Full title: “On the Origin of Species By Means of Natural Selection, or, the Preservation of Favoured Races in the Struggle for Life” by Charles Darwin.

We were discussing this book on the #PopSciBookClub forum and I thought I’d write a quick post about it.

It is a book that everyone has heard of, but not everyone has read. My recommendation? Read it!

Charles Darwin

Charles Darwin (Image: Wikimedia Commons)

Considering it was published in 1869, it’s surprisingly readable. I recommend you read it if you haven’t.  You can get it free on Amazon Kindle.

The first few chapters are brilliant and I’d recommend everyone read these, if nothing else. I really enjoyed seeing all the famous quotes in context, including the ones quote-mined by creationists!

After the first few chapters he goes into all the evidence that he has gradually gathered to justify his statements made in the first few chapters. I think that you could potentially skip most of these. Obviously, at the time of publication, he had to “show all his working” – I skimmed through most of this; I didn’t feel I needed to see his evidence . It’s a bit like if you pick up a scientific paper: you can just read the abstract, introduction and conclusion – and you only need to go into method and results if you don’t believe the author.

I highlighted loads of text while I was reading. If you don’t want to read the book, you can at least read these beautiful passages!

On species being independently created:

Although much remains obscure, and will long remain obscure, I can entertain no doubt, after the most deliberate study and dispassionate judgment of which I am capable, that the view which most naturalists entertain, and which I formerly entertained–namely, that each species has been independently created–is erroneous. I am fully convinced that species are not immutable; but that those belonging to what are called the same genera are lineal descendants of some other and generally extinct species, in the same manner as the acknowledged varieties of any one species are the descendants of that species. Furthermore, I am convinced that Natural Selection has been the main but not exclusive means of modification.

On selective breeding:

The key is man’s power of accumulative selection: nature gives successive variations; man adds them up in certain directions useful to him. In this sense he may be said to make for himself useful breeds.

Introducing the term “Natural Selection”:

…two countries very differently circumstanced, individuals of the same species, having slightly different constitutions or structure, would often succeed better in the one country than in the other, and thus by a process of “natural selection,” as will hereafter be more fully explained, two sub-breeds might be formed.

On variation and the struggle for life:

Owing to this struggle for life, any variation, however slight and from whatever cause proceeding, if it be in any degree profitable to an individual of any species, in its infinitely complex relations to other organic beings and to external nature, will tend to the preservation of that individual, and will generally be inherited by its offspring.

Natural Selection:

I have called this principle, by which each slight variation, if useful, is preserved, by the term of Natural Selection, in order to mark its relation to man’s power of selection.

But Natural Selection, as we shall hereafter see, is a power incessantly ready for action, and is as immeasurably superior to man’s feeble efforts, as the works of Nature are to those of Art.

Natural selection can act only by the preservation and accumulation of infinitesimally small inherited modifications, each profitable to the preserved being; and as modern geology has almost banished such views as the excavation of a great valley by a single diluvial wave, so will natural selection, if it be a true principle, banish the belief of the continued creation of new organic beings, or of any great and sudden modification in their structure.

Darwin didn’t understand the cause of variation:

Whatever the cause may be of each slight difference in the offspring from their parents–and a cause for each must exist–it is the steady accumulation, through natural selection, of such differences, when beneficial to the individual, that gives rise to all the more important modifications of structure, by which the innumerable beings on the face of this earth are enabled to struggle with each other, and the best adapted to survive.

On the incomplete fossil record:

Whilst the bed of the sea is stationary or is rising, or when very little sediment is being deposited, there will be blanks in our geological history. The crust of the earth is a vast museum; but the natural collections have been made only at intervals of time immensely remote.

The eye:

To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree. Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real. How a nerve comes to be sensitive to light, hardly concerns us more than how life itself first originated; but I may remark that several facts make me suspect that any sensitive nerve may be rendered sensitive to light, and likewise to those coarser vibrations of the air which produce sound.

Slight successive variations:

Why should all the parts and organs of many independent beings, each supposed to have been separately created for its proper place in nature, be so invariably linked together by graduated steps? Why should not Nature have taken a leap from structure to structure? On the theory of natural selection, we can clearly understand why she should not; for natural selection can act only by taking advantage of slight successive variations; she can never take a leap, but must advance by the shortest and slowest steps.

