NavList:

   

Reply

To facilitate navigation, I have been hoping to use binoculars to find bright 
planets or stars before they are visible to the naked eye, but had not 
succeeded before Saturday, 6/29.  Frank Reed has commented on this, although 
most people caution that the moon is only visible when it’s higher than the 
sun.  A US Naval Observatory astronomer also mentioned electronic sextants 
that can track their vessel in real time during the day.

On Sat, I finally got around to putting an azimuth circle on a 5-inch 
Newtonian reflecting telescope purchased last year; a magnetic electronic 
level stuck to the top read off altitude.  Around 9 am, I immediately found 
Venus when it was higher than the Sun.  This prompted a trip to the copy 
store to make a less flimsy device than an azimuth circle Scotch tqped 
together from four pieces of paper. After fabrication was complete, Jupiter 
was visible in the evening after it cleared the clouds at about 10 degrees 
altitude; the Sun was setting then with an equal altitude.  I couldn’t see 
Mars or Mercury, which were setting behind the Sun.

I then looked for Jupiter with 7x50 binoculars while the Sun set but couldn’t 
find it until the sky noticeably darkened.  It finally became visible to the 
naked eye as twilight set inl. The 50-mm binocs were considerably smaller 
than my 130-mm telescope, explaining the difference, but I was disappointed.  
I had hoped to spot Jupiter or Venus with the binocs during the day.  Today 
at 2:30 EDT at 81*50’ West, the Sun is higher than Venus and neither it nor 
the nearby Moon are visible in the telescope.

So it seems it’s possible to use binocular or sextant telescopes to find 
objects invisible to the naked eye, as long as the object is higher than the 
Sun and bright.

Fred Hebard
mbiew@comcast.net


PS, The circle also helped me find the Ring Nebula, but I finally got there by 
star hopping, having already learned to recognize Lyra.  

   

Reply