In the late 1950's and 1960's, the unusual orbital characteristics of Phobos has led to speculation that it might be hollow.
Around 1958, Russian astrophysicist Iosif Shklovsky Samuilovich, the study of the secular acceleration of Phobos' orbital motion, proposed a "thin sheet metal" of Phobos, the proposals that have led to speculation that Phobos was an artificial origin. [33] Shklovsky based his analysis on estimated the density of the upper atmosphere of Mars, and concludes that for weak braking effect to be able to account for the secular acceleration, Phobos should be a very easy calculation yielded a hollow iron sphere 16 km across but less than 6 cm. [33] [34] In February 1960 letter to the journal Astronautics, [35] S. Fred Singer, a science adviser to U.S. President Dwight D. Eisenhower, came out in support of the theory of Shklovskii, stating:
[Phobos'] purpose may be to sweep up radiation in Mars' atmosphere, so the Martians could safely operate around the world.
My conclusion there is, and here I am back Shklov that if the satellite is indeed spiraling inward as derived from astronomical observations, that there is little alternative to the hypothesis that it is hollow, and therefore made a martian. Big 'if' lies in the astronomical observations, they may well be a mistake. Because they are based on several independent sets of measurements of decades, except for different observers with different instruments, systematic errors may affect them. [35]
Subsequently, however, the existence of acceleration, which led to the claims was called into question [36] and accurate measurements of the orbit can be 1969 found that the difference does not exist. [37] The singer's criticism was justified, when the early studies were later found to have used to overestimate the importance of 5 cm / year to calculate the altitude loss, which was later revised to 1.8 cm / year. [38] The secular acceleration is attributed to tidal effects, which were not considered in previous studies. The density of Phobos has directly measured the ship will be 1,887 g / cm ł [4], which is contrary to the hollow shell. In addition, images obtained with the probe Viking in 1970 clearly showed a natural object, not an artificial one, and "hollow" Phobos "Speculation had been relegated to the status of historical curiosity.
kolovoz, 2009 | ||||||
P | U | S | Č | P | S | N |
1 | 2 | |||||
3 | 4 | 5 | 6 | 7 | 8 | 9 |
10 | 11 | 12 | 13 | 14 | 15 | 16 |
17 | 18 | 19 | 20 | 21 | 22 | 23 |
24 | 25 | 26 | 27 | 28 | 29 | 30 |
31 |
Dnevnik.hr
Gol.hr
Zadovoljna.hr
Novaplus.hr
NovaTV.hr
DomaTV.hr
Mojamini.tv
All about Phobos
Dnevnik.hr
Video news portal Nove TV
Blog.hr
Blog servis
Forum.hr
Monitor.hr
http://bbop.blog.hr
http://lollita.blog.hr
http://tkojeubiomickeymousea.blog.hr
http://malasoba.blog.hr