Related posts

PopSciBookClub: All the posts.

Posted by: Kash Farooq | August 6, 2013

I’m going to defend Michael Gove. Well, sort of.

Michael Gove - Secretary of State for Education. Image: Wikimedia Commons

Michael Gove – Secretary of State for Education. Image: Wikimedia Commons.

Let me start by stating that I’m not a fan of Michael Gove. I really really really am not a fan. I cannot stress how much I am not a fan.

He seems to be intent on returning education methods and assessment to how it was when he was a lad. This apparently also includes making everyone read the books that he had to read. And learn about Kings and Queens like he had to. At least, that’s the impression I get.

He appears to be ignoring all education research and progress from, say, the last 40 years and instead is trying to bring back the good old single exam assessment at the end of the year. Forget this continuous assessment nonsense! A child’s future needs to depend on how they perform during that two-three week exam period and not on something they worked on 6 months ago!

Rant over. I’m not going to go into any further details of Gove’s ideas. You can listen to the accidental Michael Gove special for a full recap: Pod Delusion episode 187.

So, how on Earth am I going to defend him? And what about?!

Well, I’d like to defend his ability to back down. His increasingly frequent “U-turns”.

Do a search for “Michael Gove U-turn” and these are some of the headlines you’ll see:

And it’s not just the papers that jump on these changes of plan. The opposition inevitably jump in too. Back in February the Shadow education secretary, Stephen Twigg, called Michael Gove’s GCSE U-turn a “humiliating climbdown”.

So what’s the problem?

Let’s think about the alternative. Gove ignores everyone’s advice, everyone’s howls of protest and bulldozes his reforms through anyway. That would be more to worry about wouldn’t it? The U-turn is a good thing isn’t it?

Basically, we need to remove the negativity surrounding the phrase “U-turn”.

I’m not proposing anything new here. I first heard about viewing U-turns as something positive in Mark Henderson‘s “Geek Manifesto“, a book I highly recommend. Quoting from the book:

We should praise honest failure accomplished by applying the scientific method to public policy and encourage U-turns made in the face of the evidence.

And there is also an excellent idea by the economist and journalist Tim Harford: there should be an annual award given to the politician who has been most usefully wrong and admitted to it.

Granted, Michael Gove may not have used evidence, or the scientific method, to change his mind. Perhaps he realised just how unpopular his ideas were. Or perhaps he listened to some advice from a civil servant. Whatever motivated him, I’d prefer that he did change his mind rather than him simply ignoring everyone and carrying on with his ridiculous idea of the month.

So, let’s all look forward to the next Gove U-turn! No doubt there will be one and we will all be very glad that something has managed to change his mind again and that he did abandon a proposed reform.

Related Articles


 


I recorded this for Episode 198 of The Pod Delusion – a podcast about interesting things.

Posted by: Kash Farooq | August 4, 2013

The Pod Delusion Interviews – 2011

The Pod Delusion Logo

[What is this about? See The Pod Delusion Interviews]

Episode 104, 30th September 2011: Faster than light neutrinos

Interviewee: Dr Ben Still, neutrino physicist.

Remember when the Gran Sasso lab in Italy thought the neutrinos they were being sent by CERN were arriving too quickly? Neutrinos were arriving faster than should be possible according to Einstein’s Theory of Special Relativity. Luckily, for my first ever interview, I knew the perfect person to talk to about the physics news that had become front page news: neutrino scientist and excellent science communicator, Ben Still.

Links:

Episode 106, 14th October 2011: It IS Rocket Science 

Helen Keen - It IS Rocket Science

Helen Keen – It IS Rocket Science

Interviewee: Helen Keen, comedian and creator of the stage and BBC4 radio show It IS Rocket Science.

We caught up with Helen at the British Library to discuss her work and her latest science-themed comedy show.

