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Lonecat in Orbit 11 |
 HELLO again everybody! This is Lonecat in Orbit with an overview of this week's astronomical news gleaned from the Astronomy Forum of The BOOK OF THOTH. I'd like to start of this week's edition almost literally with a bang. You can't actually hear anything but the sight of the re-entry and break-up of the Jules Verne European space-tug is impressive indeed. Go to this link to see some terrific still shots and then see, on your right-hand side, at the top of the column, a silent video of the re-entry. This beats fireworks!
http://tinyurl.com/4vmgrl
THE INSIGNIFICANT EARTH (?)
"It makes the earth look insignificant" suggested Pencil when he sent us this almost overwhelming series of images which show first the Earth and then the Earth and Moon and then Mars is added and so on, giving us an impressive comparison of the size of our home planet with that of progressively larger celestial bodies. I was left aghast at how really very tiny Earth is in comparison with the largest known star. However, I don't feel that we should consider the Earth to be "insignificant". Earth is a large planet if we compare it with things smaller and there are many things far smaller than Earth. We could say that subatomic particles are "insignificant" yet without them the universe would exist. Size whether it be great or small is a relative conception and exists only when compared with something else. Is a sphere large or small? It depends on something with which we compare it. The Earth is still highly significant. At least, that is the way I see it.
Image slideshow
THE MAKING OF...A ROCKET!
Now see these pictures taken at the factory where the Falcon rockets are built. I have always wondered how rockets can stand up under their own weight together with that of the fuel they have to carry. I suppose that that is why we see rockets on the launch-pad firmly embraced by by a series of mechanical "arms" which release the rocket only after it can be supported by the thrust of the fire from the combustion chamber.
http://tinyurl.com/48a7fd
FRACTAL UNIVERSES
Here now is a theory involving a fractal of universes in every fundamental particle in this universe where our universe is in a fundamental particle in a much larger universe sent in to us by AlexBeck7. I have read the text but find I would need to study it in greater depth to be able to pass a considered opinion. However, I like the idea that the universe we know may be "only" a fractal of a much bigger universe. It bears thinking about. Read it for yourselves and give us your opinions.
http://tinyurl.com/3uk55q
WHITE-TIGER'S EXPLANATION OF PLANETARY ORBITS
Iluminatus Rex started a good bit of debate this week with his question about planetary orbits:
My understanding is that the planets(or the materials composing them) were flying through space at some point in the extremely distant past and were caught in the Sun's gravitational pull, which changed the planets' course and caused them to revolve in a circle around it. But if this were the case it seems the planets should have steadily lost momentum and began to revolve slower and slower until they stopped moving at all. If not eventually fell into the Sun itself when their propulsion dipped below the force of the gravitational pull.
So I'm wondering, what force keeps the planets revolving in seemingly perpetual motion? Or if it's inertia, why doesn't the Sun's gravity acting on them become the outside force that terminates their trajectory?
Whitetiger's reply was...
Took longer than I thought to do the graphic. Got busy with domestic things.
This is a really crude and dirty quickie drawing just to help visualisation. Nothing in it is to scale at all. Obviously the yellow bit is the sun, the big circle is the orbit, and the little ones are the orbiting planet in different positions. On the lower planet drawing, the green line is it's instantaneous vector sum... if the sun disappeared all at once that line represents the direction the planet would fly off under it's own inertia. Notice that the line is tangent to the orbital circle. In the upper planet location, the green line is the direction the planet was headed originally down below. The red line represents the pull of the sun's gravity. Since a thing can move only one direction at a time, when several forces act on it at once it's movement will be in the direction of the sum of those forces. The blue line is the new vector solution with the sun's attraction plotted against the original green vector.
Obviously this happens steadily, instant by instant, and not in jumps as in the illustration, but the big spread makes it easier to illustrate the idea. As long as the forces of momentum and gravity balance to produce a vector sum tangent to the orbital arc, the planet will just keep trucking along.
One more point... the planet is constantly falling toward the sun because the pull of the suns gravity is always there. The gravitational attraction is constantly feeding energy into the planet's motion. This is why it is possible to use a gravitational slingshot effect on spacecraft and get them moving faster as they pass a planet. The planet keeps on trucking because it's motion is constantly "fueled" by the force of gravity.
Tiger
Nice drawing there, WhiteTiger, and thanks for the explanation. It is a pity that the drawing did not come out in the present posting but readers can always check back on the Astronomy Forum if they'd like to see it. You must show me how to do graphics like that, Tiger. Anyway, any person reading this who wants more on this subject can pop over to the Astronomy Forum and see how the debate continues.
THAILAND PLACES SATELLITE IN ORBIT
On Wednesday, October 01, 2008, a Thai Remote Sensing Satellite atop a Russian converted Dnepr Ballistic Missile, blasted off into Space from an Underground Silo at the Yasny Space Base in Southern Russia, at 02:37 AM (EDT) / 06:37 AM (GMT).
The Thailand Earth Observation Satellite (THEOS) was deployed into a 425 Mile (684 Kilometres) high Sun-Synchronous orbit about a half-hour later, with it at a later stage using its own propulsion system to raise its orbit height to +500 Miles (805 Km).
Personally I get the shivers just thinking that this satellite was launched into orbit from a converted intercontinental ballistic missile fired from an underground silo. Could this satellite launch have also served as a test for launching I.C.B. M.s? Anyway, let's look on the bright side. The satellite itself was able to shove itself into a higher orbit under its own steam so to speak. Read the story here http://tinyurl.com/54xjq3
THE SOUNDS OF MARS
I am looking forward to hearing the sounds recorded on Mars. I remember, many years ago when I was working for the radio, that I was interviewing a space scientist who was working with NASA here in Spain. During our conversation I suggested to him that when they sent the next mission to Mars they should include stereo microphones for Mars has an atmosphere and this would transmit sound waves. He answered "Say, that's not a bad idea!"
http://tinyurl.com/4eklq4
Pencil wrote in to tell us not to forget to watch the sky after Sundown he says:
"Both Venus and Jupiter can be seen in the sky around 3/4 hour after sunset, Venus should be seen setting southwest, while for Jupiter is more south.
Next month should see some fantastic sights, both Venus (still southwest) and Jupiter (now setting south southwest) are closer together in the Sagittarius all month, at the end of the month they are the closest together with a moon that is in crescent stage near to them."
I for one will be sure keep my eyes peeled for these two beautiful planets. Here is a picture that I was reminded of by Pencil's posting. http://tinyurl.com/4ytynv
I came across this picture of the very first rocket launch from Cape Canaveral. It really is quite a historic picture. I well remember this type of rocket which was known as the V2 falling on London in the second world war. I'm so glad that something good finally came of it! http://tinyurl.com/4b3cqy
To end this week's orbit I thought I would include this very beautiful photo of a solar prominence. It was the picture of the day for yesterday, Saturday the 4th of October. Just click onto this link: http://apod.nasa.gov/apod/
I'll be back again next week at the same time. Take care of yourselves. Lonecat
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