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spartan45

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spartan45 last won the day on February 6 2018

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About spartan45

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  1. Song, artist, album: 2,000 lockdown 2020 list in a forest of over 60 million songs (YT). Song Artist Album 10thAnniversary Tribute Melodysheep Symphony of Science YT 10538 Overture ELO ELO-Ultimate Collection CD2 (2001) 19 Paul Hardcastle 25 Years Of Number 1 Hits V.7 1999 Charli XCX &Troye S
  2. I like Google and Bing because they give you the number of results related to your question. Of the 3 you have listed I think DuckDuckGO is a good alternative. I was unfamiliar with Qwant and StartPage so I found your post interesting.
  3. I found a video clip recently posted on Utube interesting as it highlights the subject of the blackness of daytime space:- Astronaut Tim Peake’s ‘UFO Sighting’ in Space The Graham Norton Show : Astronaut Tim Peake “In the daytime in space, the space is black, the blackest black you could ever imagine and if see a light it’s another spacecraft coming towards you and we do when cargo vehicles arrive or crew hand-over to come over, you see these lights. On this one day I was looking out and I saw these 3 lights coming over flying in formation and I thought we’re not due a visiting spacecra
  4. Omnifarious, I like your post’s curiosity and determination to find answers, but you have brought up too many points for me to cope with so I thought I’d start with gravity. Gravity is intriguing; the best description of its nature I recently found is from the reference below the summary from that reference titled ‘Does the influence of gravity extend out forever?’ ‘In summary, the influence of gravity only extends to the edge of each gravity group. Beyond that, spacetime no longer behaves like gravity. It's not that the gravitational attraction of a star simply gets too weak to noti
  5. Apollo 14 (1971) Astronaut Alan Shepard describes what he sees after disembarking from the ‘Antares’ lunar module “-Look up in the black sky, there’s no reflection no diffusion and seeing another planet; planet Earth.” “It certainly is a stark place here; I think it’s made all the more stark by the sky being completely black.” REF: The TV documentary ‘Moon Shot’ from the Smithsonian Channel (2020). Apollo 16 (1972) Mission science experiments included The Far Ultraviolet Camera/Spectrograph which took pictures and spectra of astronomical objects in ultraviolet light. The Far Ultravio
  6. As others have already stated the visible universe is finite and just does not have enough stars to light up all of the sky. I did wonder if dust clouds between the stars might be absorbing a lot of the starlight so it wouldn't shine through to us. But apparently scientists tell us that the dust itself would absorb so much energy from the starlight that eventually it would glow as hot and bright as the stars themselves. So I guess dust the dust cloud idea is a non-starter. For a good comprehensive answer to this post’s question, I recommend the reference below. https://spacepla
  7. TomBooth; thank you for posting this interesting topic, very brave of you to challenge both the second law of thermodynamics heat flow statement: ‘Heat flows spontaneously from a substance at a higher temperature to a substance at a lower temperature and does not flow spontaneously in the reverse direction’ and also Carnot’s principle, (An alternative statement of the second law of thermodynamics), ‘No irreversible engine operating between two reservoirs at constant temperatures can have a greater efficiency than a reversible engine operating between the same temperatures. Furthermore, all rev
  8. I appreciate the Sun is a star. I must admit the question and wording ‘at what altitude can stars been seen in daylight?’ does seem a bit weird, but then so does the seemingly black void witnessed by astronauts and visual spectrum cameras above the Earth’s atmosphere from spacecraft and the International Space Station when the Sun is not blocked by the Earth. I am now curious how the Hubble Space Telescope overcomes the problem of seeing stars (other than the Sun which it must not look at because it is so bright it would destroy its sensitive instrumentation) in daylight, all I can think of is
  9. The existence of the Hubble Space Telescope is used as proof that stars can be seen in daylight above the atmosphere. The Hubble ST uses 3 spectral ranges, the near-UV (pivoted at 300nm), Visual light (380nm-740nm) and a limited infra-red (800nm-2500nm) capability. Here’s the thing; can the Hubble ST see stars in daylight using the normal human visual light spectral range (380nm-740nm), or does it have to resort to using the near-ultra violet spectral range ( pivoted at 300nm) to see stars in daylight? The only other optical space telescope I’m aware of is the Chang’e 3 Lunar-based ultraviol
  10. Special relativity means moving clocks run slow. The challenge is which clock is moving, so I hope this experiment (Keating) carried out in the 70’s using an aircraft heading W and then repeating the procedure heading E, while carrying atomic clocks synchronised with a master atomic clock at an observatory in the United States helps make sense of it: The clock on the W bound aircraft was travelling against the East bound spin of the Earth, (rather like a person walking the wrong way along a conveyor and not moving very much), while the master atomic clock in the United States was moved faste
  11. It is my understanding that an additional chip was fitted to the power steering, before leaving the factories, to detect if there was any movement of the steering wheel whilst the car was moving. If there was none, it would put the car into ‘clean’ mode to cheat the rolling road emission test, reverting back to ‘dirty’ mode when it detected steering wheel movement at the end of the test. I was amazed at how simple, but effective, this method of foiling the world’s diesel car emissions regulations appears to have been. We need to be watchful.
  12. Does anyone know if an individual is allowed to describe how the emissions test was cheated?
  13. Uranium is in short supply on the Moon. Ref: https://www.space.com/8644-moon-map-shows-uranium-short-supply.html Thorium (Th) is plentiful at Mare Imbrium on the near side and on the Moon where the lander Chang’e 3 and its rover, Yutu (Jade Rabbit) landed (44.12 deg N, 19.51 deg W) on 14 December 2013. Thorium is also plentiful in the south-pole Aitken Basin region on the far side of the Moon within which lies the Von Karman crater where the lander Chang’e 4 and its rover Yutu 2 (Jade Rabbit 2) landed (44.8 deg S, 175.9 deg E) on 3 January 2019. Ref: http://www.planetary.org/blogs/emily-lakdaw
  14. True. Thank you for correcting me; indeed, it was not astrology.
  15. Apologies for posting this after OceanBreeze has answered so well but I’d already written it and I need clarification on the Doppler Red shift equation. Special relativity means moving clocks run slow. Alice’s clock is moving in respect to Bob’s clock on Earth. The time dilation equation is: ∆t0 = ∆t√ 1 – v2/c2 ∆t0 = Alice’s spacecraft time interval (in light years for this example) ∆t = Bob’s Earth based time interval in light years = 3/0.6 = 5 v = spacecraft velocity 0.6c c = speed of light (2.99792458x108 m/s) (3.0x108) rounded (Cancels out in this example) ∆t0 = ∆t√1 –
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