Links:

Episode 107, 21st October 2011: The 2011 Nobel Prize in Physics

Interviewee: Professor Brian Schmidt, astrophysicist and 2011 Nobel Prize in Physics Joint Winner

The Pod Delusion - Brian Schmidt (Photo credit - Belinda Pratten


The Pod Delusion – Brian Schmidt (Photo credit – Belinda Pratten)

No, I’m still not sure how this happened. A few days after Brian had been awarded the Nobel Prize, I (extremely optimistically) sent an email to him asking for an interview. I nearly fell off my chair when the next day I received an email from the Australian National University press department, who wanted to get it scheduled.

Links:

Episode 111, 18th November 2011: The Russian Phobos-Grunt launch failure

Interviewee: Dr Lewis Dartnell, astrobiologist and author.

Life in the Universe, by Lewis Dartnell

Life in the Universe, by Lewis Dartnell

A discussion about what happened to the recently launched Russian spacecraft and why astrobiologist Lewis Dartnell was so interested in this mission.

Links:

Episode 112, 25th November 2011: Mars Curiosity Rover

Interviewee: Dr Claire Cousins, planetary scientist.

A discussion about the Mars Science Lab/Mars Curiosity Rover just before it was launched.

Links:

Episode 113, 2nd December 2011: The Venus Transit Expedition 2012

Interviewee: Huw James, Scientist, Presenter, Adventure Junkie.

We discuss Huw’s plans to organise an expedition to travel across Europe and Asia by land to view the Venus Transit.

Links:

Episode 114, 9th December 2011: Kepler-22b and the search for Earth 2.0

Interviewee: Dr Robert Simpson, astrophysicist and web developer.

After yet another “We have found Earth 2.0” announcement, I put out a tweet “are there are any pissed off astronomers who want to be interviewed about the latest Earth 2.0”. Rob answered my call!

Links:

Episode 115, 16th December 2011: Higgs Update

Interviewee: Professor Jon Butterworth, physicist at UCL and CERN.

I’ve known Jon on Twitter for a while, and after the first announcement that the LHC may have spotted the Higgs Boson, I called him to discuss what they’d found.

Links:

Posted by: Kash Farooq | July 15, 2013

Space Scenery: Enceladus

The Cassini spacecraft, which is currently orbiting around Saturn, has given us many stunning images. And it has made some stunning discoveries.

One such discovery is that plumes of water ice are venting from one of Saturn’s small moons, Enceladus:

Plumes of ice venting from Enceladus.

Plumes of ice venting from Enceladus.

This was a complete surprise. Enceladus was thought to be too small to be geologically active.

Since the initial discovery, there have since been several close encounters. Indeed, Cassini has flown through the plumes and various molecules have been detected, including water and even organic chemicals.

Plumes of icy particles venting from Enceladus.

Plumes of icy particles, water vapour and organic compounds spray out from the tiger stripes near the south pole of Saturn’s moon Enceladus.

Before we get to some detailed images of the surface and the vents, let’s first take a look at some eye candy:

The ice-covered moon, Enceladus.

The ice-covered moon, Enceladus.

Enceladus, Saturn's rings and Titan.

Enceladus, Saturn’s rings and Titan in the distance.

Enceladus backdropped by ring shadows on Saturn.

Enceladus backdropped by ring shadows on Saturn.

Enceladus in front of Saturn's Rings and rings' shadows.

Enceladus in front of Saturn’s Rings and rings’ shadows.

Now for some bigger, more details images:

The North Polar Region of Enceladus

This is a three-image mosaic and is one of the highest resolution images of Enceladus’ north polar region. Click for 3380 x 2211 version.

And in this image you can see the “tiger stripes” – these are where the ice plumes vent from (click for 3237 x 3812 version):

Fresh tiger stripes on Enceladus

A high resolution Cassini image of Enceladus from a close flyby showing newly created ‘tiger stripes’ – shown here in false-colour blue. The so-called tiger stripes are known to vent ice from the moon’s interior and actually create and sustain one of Saturn’s rings – the E-ring. Click for 3237 x 3812 version.

Enceladus Trailing Hemisphere

This image was created from 16-images and shows the “trailing hemisphere” – the side of Enceladus that always faces away from the direction of the satellite’s orbital motion around Saturn. Click for 8804 x 8804 version.

Enceladus Mosaic

This image was created from four high resolution images taken by the Cassini spacecraft narrow angle camera. The view is about 300 kilometres across and shows the faults, fractures, folds, troughs and craters. Click for 3750 x 2876 version.

