen Hawking is backing a project to send tiny spacecraft to another star system within a generation. They would travel trillions of miles; far further than any previous craft.

Dead stars 'to guide spacecraft'

Spacecraft could one day navigate through the cosmos using a particular type of dead star as a kind of GPS. German scientists are developing a technique that allows for very precise positioning anywhere in space by picking up X-ray signals frompulsars.

Complex organic molecule found in interstellar space

Scientists have found the beginnings of life-bearing chemistry at the centre of the galaxy. Iso-propyl cyanide has been detected in a star-forming cloud 27,000 light-years from Earth.

Centauri Dreams

I always keep an eye on the Phase I and Phase II studies in the pipeline at the NASA Innovative Advanced Concepts (NIAC) program. The goal is to support ideas in their early stages, with the 2022 awards going out to 17 different researchers to the tune of a combined $5.1 million.

Voyager near Solar System's edge

Voyager 1, the most distant spacecraft from Earth, has reached a new milestone in its quest to leave the Solar System. Now 17.4bn km (10.8bn miles) from home, the veteran probe has detected a distinct change in the flow of particles that surround it.

Former astronaut to lead starship effort

The Pentagon's premiere research agency has chosen a former astronaut to lead a foundation that is designed to take humanity to the stars. The Defense Advanced Research Projects Agency (Darpa) and Nasa are sponsoring the project, known as the 100-Year Starship.


It’s a dynamic star map that shows the closest star to you directly overhead when you look up. And since the Earth is constantly moving, our logo features different stars based on where you are and what time it is.

Move to new planet, says Hawking

The human race must move to a planet beyond our Solar System to protect the future of the species, physicist Professor Stephen Hawking has warned. He told the BBC that life could be wiped out by a nuclear disaster or an asteroid hitting the planet.

Will Wormholes Allow Fast Interstellar Travel?

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Elon Musk: Starship rocket close to going orbital

Elon Musk is hopeful he can launch his new monster rocket system in maybe a couple of months. In a presentation made while standing in front of what he calls the Starship, the US entrepreneur said the vehicle was close technically to being ready.

Breakthrough Initiatives

Breakthrough Initiatives is a science-based program founded in 2015 and funded by Julia and Yuri Milner,[1] also of Breakthrough Prize, to search for extraterrestrial intelligence over a span of at least 10 years. The program is divided into multiple projects.

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