Are We Alone? Life in the Universe

Advanced Aliens: Why ET Will Be More Advanced than Humanity

Seth Shostak, Senior Astronomer, SETI

Any beings capable of bridging the vast distances between the stars would be able to clean our clock when it comes to science and engineering. Visitors from other worlds – should any appear – would be enormously ahead of us from a technological viewpoint. It may surprise you to learn that the same is true for any aliens we might tune in with our SETI experiments.  R

Advances in our Understanding of Life

Jack D. Farmer, NASA, 2001

Over the past two decades, advances in a number of scientific disciplines have helped us better understand the nature and evolution of life on Earth. These scientific developments also have helped lay the foundation for astrobiology, opening up new possibilities for the existence of life in the Solar System and beyond. R

Alien Intelligence? Think Again

Guillermo Gonzalez, Space.com, 29 February 2000

Skeptical article on ET intelligence. "The existence of extraterrestrial intelligence (ETI) has been debated since the ancient Greeks. Over the last few decades, both intellectual and public opinion have been decisively in the pro-ETI camp. Unfortunately, the debate has taken place on a very slanted playing field, at least in the United States." R

Alien life: Would we recognize it at all?

Seattle Times, January 8, 2003

Hundreds of astronomers yesterday learned that life in outer space is likely to lack green eyes and be far more prosaic, tiny and, quite possibly, completely unlike life as we know it. This blunt appraisal came from the University of Washington's Center for Astrobiology and Early Evolution, one of the first programs in the country to give an advanced degree in astrobiology.  R

Alien Life? Astronomers Predict Contact by 2025

Hillary Mayell, National Geographic News, November 14, 2003

Earthlings could make contact with extraterrestrial beings by the year 2025, two astronomers predict in a new book. The authors say it's unlikely space aliens look like Hollywood's ET—little, green, and hairless—and that while aliens are highly unlikely to pay Earth a visit, they may be sending radio signals across space to let us know they exist. R

Are We Alone? Where are our Nearest Neighbors?

Edward Weiler, NASA Astrobiology Institute, August 6, 2001

Edward Weiler, NASA's Associate Administrator for Space Science discusses the search for life in the Universe. Are we alone? R

Defining Life

By Leslie Mullen, Astrobiology Magazine, Jun 19, 2002

What is life, exactly? This is a question that keeps biologists up at night. The science of biology is the study of life, yet scientists can't agree on an absolute definition. What about a computer program that learns and evolves? Can a wild fire - which feeds, grows, and reproduces - be considered a living entity? R

Drake Equation Naeye Sayer

Terence Dickinson, The Sunday Toronto Star, Dec. 7, 2003

In 1961, American astronomer Frank Drake developed his famous equation for estimating the number of technologically advanced civilizations in the galaxy. However, more and more scientists are having their doubts about the optimistic numbers and a substantial number of researchers consider the equation as obsolete as a black and white television from the '60s.  R

Exotic Earths

David Lamb, NASA Astrobiology Institute

New astronomical techniques are vastly increasing what we know about extrasolar planets. Scientists have already found a large number of Jupiter sized bodies, but what about Earth-like planets in other solar systems? R

Galactic Habitable Zones

Leslie Mullen, Science Communications, NASA Astrobiology Institute, May 18, 2001

Our Milky Way Galaxy is unusual in that it is one of the most massive galaxies in the nearby universe. Our Solar System also seems to have qualities that make it rather unique. According to Guillermo Gonzalez, Assistant Professor of Astronomy at the University of Washington, these qualities make the Sun one of the few stars in the Galaxy capable of supporting complex life. R

How Far is ET?

Seth Shostak, Special to Space.com

How many light-years is it to the nearest alien civilization? In 1960, when Frank Drake made the first modern effort to eavesdrop on radio signals from ET, he trained his antenna on two relatively close stars, Epsilon Eridani and Tau Ceti: respectively 10 and 12 light-years from Earth. He picked these backyard buddies for several reasons.  R

Pros and Cons of Life Existing Elsewhere

Dennis Balthaser, 07/01/00

I recently wrote an editorial entitled "Are We Alone?" and decided maybe I should follow it up with a similar editorial, since the question of life elsewhere in our universe continues to plague us. For honesty purposes, this editorial will probably be somewhat biased, because as a UFO researcher, I think the possibilities are overwhelming in favor of life elsewhere. In fairness, I will try (using others thoughts), to give a "for" and "against" view on the subject. R