Close-up of the south polar terrain and the tiger stripe fractures.

Close-up of the south polar terrain and the tiger stripe fractures. Click for 5500 x 7700 version.

A flattened map of the surface (click for the 7200 x 3600 version):

This mosaic shows a global map of Enceladus.

This mosaic shows a global map of Enceladus.

Related Posts

Space Scenery series.

Posted by: Kash Farooq | June 25, 2013

The Pop Sci Book Club – Book 3

Psocoptera - an order of insects that are commonly known as booklice.

Psocoptera – an order of insects that are commonly known as booklice.

[If you are unsure what this is all about, see The Pop Sci Book Club -  an introduction]

Our third book has been selected by Peter Harrison: we are going to read Stephen Jay Gould’s Wonderful Life: Burgess Shale and the Nature of History (352 pages).

So, please buy the book and join the Pop Sci Book Club forum.

The book specific forum for this book: Wonderful Life: The Burgess Shale and the Nature of History (Stephen Jay Gould).

Wonderful Life - Burgess Shale and the Nature of History - by Stephen Jay Gould

Related posts

Posted by: Kash Farooq | May 19, 2013

Carl Sagan and the Pioneer Plaques

The Pioneer 10 and Pioneer 11 launched March 2, 1972 and April 5, 1973 respectively:

An artist's view of a Pioneer spacecraft heading into interstellar space

An artist’s view of a Pioneer spacecraft heading into interstellar space. Both Pioneer 10 and 11 will eventually exit the Solar System. Pioneer 11 sent its last signal in November 1995, while Pioneer 10 lasted until January 2003. Image credit: NASA Ames Research Center

Each spacecraft carried identical plaques:

The Pioneer plaques.

The Pioneer plaques were placed on board the Pioneer 10 and Pioneer 11 spacecraft – there is a lot of information in this picture.

NASA gave Carl Sagan permission to send a message with the Pioneer spacecraft, so that if the spacecraft were to be intercepted by extraterrestrial life they could learn something about the human race. Together with Frank Drake the plaque designed. Sagan’s wife at the time, Linda Salzman Sagan, did the artwork.

They wanted to tell ET where we were, what we looked like, how tall we were, etc. But how do you tell ET something about you when you haven’t got much in common? They won’t have any common units of measurement. They won’t know how a long a second lasts or how long one metre is.

Well, we both live in the Universe for starters. We can use universal measurements. This is where the two circles in the top left hand corner of the plaque represent. They depict hydrogen (the most common element in the Universe) and a certain electron energy transition. This transition produces an important spectral line in astronomy: the “21 cm hydrogen spectral line“. As the name suggests, the line corresponds to a wavelength of 21 cm and it also represents a frequency of 1420 MHz (which is a unit of time).

[For more information, I've written a few blog posts about the fascinating subject of spectroscopy. We can learn a lot about distant objects using spectroscopy]

Now we have communicated some information about length, we can discuss the pictures of the humans. The dots to the right of the female represent in binary 1000, which is 8. 8 x 21 cm = 168 cm: giving a height of a typical human. Incidentally, Sagan originally wanted the man and woman to be holding hands but then thought that ET would think the picture represented a single creature with two heads!

Moving onto the radial star-like pattern. This is where the information about time is used:

Pioneer Plaque - "We Are Here" Pulsar Map

Pioneer Plaque – “We Are Here” Pulsar Map

This part of the picture (which was also etched onto the Voyager Golden Record) is a “we are here” map. There are 15 lines in this diagram, with 14 representing pulsars. Pulsars are a type of dead star – they are rapidly rotating neutron stars and were first discovered in 1967 by Jocelyn Bell Burnell. “Jets” of radio radiation are emitted from the magnetic poles of the star. Each time a pole points at Earth, we see a pulse of radio waves. We see some pulsars emit radiation at incredibly regular intervals – so regular they can be used for precision timing. The frequency of the pulses can also be very rapid – the fastest-spinning pulsar currently known spins at about 716 times a second!

