This site uses cookies. By continuing to use this site you agree to our use of cookies. To find out more, see our Privacy and Cookies policy.
Skip to the content

Share this

Free weekly newswire

Sign up to receive all our latest news direct to your inbox.

Physics on film

100 Second Science Your scientific questions answered simply by specialists in less than 100 seconds.

Watch now

Bright Recruits

At all stages of your career – whether you're an undergraduate, graduate, researcher or industry professional – can help find the job for you.

Find your perfect job

Physics connect

Are you looking for a supplier? Physics Connect lists thousands of scientific companies, businesses, non-profit organizations, institutions and experts worldwide.

Start your search today


How common is life in the Milky Way?

By James Dacey

As Captain Kirk and his crew explore the Milky Way (and far, far beyond) they regularly encountering alien life. Often these life forms resemble humans, and frequently they have developed into civilizations far more advanced than those seen on Earth.

hands smll.jpg

Star Trek – I hate to break it to you – is a work of fiction. But while screenwriters have been sending the Starship Enterprise on its voyages to the final frontier, astronomers here on Earth have also been searching for alien worlds. They have been using telescopes to hunt for exoplanets and for signs that life could exist on them, such as whether these planets resemble Earth and whether they orbit within a habitable distance away from their parent stars.

Yesterday, astronomers announced a discovery that could give second-Earth-hunters a reason to be optimistic. Results from the European Southern Observatory’s High Accuracy Radial velocity Planet Searcher (HARPS) instrument revealed that our galaxy could be awash with rocky super-Earths orbiting within the habitable zones around faint red stars. The international team of researchers claims that there may be tens of billions of such planets in the Milky Way alone, and probably about 100 in the Sun’s immediate neighbourhood.

So is this a sign that life more than likely does exist in our galaxy? Or should we interpret this new finding the other way? Despite this abundance of potentially habitable planets, we are yet to be visited by one of our alien neighbours. Does this suggest that there is indeed something unique about the conditions on Earth beyond the composition of our planet and its proximity to the Sun? Even if life did emerge on one of our galactic neighbours, is it likely to have evolved into intelligent organisms?

We want to know your thoughts on this issue, via this week’s Physics World Facebook poll.

How common is life in the Milky Way?

We are alone in the galaxy
The galaxy is teeming with primitive organisms
We are by no means the most intelligent civilization in the galaxy

Have your say by casting your vote on our Facebook page. As always, please feel free to explain your response by posting a comment.

In last week’s poll we asked you a question relating to a more terrestrial issue: how to respond to climate change. Specifically, we asked whether you think it’s a good idea to engineer the climate to counter the effect of global warming? And the results are now in.

It seems that few respondents want to take a gung-ho approach, as only 14% opted for the “let’s do it!” option. The most popular choice – 49% of responses – is that “we should prepare to do it as a ‘plan B’ if carbon emissions continue to rise”. 24% of respondents opted for “No way! The environmental risks are too high”. Just 12% chose “No, because it won’t work anyway”.

Along with the votes, the poll also attracted some interesting comments on the issue. For instance, Joseph S Loveless, in Virginia, US, who opted for the preparing to use geoengineering as a plan B, said “Man meddling with nature rarely seems to have positive outcomes. That being said, since we are ‘engineering’ the climate as a by-product of reckless behaviour anyway, perhaps counter-engineering is the better argument than proposing we play God with the planet.”

Thank you for your participation and we look forward to hearing from you in this week’s poll.

This entry was posted in General. Bookmark the permalink.
View all posts by this author  | View this author's profile

Comments are closed.


  • Comments should be relevant to the article and not be used to promote your own work, products or services.
  • Please keep your comments brief (we recommend a maximum of 250 words).
  • We reserve the right to remove excessively long, inappropriate or offensive entries.

Show/hide formatting guidelines

Tag Description Example Output
<a> Hyperlink <a href="">google</a> google
<abbr> Abbreviation <abbr title="World Health Organisation" >WHO</abbr> WHO
<acronym> Acronym <acronym title="as soon as possible">ASAP</acronym> ASAP
<b> Bold <b>Some text</b> Some text
<blockquote> Quoted from another source <blockquote cite="">IOP</blockquote>
<cite> Cite <cite>Diagram 1</cite> Diagram 1
<del> Deleted text From this line<del datetime="2012-12-17"> this text was deleted</del> From this line this text was deleted
<em> Emphasized text In this line<em> this text was emphasised</em> In this line this text was emphasised
<i> Italic <i>Some text</i> Some text
<q> Quotation WWF goal is to build a future <q cite="">
where people live in harmony with nature and animals</q>
WWF goal is to build a future
where people live in harmony with nature and animals
<strike> Strike text <strike>Some text</strike> Some text
<strong> Stronger emphasis of text <strong>Some text</strong> Some text