Gliese 581d is the outlying planet in the Gliese 581 system, and orbits its parent star every 66.8 days. It may be covered by a large and deep ocean and is the first serious 'waterworld' candidate discovered beyond our Solar System.
Credit: ESO
"Stage fright! What do you say in an intergalactic message? Hello? Peace? What's the weather like? Know that we're here, we're waiting. Hear from you soon. Ally =]"
With these words Alexandra Lynch, a Brisbane schoolgirl, became the last person to contribute a goodwill message to the Hello From Earth website. At midday today, the messages were transmitted 20.3 light-years to the nearest Earth-like planet outside our Solar System, Gliese 581d.
A total of 25,880 messages were collected by the website, a COSMOS initiative to celebrate Australia's National Science Week and the International Year of Astronomy.
Done with the support of NASA, the CSIRO, and the Australia's Science Minister Kim Carr, it was a way of making people aware of our annual celebration of science, now in its 12th year, and get them thinking about the value and importance of science generally, and astronomy in particular.
And what an extraordinary success it has been: we had messages from Afghanistan to Alaska, from Morocco to Macau - in fact, from all 195 nations and even non-nations like Antarctica and Vatican City (not the Pope as far as we know).
More than 1,000 newspapers, in scores of languages, reported the initiative and than 9,917 blogs around the world discussed it and linked to the site; there were thousands of tweets in French, Russian, Indonesian and any other language you can image.
Visitors to the site reached 254,620 in the 13 days the site collected messages, and visitors read 1.25 million pages; from the various messages left by participants to articles on exoplanets and astrobiology.
Some of the messages included:
Yidumduma Bill Harney, an Aboriginal astronomer of the Wardaman people: "Yidigunmardin nuruku yajingewa wuremulu jandange. Our dream, we're telling to them young kids. We're talking all this dream for the future."
Patty, Melbourne: "What I've learnt: believe in yourself, believe in others, keep confidences, that family matters, you get what you give, dare to dream and don't forget to laugh."
Fred Mason, Roberts Creek: "Hi there: Sorry about The Outer Limits; hope you enjoyed I Love Lucy. Have you got all our missing socks? Love, Earth."
Class4M, Castle Cove Public School, Australia:We come in peace. If you are out there, please respond. We want to be friends. We are all different and we can't wait to meet you! From the children of Earth.
On Friday 28 August 2009, at midday, the Canberra Deep Space Communication Complex at Tidbinbilla transmited the messages, encoded into binary. They were sent at a frequency of 7.145 gigahertz and a power of 18 kilowatts, in the direction of Gliese 581d, an exoplanet only recently discovered to be in its star's habitable zone.
Gain from the antenna transmission source will increase this greatly: the signal is equivalent to using the combined transmission power of 300 billion mobile phones. NASA engineers will aim at azimuth 87 degrees at an elevation of 17 degrees at the start of transmission - the location of Gliese 581 will be when the message arrives around December 2029 - and the signal will be repeated twice over two hours.
Will we get a response? It's unlikely - while a modern review of the Drake Equation suggests the number of detectable civilisations may be 200 in our galaxy alone, the universe is so vast that it is unlikely this particular star system is inhabited - much less harbours intelligent life with advanced technology.
But it's been an interesting exercise in seeing just what people would say to extraterrestrials, given the chance.
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THAT was a GREAT GAME!
global. geeky. genious. and great!
thanks for your imagination, initiative, organising and hard work.
(please start another game soon!)
Robyn
Adelaide, Australia
Does Intelligent Life Exist Elsewhere...?
For me, the strongest undoubted evidence, that intelligent life actually exists elsewhere in the universe, is the fact, that so far, none of them, have tried to contact US.....!
Miles-traveled-so-far counter
Hello all! How about adding a counter on the Hello From Earth page that shows us how many miles (and kilometers) our message has traveled?
what-do-ya-say?
Richard
The message is averaging 16 billion miles a day. I did the math. :)
(It should now be 64 billion miles from Earth)
Distance counter - cool
I calculated 25,902,068,371.2 km a day (or 25.9 billion km). That's cool.
The idea of adding a counter for how many kilometers (and miles) the message has traveled is a really cool idea.
At this rate, the messages will cross the heliopause on Nov 21 this year, and reach the Oort cloud on 25 Jan 2010.
Thanks for the idea!
Wilson da Silva
Editor, COSMOS
Subscription refund...?
I give up.........!
Can I get a refund on my subscription please.....???
Better idea
How about a countdown timer for arrival of the message at it's destination and for earliest arrival of a return message? I bet if anyone were there, the easiest way to show they're there is to send back our message verbatim and then tack on their own reply. That's what I'd do anyway, and that's basically what we do when replying to e-mail, although in reverse order.
Of course, if we were to receive a message from space, it would probably take some time to decipher and then some discussion about whether a response is appropriate at all, and if so, what response. I expect no less of any other sentient being.
Since we're talking a little over 20 years away, if our TV and radio signals are strong enough to detect there, they're now watching shows like Star Trek and Battlestar Galactica instead of I Love Lucy, and wondering about our motives in contacting them, or perhaps when we'll arrive there with the cylons or klingons hot on our tails, wreaking death and destruction wherever they go! In fact, they'd have had a good generation or more to respond to us by now.
What was the calculation of signal to noise ratio at 20 light years distance? I've got my doubts they'd even notice. With our best technology, so far we've only managed to maintain telemetry with the space probes for less than two thousandths of a light year, just a blink of an eye, compared to 20LY. However, the land-based signals can at least be much stronger. But then again, they also have to get through the atmosphere and magnetosphere of Earth, which considerably weakens them. Try sending from a high-power lunar based repeater.
Miles counter is there ......
http://www.hellofromearth.net/gliese581d/whatis/index.htm
Refer this Website for knowing how much our message has travelled.
Yours in touch,
N.M.BALAJI
Message Mileage...
The Hello From Earth message is averaging 16 billion miles a day. I did the math :)
It should now be 64 billion miles from Earth as of this comment.