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"Court Martial" (and other episodes). They can't maintain orbit without engines.

Guess what, no object in orbit can maintain it's orbit without propulsion. Space isn't a perfect vacuum.

References
D. A. Vallado, et. al.
Australian Space Weather Agency
M. M. Moe et. al.

Now a ship the mass of the Enterprise and low cross-sectional area, won't have a decay time on the order of hours like they show in the show but it's orbit is always decaying.

Now the JJ Abrams Star Trek is riddled with errors.
In the first one there is no way a faster than ship should have problems escaping the gravitational pull of a blackhole if it has not crossed the event horizon yet.
In the second, when the enterprise is falling to earth, all of the crew should have been weightless.

There was one in Canada in 1989. http://www.ips.gov.au/Educational/1/3/12

Everything that exists is a part of nature, and is therefore by definition natural. However, that does not mean that we can claim to know what is real, and what is not, until we've actually tried to find out.

What I mean is this...

Just because it is politically incorrect to believe in ghosts, surviving dinosaurs, chi, etc... does not mean that they don't exist. But because they are politically incorrect, no serious scientists would ever sully their reputations on even considering researching such things.

That is a shame, because that kind of unscientific thinking (ie. not trying to prove/debunk assumptions) may have us miss out on some really nifty discoveries.

Some examples:

1. St. Elmos Fire was first thought by sailors to be angels harkening the end of long lasting storms. With todays all too common attitue that no serious scientist would consider testing for angels, sailors would probably still be considered superstitious. Luckily that's a relatively easily repeatable fenomenon, so people were able to study it and work out how it happens. (Cause: Electromagnetic.)

2. Some people claim to have heard clicking sounds from Auroras. However, not everyone hears them and recording them has been unsuccessful. So, does that mean that "some" people are just plain wrong? Unlikely, in my opinion, given that there's no benfit to making such claims. (Side note, an uncle of mine once heard it one bitingly cold night when walking.) Alaska Science Forum Explanation of Auroral Sounds (Cause: Unknown)

3. The Third Man Factor is when people in extreme conditions sense/see/interact with a “spirit” who eggs them on to think rationally and survive. In a book by Geiger a hypothesis is proposed: In an accidental discovery a girl had the left side of her skull open, and as doctors prodded a particular spot, she had a feeling of a presence next to her. Geiger’s hypothesis is that in extreme situations the brain might trigger this effect to give itself company in a lonely and stressful time, thus increasing the chance of survival. If so, then perhaps this could used deliberately on travellers to Mars and other hard to reach places. (Cause: Possibly psychosomatic.)

4. Apparitions have apparently been seen all over the world. However, when you look closely, you’ll find that aside from people scaring themselves, there are those who are certain of what they saw (though they won’t tell just anyone for fear of ridicule). All the stories that I’ve come across have certain elements in common. A hypothesis I have is best described as an analogy to magnetic storage: When active, we give off signals that can be recorded into surrounding materials. Later, when we’re passive (ex. at night when we’re no longer heavily distracted by day to tasks) some of us might be sensitive enough to read those recordings enough for the brain to conjure up an image (ie. a hallucination based on what’s recorded in the surroundings). Perhaps some materials are better recording materials than others, which may be partly why some areas are thought to be more “haunted” than others. It would also explain why hauntings can never be recorded, and also why some old places have a certain “feel” to them. If so, then perhaps in a few centuries time, this could possibly be harnessed to create new forms of information storage. (Cause: Unknown)

Do I believe in any of these? To be honest, I’d like to but, but must admit to being agnostic.

However, my point is simply to be more open minded, and critical, at the same time. But simply disbelieving outright is both disrespectful and cl

Again, if there are any problems with my English: I have no idea if CO2 cools or warms the Earth. I object to the AGW histeria because it's histerical, and in the areas where I have some knowledge the AGW activists are mistaken. I am only saying this: IPCC will suddenly discover that CO2 cools the Earth as soon as the Earth will start cooling and not a second after or sooner

These good people disagree that most of the photons come above the infrared band http://www.ips.gov.au/Educational/2/1/7

Even in the wikipedia graph, which is about how much energy in in the solar radiation, there are dips where the H2O and CO2 are "absorbed" in the atmosphere ... so, if the CO2 can send those "infrared" photons back to Earth, the same applies to the infrared photons send to the Earth by the sun. Which is greater ? I'll let the IPCC decide that when the time comes :)

Greenhouse effect is when you isolate a volume of gas near a source of heat instead of letting it convect naturaly and bring colder gas close to the source of heat. Greenhouses get cold during the night and the air in the greenhouse cools faster than the soil.

In space, some satellites actually tumbled out of control for several hours. NASA's TDRS-1 communication satellite recorded over 250 anomalies as high-energy particles invaded the satellite's sensitive electronics. Even the Space Shuttle Discovery was having its own mysterious problems. A sensor on one of the tanks supplying hydrogen to a fuel cell was showing unusually high pressure readings on March 13. The problem went away just as mysteriously after the solar storm subsided.

http://www.ips.gov.au/Educational/1/3/12

Service restoration took more than nine hours. This can be explained by the fact that some of the essential equipment, particularly on the James Bay transmission network, was made unavailable by the blackout. Generation from isolated stations normally intended for export was repatriated to meet Quebec's needs and the utility purchased electricity from Ontario, New Brunswick and the Alcan and McLaren Systems.

By noon, the entire generating and transmission system was back in service, although 17 percent of Quebec customers were still without electricity. In fact, several distribution-system failures occurred because of the high demand typical of Monday mornings, combined with the jump in heating load after several hours without power.

