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so here are pictures i will link below of different section of a study guide i am trying to complete. please explain at least one problem step by step from each link i really need help and it would be so appreciated you have NO IDEA.

http://i107.photobucket.com/albums/m317/so2cute4u2002/ScreenShot2013-02-13at120623AM_zps9e062219.png

http://i107.photobucket.com/albums/m317/so2cute4u2002/ScreenShot2013-02-13at15118AM_zps54eed560.png

 First of all my condolences to Dingo1 and his family.
If I was starting now I would take into consideration a some things which

took a long time to come to my attention. I think a table such as the one

here:
http://www.telescope.com/Articles/Current-Articles/Accessories/Choosing-

Eyepieces/pc/9/c/192/sc/196/p/99803.uts
can be made more specific taking a couple of addtional important priciples

into account.

1. The use of filters. The instructions for an H-beta filter indicates it

works best at an exit pupil of 4 to 5mm, or 3 to 5 if light polluted sky.

2. Contrast- Detecting faint fuzzies is all about contrast and filters is

not the only way to affect contrast. Increased magnification dims the sky.

In theory contrast remains the same but in practice a dimming of the sky

together with the increase in magnified image size improves the perceived

contrast in the eye. So the key is the image scale. But charts, articles and

guides I have seen about this are way too complex for practical use under

the stars. A more natural way to keep track of how much an eyepiece dims the

sky is not hard to figure. It so happens that decreasing the exit pupil by a

factor of 0.631 dims the sky by 1 magnitude per arcsecond squared. This

suggest a simple progression: starting with the 7mm exit pupil followed by

4.4, 2.8, 1.1, 0.7, 0.3 will let you explore the effects of 1 magnitude

dimming at a time which combined with the increase in image scale of the

corresponding increase in magnification makes for an interesting approach to

make the most advantage of contrast in locating faint fuzzies.

3. The limitation of the atmosphere. I find it a good idea to keep an

eyepiece to produce around 200x power because this is probably the average

maximum the atmosphere will allow a clear view of planets. Not necesarilly a

limit for "detecting" faint objects.

4. The limitations of the telescope. When the exit pupil is 1mm the

magnification is equal to the aperture of the telescope. This is the

magnification that will show the maximum detail. More magnification will

magnify the same detail but no additional detail will emerge from the image.
After this point three more eyepieces remain of interest. One would be an

eyepiece that will increase magnification by 50% more (exit pupil =0.67 and

one full sky magnitude dimmer). Another would be an eyepiece which decreases

the pupil by 50%. (exit pupil=0.5 this is the so often cited maximum

thoretical limit of the telescope). And yet another would be an eyepiece

which would let you stretch that theoretical limit a bit more in case you

own exceptional optics, say 0.3 exit pupil to reach the last full magnitude

sky dimness and explore if that contrast let you "detect" something

otherwise not seen. If you have an 8 inch or larger telescope you're

challenging the atmospheric conditions  with all of these since the 1mm

pupil which already took your magnification to 200x, but may be a good

choice for smaller telescopes or for the patient and brave.

5. Some characteristics of the eye. I read once  (See here:

http://starizona.com/acb/basics/observing_theory.aspx) that the optimum

resolution of the eye occurs between 2 and 3mm exit pupil, averaging on the

2.4mm. So an eyepiece to that effect may be a very satisfactory one.

So taking into account all these factors what exit pupils seem the more

tempting? (multiply the exit pupil by focal ratio to get the eyepiece focal

lenght)

1.Between 7mm and 6mm exit pupil is the widest angle, low power "finder"

eyepiece to help locate where you are in the sky. If the telescope has a

central obstruction the 7mm will probably be too big and the obstruction

will be seen in the eyepiece.

2. A 4.4mm exit pupil will decrease the sky brightness by 1 magnitude and be

useful with filters to find faint nebula.

3. A 3mm exit pupil still works with filters in polluted skies and without a

filter is close enough to 2.8 to approximate another 1 magnitude decrease in

brightness of the sky.

4. A 2.4 exit pupil is optimum for the eye resolution. If instead you

substitute this one for a 2mm exit pupil it will coincide with a half

maximum detail magnification of the telescope milestone.

5. A 1mm exit pupil will dim an addtional magnitude to the sky (from the

3mm) and is the maximum detail magnification.

