Stephen Hawking (University of Cambridge Professor) – Why We Should Go Into Space | NASA’s 50th Anniversary lecture series (Apr 2011)

Chapters

Abstract

The Future of Humanity: A Journey Beyond Earth

In an age where the infinite cosmos beckons, Stephen Hawking’s vision of space exploration emerges as a roadmap for humanity’s long-term survival and advancement. Drawing parallels with Columbus’s voyage, Hawking envisions a future where space exploration greatly impacts humanity, extending beyond our planet to ensure our species’ continuity. This exploration is not just about reaching new celestial bodies; it’s about fostering unity, inspiring scientific curiosity, and confronting existential risks. With a proposed timeline stretching centuries and targets like lunar bases, Mars colonization, and even interstellar travel, Hawking’s plan is a clarion call for a strategic, sustained journey into the unknown.

Justification for Space Exploration

Hawking’s argument for space exploration transcends mere scientific curiosity. He sees it as a necessity for human survival, much like Columbus’s voyage was for expanding human horizons. Space exploration offers a fresh perspective on Earth’s challenges, promoting global unity and a shift from inward to outward focus. This grand venture is envisioned over hundreds or thousands of years, with achievable milestones such as establishing a lunar base in 30 years and reaching Mars in 50 years, culminating in the exploration of outer planet moons in two centuries. While these endeavors may seem expensive, Hawking emphasizes that the proportion of global resources needed is relatively small.

Historical Comparison

Hawking draws a parallel between the current skepticism towards space exploration and the resistance Christopher Columbus faced before his voyage to the Americas. He emphasizes the profound impact that the discovery of the New World had on the old, citing examples like the Big Mac and KFC as evidence of its global influence. Hawking believes that space exploration will have an even greater impact, potentially determining the future of humanity and expanding our perspective beyond Earth.

Funding and Balancing Earth’s Priorities

Despite the historical achievements like the Apollo landings, NASA’s budget has stagnated since the 1970s. Hawking underscores that a significant increase in the international space budget would still constitute a minor fraction of global GDP. He acknowledges the importance of solving pressing Earthly issues like climate change and pollution but advocates that a balanced approach can accommodate space exploration without compromising our planet’s welfare.

Public Engagement and Human Spaceflight

Hawking stresses the significance of manned space missions for their inspirational value. While robotic missions yield scientific data, they lack the charisma to engage the public and drive human expansion into space. He suggests ambitious goals like a lunar base by 2020 and a manned Mars landing by 2025 to rekindle public enthusiasm and restore a sense of purpose in space exploration, akin to President Kennedy’s moon landing target in the 1960s.

The Importance of Science and the Search for Extraterrestrial Life

Hawking laments the waning interest in science among young people, viewing space exploration as a beacon to elevate science’s status and inspire future scientists. His belief in the possibility of extraterrestrial life arises from the sheer number of planets in the galaxy, suggesting that life could have arisen spontaneously on suitable planets. He posits that, given the universe’s vastness, life is likely to have emerged elsewhere, though the probability of contact remains slim.

Detection of Extrasolar Planets

Observations suggest that a substantial number of stars have planets orbiting them. Current technology can only detect giant planets comparable to Jupiter and Saturn.

The Possibility of Earth-Like Planets

It is reasonable to assume that smaller, Earth-like planets accompany the detected giant planets. Some of these planets may reside in the Goldilocks zone, where conditions allow for liquid water to exist on their surface.

Potential Earth-Like Worlds Nearby

Within a 30-light-year radius of Earth, approximately 1,000 stars exist. Assuming 1% of these stars have Earth-sized planets in the Goldilocks zone, there are potentially 10 candidate new worlds.

Challenges and Long-Term Goals

Visiting these potential Earth-like planets is currently beyond our technological capabilities. Interstellar travel should be considered a long-term objective, aiming for the next 200 to 500 years.

Panspermia and the Origin of Life

The theory of panspermia, suggesting life can spread across planets or star systems via meteors, offers an intriguing explanation for life’s origins on Earth. The rapid emergence of life on our planet, within 500 million years of its formation, supports either panspermia or a high probability of independent life formation.

Challenges and Sites for Human Colonization

Space travel and colonization face physiological challenges, as evidenced by experiences from the International Space Station. Potential colonization sites like the Moon and Mars present their unique challenges and opportunities. The Moon, with its proximity and relative ease of access, and Mars, with its past potential for life and existing resources, are prime candidates for human colonization.

The Infinite Journey

Stephen Hawking’s vision paints a future where humanity’s destiny is intertwined with the cosmos. The search for extraterrestrial life and potential human colonization beyond Earth are not mere scientific endeavors; they represent a crucial step for humanity’s continued existence and evolution. While our current technology falls short for interstellar travel, the pursuit of such a goal over the next 200 to 500 years symbolizes our species’ unyielding spirit of exploration and survival. This journey, stretching from our nearest celestial neighbors to the distant stars, is a testament to humanity’s relentless quest for knowledge and a future beyond our blue planet.

The Importance of Exploration

The human race has existed as a distinct species for around 2 million years. Civilization emerged approximately 10,000 years ago, and the pace of development has been accelerating. If humanity is to survive for another million years, bold steps into the unknown, such as interstellar exploration, are necessary.

Notes by: Random Access