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Deleted member 473
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Interesting Items...
- Thread starter Black Hole
- Start date
OP
Black Hole
May contain traces of nut
I saw a (repeat, I think) programme on BBC FOUR last night about Wild China.
It explained about bamboo going through flowering cycles once in up to 100 years, all at once, and after it flowers it dies off. Giant pandas have to have a large enough range that when an area of bamboo dies off, they can move somewhere else where there is a different variety of bamboo that hasn't flowered, and encroachment of mankind is limiting their range and putting survival in the wild at risk. So far, fair enough.
But it also showed a rodent like a cross between a rat and a mole (I think it was called the cane rat) that lives in underground tunnels, but feeds on young bamboo stems by dragging them down from below (all you see above ground is a stem disappearing downwards!). The programme didn't say what happens to this rat when all the local bamboo dies off - I presume they can't simply move en mass somewhere else!
There were also tiny bats, so small a whole family group can live inside one section of a bamboo stem. They were described as the world's smallest mammal, the size of a bumble bee.
It explained about bamboo going through flowering cycles once in up to 100 years, all at once, and after it flowers it dies off. Giant pandas have to have a large enough range that when an area of bamboo dies off, they can move somewhere else where there is a different variety of bamboo that hasn't flowered, and encroachment of mankind is limiting their range and putting survival in the wild at risk. So far, fair enough.
But it also showed a rodent like a cross between a rat and a mole (I think it was called the cane rat) that lives in underground tunnels, but feeds on young bamboo stems by dragging them down from below (all you see above ground is a stem disappearing downwards!). The programme didn't say what happens to this rat when all the local bamboo dies off - I presume they can't simply move en mass somewhere else!
There were also tiny bats, so small a whole family group can live inside one section of a bamboo stem. They were described as the world's smallest mammal, the size of a bumble bee.
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Deleted member 473
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Deleted member 473
The chinese eat bamboo rats!
OP
Black Hole
May contain traces of nut
They certainly didn't seem to mind tucking into live hornet larvae! Ugh. Maybe if they were cooked...
(The way they found the larvae in the jungle was to offer a grasshopper on a stick to the hornets that were buzzing around a banana flower. When one started work on the grasshopper, trying to chew a bit off to take home, they lowered the stick and - with the hornet distracted - slip a noose of fine twine around its abdomen with a piece of white feather on the end. When the hornet flew off with its prize, they could track it back to the nest by watching the feather.)
(The way they found the larvae in the jungle was to offer a grasshopper on a stick to the hornets that were buzzing around a banana flower. When one started work on the grasshopper, trying to chew a bit off to take home, they lowered the stick and - with the hornet distracted - slip a noose of fine twine around its abdomen with a piece of white feather on the end. When the hornet flew off with its prize, they could track it back to the nest by watching the feather.)
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Deleted member 473
Nah!
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Deleted member 473
Nobody has mentioned the NASA planets yet, have they? Within communication distance, too!
https://exoplanets.nasa.gov/news/14...ze-habitable-zone-planets-around-single-star/
https://exoplanets.nasa.gov/news/14...ze-habitable-zone-planets-around-single-star/
OP
Black Hole
May contain traces of nut
This column is headed "Interesting Items" - there's nothing particularly interesting about them despite the huge news splash yesterday intended to boost NASA's approval rating.
Despite what was announced, the only thing known about these exoplanets is orbital period. The mass of the star can be estimated, from which their orbital distances can be derived, and their perturbing effect on the star's spectrum then indicates masses of the planets. The precise detail of any extinction of starlight due to occultation can be used to estimate diameters (given orbital distance, assuming there is any occultation at all which would be a very slim chance but I think probably applies here), and therefore density.
Density + size hints whether the planet may be small and rocky (like Mercury, Venus, Earth, Mars) or large and gassy (like Jupiter, Saturn, Neptune, Uranus). Orbital distance, assuming orbits are low eccentricity, + star brightness indicates surface temperature and compatibility with liquid water (not the existence of water). If there were occultations, it might be possible to detect characteristics of any planetary atmosphere in the star's spectrum (but it would be exceedingly subtle).
So, the announcement is the product of a long chain of conjecture - an educated guess, but potentially very wide of the mark. The only really remarkable thing about it (compared with other exoplanet discoveries) is the number of planets.
As for communications distance... if you can wait 80 years for a reply, by all means have a go!
Despite what was announced, the only thing known about these exoplanets is orbital period. The mass of the star can be estimated, from which their orbital distances can be derived, and their perturbing effect on the star's spectrum then indicates masses of the planets. The precise detail of any extinction of starlight due to occultation can be used to estimate diameters (given orbital distance, assuming there is any occultation at all which would be a very slim chance but I think probably applies here), and therefore density.
Density + size hints whether the planet may be small and rocky (like Mercury, Venus, Earth, Mars) or large and gassy (like Jupiter, Saturn, Neptune, Uranus). Orbital distance, assuming orbits are low eccentricity, + star brightness indicates surface temperature and compatibility with liquid water (not the existence of water). If there were occultations, it might be possible to detect characteristics of any planetary atmosphere in the star's spectrum (but it would be exceedingly subtle).
So, the announcement is the product of a long chain of conjecture - an educated guess, but potentially very wide of the mark. The only really remarkable thing about it (compared with other exoplanet discoveries) is the number of planets.
As for communications distance... if you can wait 80 years for a reply, by all means have a go!
MikeSh
Well-Known Member
My feeling is that the search for alien life is driven more by a "there is life out there [from which we evolved] and we sure as neck are going to prove it" rather than a more open minded search for knowledge, which might stumble on extra-terrestrial life. But I suppose this gets donations rolling in.
I'm also of the Stephen Hawking persuasion - if said aliens do exist in an advanced form, we may not want to appear on their radar.
I'm also of the Stephen Hawking persuasion - if said aliens do exist in an advanced form, we may not want to appear on their radar.
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Deleted member 473
That applies to earth too.
I am not one to decide whether something should or should not be interesting to others. I merely make suggestions.
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Deleted member 473
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OP
Black Hole
May contain traces of nut
Wow!
Indeed, and ditto, but I may have made it more interesting.I am not one to decide whether something should or should not be interesting to others. I merely make suggestions.
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Deleted member 473
Exactly what they do: look for the absorption spectrum of water as a planet transits the star. And it is extremely subtle, but like a fingerprint for water.
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Deleted member 473
If you took all the DNA in your body and stretched it all out end to end, it would stretch from the sun to Pluto and back, 7 times. Apparently. Is that interesting?
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Deleted member 473
The known universe is made up of 50,000,000,000 galaxies. There are between 100,000,000,000 and 1,000,000,000,000 stars in a normal galaxy.
In our galaxy alone, there might be as many as 100 billion Earth-like planets. We are doomed!
In our galaxy alone, there might be as many as 100 billion Earth-like planets. We are doomed!
OP
Black Hole
May contain traces of nut
OP
Black Hole
May contain traces of nut
Not to me. Assuming it's true (and you have qualified it with deprecation "apparently"), it's just a random factoid with no practical benefit whatsoever.
Trev
The Dumb One
There are lots more of them about. Or hadn't you noticed, such as the Drake Equasion. Neither pass the 'So What?' test.
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Deleted member 473
So what?
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