6. An eyepiece which coincides with 200x or close (if none of the above)

this being the average atmospheric turbulence limit.

7. A 0.7 (0r 0.67) exit pupil will dim the sky yet one more whole magnitude

and will coincide with an extra 50% magnification over the 1mm Max detail

limit.
You may stop here or:
8. A 0.5mm exit pupil to enjoy the theoretical maximum limit of the scope.

9. a 0.3mm exit pupil to reach an extra full magnitude dimness of the sky.

Of course I'm not an eyepiece salesman and therefore I'n not asking you to

go get 9 or 10 eyepieces. In practice and thanks to Barlows it works out

differently. Here an example:

The telescope is 8"f/6:

1. 7x6=42mm eyepiece, not too common and may show the obstruction, so

6x6=36mm eyepiece is an alternative, even 35mm no need to be exact.

2. 4.4x6=26.4mm eyepiece. You can choose 25,26,27 no need to be exact.

3. 3x6=18mm eyepiece

4. 2x6=12mm eyepiece

5. 1x6=6mm eyepiece-this can be the 12mm with 2x Barlow
and you may stop here since you're at 200x.That's 4 eyepieces and a Barlow

If short of money skip the first one for later, keep the next three and the

Barlow. You get to dim the sky by 3 magnitudes plus.
If you have the money you can continue:

6. 0.67x6=4mm eyepice, or the 12mm with 3x Barlow. That's 300x!

7. 0.5x6=3mm eyepiece. Could get that 6mm at step 5 and use with the 2x

Barlow.
And at 400x I can see no reason to strain your eye looking into dimmer exit

pupils. You get an extra magnitude dimness (four in total) for an additional

eyepiece (4 in total and 2 Barlows if you skip step #1). The 0.3mm exit

pupil here produces 670x power that seems farfetched to me even for an 8".
Larger than 8" aperture telescopes let you stop magnifying earlier and

therefore save you some money in eyepieces (irony).

Samller telescope benefit more from the trick of increasing magnification to

dim the sky. You spend less in the telescope but may need more eyepieces.
There are objects that will dissappear with increased magnification. This is

because in the complex charts and theory I mentioned before there is such a

thing as a threshold magnified size. So the benefit of the 1 magnitude steps

is to be able to go back and forth and see what works in an organized way.

How about a smaller Telescope?:

90mm f/5.5:
1. 7x5.5=38.5mm. Say 38mm eyepiece. Probably need a 2" focuser. 6x5.5=33mm

or 32mm.

2. 4.4x5.5=24.2mm, say 24 or 25mm eyepiece.

3. 3x5.5=16.6mm. Say a 17mm eyepiece.

4. 2x5.5=11mm.

5. 1x5.5=5.5mm. Say the 11mm with 2x Barlow.

6. 0.67x5.5=3.7mm. Say the 11mm with 3x Barlow. We are at 135x power.

7. 0.5x5.5=2.75mm. Here you may opt for an 8mm for use with the 3x Barlow.At

185x this is close enough to the 200x of the atmosphere and you could stop

here. But:
8. 0.45x5.5=2.5mm. Here you may get a 5mm for use with the 2x Barlow. We are

at 200x. A good idea here is to choose either this step or the one before

and save an eyepiece, since they are so close.

9. 0.3x5.5=1.65mm. This is the 5mm with 3x Barlow. This hints at what to

choose in the previous step (skip the 8mm eypiece step). We are at 300x.

With this telescope it will not show nice planets at that magnification, but

the idea at this point is to "detect" a fuzzie for which this size happens

to be the "Threshold" for visibilty. Notice I say "detect" wich is a

completely different experience from "seeing it clearly". You have dimmed

the sky by  5 magnitudes per square arcseconds. It took 5 eyepieces and 2

Barlows. Using this scale from a site Yale showed me long ago (it's in a

sticky above):
http://mysite.verizon.net/vze55p46/id18.html
This can get you from say an 17 MPSAS sky to a 22 MPSAS. As dark as the most

naturally ocurring dark sky...which is bright...

I quote from myself in that sticky:
"I...try to come up with some kind of guideline by keeping track of both

Magnitude and Surface brightness on different objects as seen from different

sky conditions and different scopes."

Well this is it.

On Skylab the crew ran around the ring of equipment lockers, generating artificial gravity.  They also torqued the station, moving it out of its proper orientation.
   
