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Yes - a tech should know better - but attaching a variable 30v PSU to electric toys designed for 5v turns out to be quite entertaining..

In addition to swansot's comment, putting a spy satellite that high would make it pretty useless as its image resolution would not be very good. Generally, they would be put into much lower polar orbits. So the Earth rotates under it, allowing it to observe pretty much any point on the surface over time. The particular orbit in the image is a Sun synchronous one. This means that as the satellite passes over a particular point of the Earth's surface, it is being lit the same by the Sun. This assures that differences in images between successive passes aren't due to different lighting angles from the Sun.

But that's not an excuse for succumbing to those instincts. One would think, as rational beings, we should be able to overcome them.

None. Geostationary orbits are equatorial

No one said that it should not be investigated. In fact, they are still underway. And many have been done in the past (I have seen studies going back to the 70s at least). None of them have found strong evidence for carcinogenic effects in humans so far. Required evidence is usually based on existing evidence levels, with clinical data (which is part of the approval process) having the highest weight. The actual evidence for cancer risk in humans is still low, and a bigger worry at this point is neurotoxicity during prolonged use. What ultimately has to be evaluated is the cost/benefit. Many drugs, including antibiotics, anti-cancer drugs etc. are highly toxic. The question therefore is whether there are groups which ultimately have more benefit than harm. Obviously, if there are alternatives that are lass harmful, they would be preferred. Some other antibiotics that can be used to treat certain conditions (such as Chron's disease) but depending on the person, the side effects can be more or less severe. There are basically no harmless drugs. Just various levels of harm. Again, the premise is not that we can only use drugs that have no risk of harming the patient. This is just not viable. It is about finding treatments for conditions that overall have the best risk/benefit ratio for a given condition and a given patient. So far, metronidazole makes the cut and with antibiotics efficacy waning, more toxic ones will be see increased use. If the intention was to create the perfect drug before use, well most of us would probably be dead before that happens. That all being said, I will agree that over prescription can be an issue. But that is not dealt with by kicking out drugs from the portfolio. Rather, we need better and faster diagnostics to ensure that we only prescribe antibiotics that are needed. With cancer risk, conclusive evidence under therapeutic limits is very difficult. It is looking for rare cases among rare cases requiring huge cohorts to see an effect. As such having enough statistical power to show no effect is going to be exceedingly difficult. I.e. the rate of stomach cancer is maybe around 10 per 100,000 persons. So even if you enroll 10,000 control cases and 10,000 folks taking the drug, you may have maybe one case, which could be purely stochastic. Even worse, you would need to track them for years which would make it a tremendously expensive study. So realistically you would need many individual studies and try to look at a meta-analysis, or more likely have retroactive surveys. The issue with the latter is that there are a lot of confounding factors beyond the drug under consideration that may affect cancer risk. So even those might not reach enough folks to figure things out. That all being said, some of the earlier studies in the 80s tracked over 700 patients for close to 10 years, seeing no effects for patients treated for trichomoniasis for any types of cancers (if adjusted for smoking). Another study was retrospective and looked at matched patient data (i.e. similar groups but one with and another without treatment) for about 10-12 years found no effects for short-term exposure, either. Since then, there have been follow-ups using similar designs but no smoking gun. That being said, other commonly used antibiotics are starting now also to be suspected to potentially be associated with cancers during long-term treatment. For example one retroactive comparison between clarithromycin compared to metronidazole (there was no untreated patient cohort) showed that clarithromycin had a higher overall death and cancer risk than metronidazole after follow-up. (And interestingly clarithromycin is also under discussion to be used as a potential repurposed drug for cancer treatment at some point...). Also, it is necessary to look at risk in context of overall risk we are willing to commit. For example, certain diets are associated with cancer, and we are likely to eat more of it and for longer than an antibiotics course. In summary, folks look at the available set of info to assess risk/benefit. Sometimes the assessment is wrong (thalidomide being one of the famous examples), but it always is based on need and empirical evidence. Otherwise, options would be really, really limited.

This question is the same as to ask, what is the speed of the Moon's shadow on the Earth's surface. This has been discussed here: https://www.scienceforums.net/topic/131698-moon-shadow/ The simple case answer, on the equator, with a back-of-the-envelope calculation was: (https://www.scienceforums.net/topic/131698-moon-shadow/?do=findComment&comment=1240426) The Earth spins from West to East making a full circle in 1 day. The Moon rotates around the Earth from West to East making a full circle in 30 days. OTOH, the radius of the Moon's circle is about 300000 km while the Earth's radius is about 6000 km. This makes the Moon's circle 50 times longer. The Moon makes 50 times longer way in 30 times longer time, i.e., it moves from West to East 50/30 times faster than the Earth surface. Thus, its shadow should move to the East faster than the Earth surface does, hence its shadow on the Earth surface moves to the East.