Autor Wątek: Breakthrough Starshot - lecimy do gwiazd!  (Przeczytany 9471 razy)

0 użytkowników i 1 Gość przegląda ten wątek.

Offline Adam.Przybyla

  • Weteran
  • *****
  • Wiadomości: 3208
  • Realista do bólu;-)
Odp: Breakthrough Starshot - lecimy do gwiazd!
« Odpowiedź #90 dnia: Sierpień 03, 2017, 14:39 »
Bardziej by mnie intreresowalo odprowadzanie ciepla, bo chyba nie cale swiatelko  grzecznie zamieni sie w energie kinetyczna;-)
Z powazaniem
                                Adam Przybyla

Offline Borys

  • Weteran
  • *****
  • Wiadomości: 1997

Offline ekoplaneta

  • Weteran
  • *****
  • Wiadomości: 5656
  • One planet Once chance
Odp: Breakthrough Starshot - lecimy do gwiazd!
« Odpowiedź #92 dnia: Maj 10, 2018, 12:51 »
Polecam bardzo ciekawy artykuł przedstawiający trudności jakie musimy pokonać, żeby dolecieć miniżagielkami do Proximy i Alpha Centauri  :)

A tu najciekawsze wycinki z artykułu:

The sail for each StarChip is designed with a size of about 108 square feet (10 square meters) and a mass of less than 1 gram, meaning that it should be only about 100 atoms thick, according to the new study, which was published onlinetoday (May 7) in the journal Nature Materials. Creating a sail that's reflective, light and strong enough to make the journey to Alpha Centauri is a challenge that pushes the boundaries of existing science, the researchers noted.

The Starshot laser array will likely fire beams of specific wavelengths of near-infrared light to which Earth's atmosphere is transparent. Starshot sails need to not only reflect these wavelengths but at best absorb only a tiny amount of their energy, lest they heat up and get destroyed when hit with Starshot's extraordinarily intense lasers. Moreover, the sails must be light and thin enough to get pushed as strongly as possible by lasers.

In addition, much as how an ambulance siren sounds higher-pitched as the vehicle drives toward you and lower-pitched as it moves away, as the sails get farther away from the lasers, the light they receive will redden in a process called Doppler shift. Ideally, the sails should also reflect these redder wavelengths to get as much propulsion as possible from the laser beams, the researchers explained.

The scientists found that no known material possesses the perfect combination of properties to serve as Starshot sails. For instance, although metals such as gold and silver are excellent reflectors of near-infrared light, they would absorb too much energy from Starshot's lasers to survive.

Still, a number of materials have at least some of the required qualities, suggesting that they could serve as Starshot sails. These include crystalline silicon and molybdenum disulfide.
As far as finding a sail that reflects as much light as possible while staying low in mass, the scientists recommended sails with hexagonal lattices of holes to reduce their weight. The researchers also noted that controlling the microscopic structure of the sail — such as by using alternating layers of material, each only nanometers (billionths of a meter) thick — could boost its reflectivity and reduce its absorptivity.

Offline kanarkusmaximus

  • Administrator
  • *****
  • Wiadomości: 17938
  • Ja z tym nie mam nic wspólnego!
Odp: Breakthrough Starshot - lecimy do gwiazd!
« Odpowiedź #93 dnia: Maj 10, 2018, 13:30 »
Bardzo ciekawe!