Given how bright and useful pulsars are, pulsars are used to show where we are. The lengths of the lines show the relative distances of the pulsars to the Sun. A tick mark at the end of each line shows how far the pulsar is from the plane of the Milky Way. The “notches” on each line are binary numbers giving the frequency of pulses in the units provided by the 21 cm hydrogen line. The non-pulsar line (it extends from the centre of the radial map to behind the human figures) indicates the Sun’s relative distance to the centre of the galaxy.

The bottom of the plaque shows the Solar System with the large Sun on the left:

Diagram of the Solar System

Diagram of the Solar System, with the trajectory of the Pioneer spacecraft shown.

The sizes of the planets are to scale, but obviously the distances are not. The notches above/below each planet represent in binary the relative distance to the Sun.

Notice the arrow showing the trajectory of the Pioneer spacecraft. An article in Scientific American criticized the use of an arrow as ET may find the arrow symbol meaningless. Also, though Pioneer took the shown trajectory (via Jupiter), Pioneer 11 actually exited the plane of the Solar System via Saturn.

Also notice there are 9 planets: Pluto was still classed as a planet back then!

Images from Wikimedia Commons

Posted by: Kash Farooq | April 30, 2013

The Pop Sci Book Club – Book 2

Psocoptera - an order of insects that are commonly known as booklice.

Psocoptera – an order of insects that are commonly known as booklice.

[If you are unsure what this is all about, see The Pop Sci Book Club -  an introduction]

For our second book (as selected by Chrissy), we are going to read Richard Feynman’s Six Easy Pieces: Fundamentals of Physics Explained (176 pages). It’s a perfect choice as it’s Feynman’s birthday on 11th May!

So, please buy the book and join the Pop Sci Book Club forum. I’ll create the book specific discussion forum around 11th May 2013.

Update: I’ve now created the forum to discuss the book.

Six Easy Pieces - Fundamentals of Physics Explained - by Richard Feynman

Related posts

Posted by: Kash Farooq | April 21, 2013

Space Scenery: The Space Shuttle Programme

Officially named “Space Transportation System” (STS), we all know it as the Space Shuttle – an iconic, incredibly photogenic spacecraft. It started operations 1981 (1981!) and retired recently – in 2011.

It is the only reusable space vehicle that has ever made multiple flights into orbit (though it was criticised for being a very expensive way to get to space and back).

And, of course, it had two fatal accidents. Challenger (STS-51-L) exploded 73 seconds after launch on January 28, 1986; Columbia (STS-107) disintegrated on its return trip on February 1, 2003. Space travel is dangerous.

On to the pictures. There are so many to choose from. As I’ve already said – the Space Shuttle is an incredibly photogenic spacecraft. And together with the surroundings it operated in, there are so many stunning images out there.

So, here are a few that I’ve been gradually collecting for the Space Scenery series.

As always, click the image to see a much higher resolution image.

Ground

Space Shuttle Atlantis waiting for launch day.

Space Shuttle Atlantis waiting for launch day.

With a rainbow as a backdrop, Space Shuttle Atlantis in the foreground sits on Launch Pad A; Endeavour at Launch Pad B (NASA’s Kennedy Space Center in Florida, image credit NASA/Troy Cryder).

With a rainbow as a backdrop, Space Shuttle Atlantis in the foreground sits on Launch Pad A; Endeavour at Launch Pad B (NASA’s Kennedy Space Center in Florida.

NASA's space shuttles Endeavour and Atlantis switched locations at Kennedy Space Center in Florida, and in the process came "nose-to-nose" for the last time in front of Orbiter Processing Facility 3. (Image credit: NASA).

NASA’s space shuttles Endeavour and Atlantis switched locations at Kennedy Space Center in Florida, and in the process came “nose-to-nose” for the last time in front of Orbiter Processing Facility 3.

Launch

Space Shuttle Columbia Launch.

Space Shuttle Columbia Launch.

STS-123 - night launch.

STS-123 – night launch.

STS-130 - night launch.

STS-130 – night launch.

STS-135: the final launch of the Space Shuttle Programme. This is Atlantis as it launches from Pad 39A on Friday, July 8, 2011, at NASA's Kennedy Space Center in Cape Canaveral.(Credit: NASA/Bill Ingalls).