The BA330 from Bigelowaerospace has an inner radius 3.35 meters.  Assume an astronaut is 1.6 m tall and runs at v = 3.6 m/s measured at the feet.
   
The acceleration at the feet is v^2/r = 3.6^2/3.35 = 3.85 m/s^2  The rotation period is 2 PI r / v = 5.85 s.
   
At head height the radius is 3.35 - 1.6 = 1.75 m, head speed 2 PI 1.75 / 5.85 = 1.88 m/s.   Acceleration at head is 1.88^2 / 1.75 =  2.02 m/s^2.
   
These accelerations are close to those of Mars or Luna.  Are they sufficient to counteract freefall degradation if experienced an hour a day?  Three hours a day?
   
To reduce station torque astronauts could run in pairs in opposite directions.  In quads with each pair spaced 180 degrees apart to reduce wobble.
   
Inside living cells there are components with settling times on the order of minutes.  Giving them time to accumulate on one wall of the cell may be important to long-term health. CL Strong, or http://www.pnas.org/content/97/15/8364.full 

Would sweat run toward the feet at these low accelerations?   Moving thru the air would aid cooling.
   
On Mir, Shannon Lucid cycled in resonance with the solar panels, with alarming results.  The frequency of pounding feet should be checked against frequencies of the station.
   
Would a runner suffer from vertigo?  Experience with Giuseppe Scuderi’s centrifugal running track indicates it may not be a problem.    www.lovelandmagazine.com/2004/07/italy_centrifug.html
   
Can anyone point me to research in partial gravity?  Is the inner surface of a BA330 suitable for running?  Strength, traction, other?
   
Melcon37

 

Dears,
  I am investigating a way to make an engine that can run continuously. Currently, my result is so positive.
 
 1. Tools and facilities:
 - The main component of this model is a wooden toy with dragonfly shape. Its head is a rectangle which is curved upward, with long tail
 - A sharp pillar
 - A medium sizes magnet
 - A tiny magnet
 
 2. Model
 - Stick the tiny magnet under the tail of dragonfly shaped specimen. The gravity of magnet makes this specimen settles down toward the tail.
 - Then, touch the sharp peak of the rectangle head of the specimen very slightly into the top of the pillar. It makes the balance status of this dragonfly toy is very unstable. It is very easy to drop down
 - Put the medium sized magnet at the base of the pillar so that its upward pole is the same as the downward pole of the tiny one (i.e. south to south, or north to north), and they are face to face as shown in attached screenshot
 - Keep the whole system in an insolated room, with all doors and windows are closed to prevent air wing influence.
 
 3. Operation:
 - The attraction force between 2 magnets makes the tail of the specimen is pulled down slightly, before it is up again. Then a new period starts with the up and down movement of the specimen tail, again and again etc.
 - The position of the medium sized magnet is adjustable so that it can give best result to the movement of the specimen. If the distance between magnets is so far, the force intensity is so weak to result in movement. Otherwise, the strong attraction force from the medium sized will also prevent the specimen from moving.
 
 I let my model there overnight to make sure that there is no stopping. And luckily it does not stop until now.
 
 I post my article here so that any interesting individual can follow and replicate my experiments.
 

 All of my expectation that you can contact me and replicate my experiment
 
 Thinh from Vietnam

Sorry, been a bit busy with the telescope

http://news.yahoo.com/orphan-alien-planet-found-nearby-without-parent-star-122308193.htmlRecent published artical in regards to planet sized objects moving through space, not associated with a star

The speed of sound is exceding slow in comparison to the speed of light.  With sound you can tell the difference in volume and pitch as you approach it's speed.  That is called the dopler effect.  How that works is easy to visualize. use a boat on a pond, as it moves forward, note the bow wave, the water pushed in front of the boat.  Sound does the same thing.  In particle physics, the same effect occurs.  The speed of thought has not been measurable, we do not have the technology to measure it

Welcome

Welcome here.

Surrounded with rays square, with an "eye" in the middle, symbolizes a human. More exactly a square with two paralel lines in the middle which symbolize axles of time, and with two paralel lines at each side of the square, outside of the square, perpendicular to each side, which are also axles of time. The symbol in such a simple way describes one of kinds of natural creature.. That symbol we have to avoid manipulations.