Brad Guth wrote:
>
> My URL has much to do with the discovery of "GUTH Venus"
> http://geocities.com/bradguth
>
> One of my questions has to deal with a manned mission, which may need
> to utilize the orbit station L2, as an orbit situated so as to sustain
> life onboard the spacecraft for several months to perhaps years.
>
> If the space craft were to be represented by upwards of 1000 tons
> mass, what would the calculated L2 become?
>
> The same calculation at 500 tons and perhaps 100 tons.
>
> I've asked this of many NASA types and they exploded. Please don't
> explode on my account. A good lead to an astro/gravity-calculator may
> do just fine.
*BANG!*
Just kidding. I presume that by "the orbit station L2" you mean the
(unstable) second Lagrange point of the Sol/Venus pair?
The location of this point is not affected to first order by placing a
mass there. The only effect would be a second-order effect due to the
perturbation, due to the station's mass, of the orbit of Venus [and, if
you want to get truly silly, of the position of the Sun.]
As in this case "order of magnitude" is essentially the ratio of the
mass of the station to that of the Sun [not of Venus, which is the
object being moved...] you can see that the "empty" location of L2 would
continue to be valid in the presence of any object we could put there,
probably to within a micron.
That said, I feel I must add something on the subject of the NASA Venus
images that you think show artifacts. I do not know if you are familiar
with either marquetry or gemmology. If you have any experience with the
first, you will probably know about the American red gum tree
(_Fluidambar_styrax_ - what a beautiful name!). Its veneer is much
sought after by marquetarians, because a slice cutting through both
heartwood and sapwood often contains a detailed desert scene, with
cirrus clouds in the sky and sand dunes on the ground. The dunes are
often even silhouetted against the skyline.
There are also sedimentary rocks that are used for jewellery which,
when sliced, regularly show landscapes in which the eye "recognizes"
many details. Again, I have seen a poster with an entire alphabet made
up of photographs of details from butterflies' wings; and while *some*
resemblances between such markings and other creatures are presumably
evolutionarily advantageous in that the resemblance is to something a
predator will avoid, this hardly explains the sometimes near-perfect
human skull seen on the Death's-Head Moth. [You will have seen it on the
cover of most paperback editions of "The Silence of the Lambs". On some
of these it's retouched, so that the skull itself is made up of several
ghostly female bodies; but the basic image is fairly accurate.]
What I'm getting at is that people tend to underestimate the ability of
naturally-arising phenomena to mimic other things, without intelligent
intervention. You should also be aware that these photographs were not
taken using light, but by radar. If I remember correctly, they were not
even taken as images, but as a linear scan pattern, assembled into an
image by a computer on Earth. The bright lines are NOT
differently-colored regions, or uniformly higher (or lower) than those
around them; they are cliffs between terraces. If you imagine that the
model is on a table top, made of dark clay, and lit from the side, it
will be easier to interpret. Or think of a landscape seen at sunset.
-Robert Dawson
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