Astronomers discover planet made of diamond

Harpo

Getting away with it
Joined
Sep 23, 2006
Messages
3,053
Location
The edge of the world. Yes, really.
http://www.reuters.com/article/2011/08/26/us-planet-diamond-idUSTRE77O69A20110826

(Reuters) - Astronomers have spotted an exotic planet that seems to be made of diamond racing around a tiny star in our galactic backyard.
The new planet is far denser than any other known so far and consists largely of carbon. Because it is so dense, scientists calculate the carbon must be crystalline, so a large part of this strange world will effectively be diamond.
"The evolutionary history and amazing density of the planet all suggest it is comprised of carbon -- i.e. a massive diamond orbiting a neutron star every two hours in an orbit so tight it would fit inside our own Sun," said Matthew Bailes of Swinburne University of Technology in Melbourne.
Lying 4,000 light years away, or around an eighth of the way toward the center of the Milky Way from the Earth, the planet is probably the remnant of a once-massive star that has lost its outer layers to the so-called pulsar star it orbits.
Pulsars are tiny, dead neutron stars that are only around 20 kilometers (12.4 miles) in diameter and spin hundreds of times a second, emitting beams of radiation.
In the case of pulsar J1719-1438, the beams regularly sweep the Earth and have been monitored by telescopes in Australia, Britain and Hawaii, allowing astronomers to detect modulations due to the gravitational pull of its unseen companion planet.
The measurements suggest the planet, which orbits its star every two hours and 10 minutes, has slightly more mass than Jupiter but is 20 times as dense, Bailes and colleagues reported in the journal Science on Thursday.
In addition to carbon, the new planet is also likely to contain oxygen, which may be more prevalent at the surface and is probably increasingly rare toward the carbon-rich center.
Its high density suggests the lighter elements of hydrogen and helium, which are the main constituents of gas giants like Jupiter, are not present.
Just what this weird diamond world is actually like close up, however, is a mystery.
"In terms of what it would look like, I don't know I could even speculate," said Ben Stappers of the University of Manchester. "I don't imagine that a picture of a very shiny object is what we're looking at here."
(Reporting by Ben Hirschler; Editing by Sophie Hares)
 
This sounds massively speculative to me. It seems the only real thing they know about this planet is its mass. They're inferring something about the size of the planet (not sure how) to work out the density. And it seems they're entirely guessing about the physical makeup of the planet. But oh well.
 
Imagine if it had rings around it, kind of a role reversal heh.
 
"The measurements suggest the planet, which orbits its star every two hours and 10 minutes, has slightly more mass than Jupiter but is 20 times as dense ... "

Science - thank the gods - is chiefly concerned with speculation. But this speculation is not fuelled by imagination or fantasy but by the best available data. Of course, scientific knowledge adapts to new data and further speculation.
 
From very big diamonds to very small ones:

I've recently watched a you tube talk on nano diamonds, which are carbon atoms arranged in the diamond crystal lattice or 'cage' as they call it. 'Nano' is a word much abused: a teaspoon full of these nano diamonds would be enough to give everyone on earth two billion of them, and still have some left over ... :)

EDIT: Harpo, some pulsars spin as fast as you describe, others slower. The slowest revolves once every 2.5 seconds or so. They all have a different rate of rotation, which makes them good galactic 'lighthouses' for navigation purposes.

A neuteon star (pulsar) is one that just nearly became a black hole. The electrons are compressed back into the nucleus of the atoms, to form neutrons. A teaspoon of neutron star material would weigh as much as a few billion aircraft carriers ...

LADY LARA: Carbon assumes maximum mass when the atoms are arranged in the diamond lattice. A diamond is quite a heavy stone. So it's a fair and reasonable assumption.
 
Last edited:
Maximum density do you mean?

Anyway, I guess I need to read the actual paper to know what evidence they have, but the quotes in the OP don't give any reason for why they think it's made of carbon, or for how they have any idea of the density of the planet.
 
Detailed explanation in this week's New Scientist. The words used are 'extreme speculation' I seem to remember.
 
I wonder when science moves beyond being science and into being art and creative writing, heh. "Extreme speculation" when taken to extremes, will cease to be science at all, as I could speculate a whole lot of stuff, and often do!
 
Science is a method. Fanciful speculation may be required in an attempt to model what has been observed. Models that survive testing may help us further understand the world.

However, scientists and reporters (and readers) should be conscientious about what is reported as observation, what is fact (confirmed observation), and what pure speculation.

Just because a "scientist" said it does not make it true.
 
Science is a method. Fanciful speculation may be required in an attempt to model what has been observed. Models that survive testing may help us further understand the world.

However, scientists and reporters (and readers) should be conscientious about what is reported as observation, what is fact (confirmed observation), and what pure speculation.

Just because a "scientist" said it does not make it true.

Still, you know, if they said they'd found a world made of graphite, or sulphuric acid, it would be: "Oh, how interesting" (as in not).

It's only because of the value our civilization places on diamonds that it matters to anyone. There's no particular reason a world shouldn't be made of diamond, within the reasonable possibilities of science? :)
 
A world made of graphite would be cool! The universe's largest pencil! All we need is a world made of paper, and we'd be good to go.

And a world of sulphuric acid would be enormous fun too - Venus is kind of that way anyway isn't it, it's atmosphere is full of sulphuric acid (as well as high temperatures and great pressures)? I guess it's not all made from sulphuric acid, but heading that way.

Now for the worlds made of gold, silicon, silicone, and hot dogs.
 
I had a look for the actual paper but didn't manage to find it (not that I looked for more than 5 or 10 minutes). I can't really see how they've managed to find anything other than the planet's mass though. Anyhing about its density, and particularly what its made of, must surely be highly speculative.
 
They may well know its size in which case it's mean density can be calculated. One way they calculate the size I believe is by how much reduction we see in the light of the star whilst the planet is transiting it.
 
I had a look for the actual paper but didn't manage to find it (not that I looked for more than 5 or 10 minutes). I can't really see how they've managed to find anything other than the planet's mass though. Anyhing about its density, and particularly what its made of, must surely be highly speculative.

Do you really look liker Laura Croft?
 
They may well know its size in which case it's mean density can be calculated. One way they calculate the size I believe is by how much reduction we see in the light of the star whilst the planet is transiting it.

There's no mention of that in the article though, just that they measured the wobble due to the differences in the timings of the pulses. In any case, neutron stars are so small that any planet would totally obscure its disc, so you couldn't work out its size.


Oh, and I don't know who Laura Croft is...
 
They may well know its size in which case it's mean density can be calculated. One way they calculate the size I believe is by how much reduction we see in the light of the star whilst the planet is transiting it.

And suppose a Jupiter-like planet only "grazed" the star in a partial eclipse? The assumption would be that a tiny, very dense planet made transit.

Still, I seem to recall once reading a speculation that Jupiter itself had a diamond-like core under all the clouds. George Pal's 1952 The War of the Worlds begins with a tour of the Solar system, illustrated by Bonestell paintings, and Jupiter's surface is described as mountains and cliffs of ice and running lava.

The world of diamond may exist, or it might be a wildly wrong best guess based on extremely limited data.
 

Back
Top