Yötaivas teleskoopilla nähtynä Gamma Cygni kuva APOD NASA |
Arvon ursalaisemme oli jo hakenut kannettavan Schmidt-Cassegrain teleskooppinsa ja digitaaliset kameransa kajuutastaan ja asetteli niitä jalustoille Raja Laut kuunarimme arvopuiselle kannelle.
Hämärässäkin näimme hänen iloisen virnistyksensä "onpahan minulla jotain näytettävää kotiin palattuamme". Harmi, ettei GPS laite antaisi tarkkoja koordinaatteja sijaintikohdasta, mistä hänen kerrassaan ainutlaatuiset ja tähtitieteelle korvaamattoman arvokkaat kuvansa on otettu.
Sekstantti
C.Plath Professional Sextant (Hamburg) kuva Robert E. White Instruments Co. |
A sextant is an instrument used to measure the angle between any two visible objects. Its primary use is to determine the angle between a celestial object and the horizon which is known as the object's altitude. Making this measurement is known as sighting the object, shooting the object, or taking a sight and it is an essential part of celestial navigation. The angle, and the time when it was measured, can be used to calculate a position line on a nautical or aeronautical chart. Common uses of the sextant include sighting the sun at solar noon and sighting Polaris at night, to find one's latitude (in northern latitudes). Sighting the height of a landmark can give a measure of distance off and, held horizontally, a sextant can measure angles between objects for a position on a chart. A sextant can also be used to measure the lunar distance between the moon and another celestial object (e.g., star, planet) in order to determine Greenwich time which is important because it can then be used to determine the longitude.
wikipedia
Kuva Blue Water Supplies, Jersey |
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