So... It caused a cascading effect, just like the most recent New York blackout, scary stuff if it occured across even a marginal size of the USA.

Some Useful Links.... http://www.nasa.gov/topics/earth/features/sun_darkness.html http://www.ips.gov.au/Educational/1/3/12

The rate of orbital decay is highly dependent on the surface area to mass ratio of the object. Typical debris has little mass and a lot of surface area, so it decays very rapidly when compared to a satellite or other massive object. This PDF explains it well, and you can look at TLE files to get a feel for actual decay terms.

The EGRS-3 Sat launched in 1965 is still orbiting in an 894 x 927 km orbit. TIROS-1 was launched into a 693 km x 750 km orbit in 1960, and is still merrily orbiting away 51 years later at 638 x 672 km.

The oldest sat still in orbit is Vanguard-1. It was launched into a rather elliptical orbit with the perigee near 650 km, but only massed 1kg!

Yes, exactly right, a big one in the right direction as opposed to all those small ones, or the big ones that all missed us in the last 15 years. There was a big power cut in Canada in 1989 due to a large solar flare. http://www.ips.gov.au/Educational/1/3/12

From the highest point of the ISS orbit (354.2 km), a regulation size golf ball (at least 42.67cm diameter and at most 45.93 grams), the orbit would decay in about 177 days, according to the program in this paper (and assuming no space weather): Satellite Orbital Decay Calculations.
The inputs to that program are:
0.04593 kg satellite mass
0.00143 m^2 satellite (frontal) area
354.2 km satellite orbit
(no space weather)

Even if the golf ball's effective area (well, the "frontal area", which is what we're concerned with) is reduced by half, the golf ball won't be up for even a year (354 days).

And this is assuming that the cosmonaut will be able to hit the ball in a roughly circular orbit! In other words, the ball must be higher than regulation mass (probably would have to be 200-300 grams, at least) in order to stay up that long (and probably to get the transmitter inside).

In other words, no real records for regulation golf balls will be broken (assuming it will be up there for at least a year).

Information and images of the flare activity is available from the Ionospheric Prediction Service (IPS) in Australia; especially the Solar page, that shows things like:
List of X-ray flares
Solar disk with flare image - Culgoora Observatory
Spectrograph 25-180MHz) - Learmonth Observatory
full disc image - Learmonth Observatory

Then, there is the comprhensive Space Weather page.

Information and images of the flare activity is available from the Ionospheric Prediction Service (IPS) in Australia; especially the Solar page, that shows things like:
List of X-ray flares
Solar disk with flare image - Culgoora Observatory
Spectrograph 25-180MHz) - Learmonth Observatory
full disc image - Learmonth Observatory

Then, there is the comprhensive Space Weather page.

Information and images of the flare activity is available from the Ionospheric Prediction Service (IPS) in Australia; especially the Solar page, that shows things like:
List of X-ray flares
Solar disk with flare image - Culgoora Observatory
Spectrograph 25-180MHz) - Learmonth Observatory
full disc image - Learmonth Observatory

Then, there is the comprhensive Space Weather page.

Information and images of the flare activity is available from the Ionospheric Prediction Service (IPS) in Australia; especially the Solar page, that shows things like:
List of X-ray flares
Solar disk with flare image - Culgoora Observatory
Spectrograph 25-180MHz) - Learmonth Observatory
full disc image - Learmonth Observatory

Then, there is the comprhensive Space Weather page.

Information and images of the flare activity is available from the Ionospheric Prediction Service (IPS) in Australia; especially the Solar page, that shows things like:
List of X-ray flares
Solar disk with flare image - Culgoora Observatory
Spectrograph 25-180MHz) - Learmonth Observatory
full disc image - Learmonth Observatory

Then, there is the comprhensive Space Weather page.

Information and images of the flare activity is available from the Ionospheric Prediction Service (IPS) in Australia; especially the Solar page, that shows things like:
List of X-ray flares
Solar disk with flare image - Culgoora Observatory
Spectrograph 25-180MHz) - Learmonth Observatory
full disc image - Learmonth Observatory

Then, there is the comprhensive Space Weather page.

True - a nice real time map of ionosphere reflection characteristics can be found here . The researchers themselves don't ever mention ionospheric bouncing.

On an unrelated not, the university I work at runs their own ionosonde. They used to have trouble with the station being vandalised until they put up a sign "Warning: this facility frequently bathed in high frequency electromagnetic radiation". The HF radiation in question was sunlight, but there hasn't been any problems since.

They seems very serious and it looks like a lot of thought has gone into it, judging by their publication list. For some retarded reason all the actual documents are in a restricted directory. I remember when academia was all about sharing ideas, now everyone's worried that someone else might beat them to the start up company.

Long distance vhf reception may be the result of ionospheric conditions (sporadic E skip, e.g.). A more common cause in my experience is tropospheric ducting ("trop"). Trop creates a waveguide in the atmosphere. It is often caused by a temperature inversion.
Although the speed of light is nearly as fast in air as it is in a vacuum, it does differ slightly. And it is lower in dense, cool air than in thin, warm air. In other words, the refractive index of cool air is higher that of warm air. The signals are bent back to earth when they hit a discontinuity in the refractive index caused by a layer of warm air overlaying a region of cool air. Inversion layers commonly form on cool, clear nights. So you will often hear anomalous FM reception in the morning -- distant stations heard between local stations, or even interfering with weak locals.
A Yahoo search on "temerature inversion radio propagation" will enlighten the curious - this is one result. Or run to the library and look in "The Radio Amateur's Handbook".