STS-135: the final launch of the Space Shuttle Programme. This is Atlantis as it launches from Pad 39A on Friday, July 8, 2011, at NASA’s Kennedy Space Center in Cape Canaveral.

Lt. Col. Gabriel Green and Capt. Zachary Bartoe patrol the airspace in an F-15E Strike Eagle as the Space Shuttle Atlantis launches May 14, 2010, at Kennedy Space Center, Fla. (Capt. John Peltier, USAF).

Lt. Col. Gabriel Green and Capt. Zachary Bartoe patrol the airspace in an F-15E Strike Eagle as the Space Shuttle Atlantis launches May 14, 2010, at Kennedy Space Center, Fla. (Capt. John Peltier, USAF).

Space

Space Shuttle Discovery over Switzerland.

Space Shuttle Discovery over Switzerland.

Space Shuttle Discovery approaching Mir.

Space Shuttle Discovery approaching Mir.

Space Shuttle Discovery over our blue planet.

Space Shuttle Discovery over our blue planet.

Space Shuttle Endeavour attached to the International Space Station on May 23, 2011 (taken from Soyuz TMA-20).

Space Shuttle Endeavour attached to the International Space Station on May 23, 2011 (taken from Soyuz TMA-20).

Space Shuttle Atlantis docked with the segmented Mir.

Space Shuttle Atlantis docked with the segmented Mir.

Landing

Space Shuttle Endeavour Landing.

Space Shuttle Endeavour Landing.

Space Shuttle Atlantis Vapor trails as it approaches Runway 15 on the Shuttle Landing Facility at NASA’s Kennedy Space Center at Cape Canaveral.

Space Shuttle Atlantis Vapour trails as it approaches Runway 15 on the Shuttle Landing Facility at NASA’s Kennedy Space Center at Cape Canaveral.

Space Shuttle Atlantis landing at KSC (STS-122).

Space Shuttle Atlantis landing at KSC (STS-122).

Retirement

Thousands of spectators gathered in front of the Forum in Inglewood, Calif., as the space shuttle Endeavour stopped temporarily for a celebration as it headed overland to its new home at the California Science Center in Los Angeles on Saturday, Oct. 13, 2012. (NASA / Bill Ingalls).

Thousands of spectators gathered in front of the Forum in Inglewood, Calif., as the space shuttle Endeavour stopped temporarily for a celebration as it headed overland to its new home at the California Science Center in Los Angeles on Saturday, Oct. 13, 2012. .

The Space Shuttle Enterprise is towed by barge up the Hudson River in New York June 6, 2012 Photo Credit: (NASA/Bill Ingalls).

The Space Shuttle Enterprise is towed by barge up the Hudson River in New York June 6, 2012.

All images: NASA/Troy Cryder/Bill Ingalls.

Related content

I highly recommend a couple of videos.

First, here is the “Space Shuttle: The complete missions” – a Nature Video. It was put together by Adam Rutherford – all 135 missions spliced together into a fantastic 8 minute movie.

NASA’s 30-year Space Transportation System (STS) program came to an end on 21st July 2011. The Space Shuttle fleet delivered the Hubble Space Telescope, the International Space Station, and dozens of satellites, space probes, crew and supplies. Two Shuttles were lost: Challenger in 1986 and Columbia in 2003. The touchdown of Atlantis at Kennedy Space Center marked the end of an era, after 135 missions. This video shows all of them in chronological order.

The second is a BBC special: Space Shuttle: The Final Mission. It’s an excellent documentary that was presented by Kevin Fong.

It seems to be available on You Tube at the moment…though I guess it might get taken down by the BBC.

Related Posts

Space Scenery series.

Posted by: Kash Farooq | April 7, 2013

Frank Drake and the Arecibo Message

In 1974, a specially encoded message (that become to be known as the Arecibo Message) was broadcast into space towards the globular cluster M13 in the constellation of Hercules:

Globular Cluster M13 in Hercules

Globular Cluster M13 in Hercules. Image acquisition by Jim Misti, image processing by Robert Gendler. http://www.robgendlerastropics.com

The message was broadcast by Frank Drake from the enormous (you can see road and a car in the foreground) Arecibo Observatory radio telescope in Puerto Rico:

The Arecibo Observatory

The Arecibo Observatory. Image courtesy of the NAIC, a facility of the NSF.