Rare Earth Debate Part 1: The Hostile Universe

Space.com, July 2002

When the book "Rare Earth" was published two years ago, it raised a great deal of controversy among astrobiologists. Written by Peter Ward and Donald Brownlee, the book's hypothesis suggests complex life is rare in the universe, and may even be unique to Earth. This debate, a 5-part series, will cover a variety of topics prompted by the Rare Earth hypothesis.  R

Rare Earth Debate Part 2: Alien Proximity

Space.com, July 2002

This five-part debate will cover a variety of topics prompted by the hypothesis of "Rare Earth," a book by Peter Ward and Donald Brownlee that suggests complex life may be unique to Earth. The focus on microbial life continues today in Part 2 as the moderator asks where we can expect to find life in our solar system and beyond.  R

Rare Earth Debate Part 3: Complex Life

Space.com, July 2002

This five-part debate will cover a variety of topics prompted by the hypothesis of "Rare Earth," a book by Peter Ward and Donald Brownlee that suggests complex life may be unique to Earth. Today the participants examine complex life and the possibility of its occurrence in the universe. Complex life is generally considered any living thing with multiple cells -- as opposed to single celled, microbial life -- and, on Earth anyway, includes everything from the simplest slime molds to human beings.  R

Rare Earth Debate Part 5: Elusive ET

Space.com, July 2002

This five-part debate has covered a variety of topics prompted by the hypothesis of "Rare Earth," a book by Peter Ward and Donald Brownlee that suggests complex life may be unique to Earth. Today in the final installment the participants examine why we haven’t found complex intelligent life, if indeed it does exist elsewhere in the universe. A thread of this debate also picks up on a comment made by Donald Brownlee in Part 4 -- that interstellar space travel may be impossible.  R

Signs of Life: On the Lookout for Extraterrestrial Sweet Spots

Leonard David, SPACE.com, 03 January 2002

Looking for life elsewhere is a tough task for human or robot. The good news is that the scientific skill and tools to search for, detect and inspect extraterrestrial life are advancing rapidly. R

Skepticism With Wonder

Carol Oliver, Australian Centre for Astrobiology, interview in Astrobiology Magazine

The challenge to communicate both the breadth and depth of astrobiology is discussed by Carol Oliver, of the Australian Centre for Astrobiology. As a researcher in communicating science, she considers how best to tell a busy public what it means to explore other worlds for signs of life elsewhere. R

The Galactic Civilizations: Part V

Astrobiology Magazine

This is the fifth and final part of a series of presentations given at a public forum sponsored by the NASA exobiology branch. The forum, held in Palo Alto, CA, on Tuesday, August 26, 2003, was entitled, "The Drake Equation Revisited." This installment addresses the evolution of machine intelligence and the potential for civilizations that span the galaxy. R

The Meaning of Life

Lee Siegel, NASA Astrobiology Institute, July 6, 2001

Sitting beneath a dark night sky, looking up at the vast array of stars, what human has not wondered, "Are we alone?" R

The Search for Life in the Universe

Neil deGrasse Tyson, to the House Subcommitee on Space and Aeronautics

Neil deGrasse Tyson discusses the search for life in the Universe. Are we alone? R

The Unexplored Cosmos

Ann Druyan and Steven Soter, interview in Astrobiology Magazine

Cosmos collaborators, Ann Druyan (widow of Carl Sagan) and astrophysicist Steven Soter, talk about the possiblities for finding life elsewhere and the implications for understanding humanity's own place in the universe. R

Time Enough for Life

Peter Backus, SETI Institute, on Space.com, 16 October 2003

In our hectic world, we seldom have time enough for life: time for family, time for friends, or time for the pleasures of life. In studying the universe, Astrobiologists face a different problem: which stars might provide time enough for life? The answer depends on the life of the star. R

Astrobiology Magazine: Search for Life in the Universe

NASA Astrobiology Institute

Astrobiology is devoted to the scientific study of life in the universe - its origin, evolution, distribution, and future. In 1998 NASA established the NASA Astrobiology Institute (NAI) as one element of its research program in astrobiology.

NASA Astrobiology Institute - Features Archive