The message was intentionally sent to broadcast Earth’s existence to any alien civilisation that might be listening. No permission was obtained from the rest of the planet. Frank Drake just decided to do it. Sir Martin Ryle (who was the Astronomer Royal at the time) wrote to Drake questioning the wisdom of this act. However, even if some hostile civilization received (and understood) the message, we don’t need to be overly concerned – M13 is 50000 light years away.

Just 1679 bits of information were transmitted. Compared to today’s data quantities, this is a tiny amount of data. Even so, in 1679 bits, an impressive amount of information was broadcast. The message was carefully designed by Frank Drake and Carl Sagan to provide as much information as possible in this small data packet.

Why was the message encoded in 1679 bits? 1679 is the product of two prime numbers (23 and 73), and mathematics is the only common language humans could possibly have with an alien civilization. The intention was that the receiver would convert the incoming 1679 binary bits into a 23 by 73 rectangle, colouring in the ‘ones’ and leaving the ‘zeros’. This would result in this:

The Arecibo Message

The Arecibo Message

The colours have been added to distinguish between the different areas of the message.

Message Part 1 – The Numbers 1 to 10

The white dots at the top of the message represent the numbers 1 to 10, in binary. Each dot in the bottom row is ignored (it just signals the start of number). Hence we have 1, 10 (decimal 2), 11 (decimal 3), etc.

Message Part 2 – Elements found in DNA

The next section (purple) represents the atomic numbers of the elements found in DNA: hydrogen, carbon, nitrogen, oxygen, phosphorous. Again, ignore the bottom row – so the first column has one dot in it, signifying the atomic number of hydrogen.

Message Part 3 – Nucleotides

The green section follows on from the elements presented in part 2 and shows the molecular formula of each nucleotide – e.g. the top left collection of dots is deoxyribose C5OH7 and needs to be read as (ignoring the bottom row again): 7 atoms of hydrogen, 5 atoms of carbon, 0 atoms of nitrogen, 1 atom of oxygen, and 0 atoms of phosphorus.

The next symbol is adenine (C5H4N5), then Thymine (C5H5N2O2), etc.

Message Part 4 –  The DNA Double Helix

The blue curved lines represent the DNA double helix, with the white vertical line representing the number of nucleotides in DNA.

Message Part 5 – Humans

This red symbol clearly represents a human. Apart from the obvious shape, there is also information to left and the right of the red figure.

The white bits on the left represent the binary number 1110.

Note: this image from Wikimedia Commons has the number on the left – I’ve seen other images with the number on the right. It makes more sense on the right, as then it would actually read 1110.

1110 is 14 in decimal. The message was broadcast at frequency 2380 Hz, which is equivalent to the wavelength 12.6 cm. 14 x 12.6 cm = 176.4 cm. This is the average height of a human.

The white bits on the right of the red human form represent the population of Earth at the time the message was broadcast – which was just over 4.25 billion in 1974.

Message Part 6 –  The Solar System

The yellow dots represent the Solar System, with the large Sun on the left and Earth slightly raised to show that “We Are Here”. Also, the human form is directly above the raised dot, again showing where we live.

Message Part 7 – The Arecibo Observatory

Finally, the bottom image represents the Arecibo Observatory dish that broadcast the message with the dots at the bottom representing the diameter of the dish.

What happens when you give this message to a human?

As you can see, Sagan and Drake managed to cram a lot of information into such a small number of bits. Whether an alien civilization would be able to decode the message or not is another matter. Drake presented the binary bits to some of his colleagues – only some of them were able to partially decode the message; no one was able to fully decode it.

Posted by: Kash Farooq | March 31, 2013

The Pod Delusion Interviews

The Pod Delusion Logo

I started contributing to the Pod Delusion a few years ago, starting with monologues, but now I mainly interview people.

I love it! I get to speak to lots of interesting people. Oh, and as a by-product, The Pod Delusion gets some content too. ;)

Occasionally, potential interviewees ask me for “references” – i.e. ask me who I have previously interviewed. So I thought I’d keep a track of my interviews here. I’ll include any interesting follow up links to related blog posts and articles, and even interview transcripts if I’ve created them.

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