MB Monday June 2 - Wild Turkey Sunset

by Glenn Hirsch


Wild turkeys and buzzing bugs announce the crescent Moon at Montebello, which hangs below Pollux and Castor creating an inverted isosceles triangle -- a giant symmetrical sign from the gods gradually sinking into the weeds. Tonight's Earthshine on the Moon is so bright it clearly illuminates Tycho quite clearly. And the seeing is remarkably steady. On the eastern limb below the Sea of Crises we can see the Crater Langrenus with its group of central peaks - one casts a pencil thin, razor sharp shadow for the crater's entire 120 km radius. James thinks it could be the shadow of a rille but Rukl doesn't show a rille in that crater - anyone know?

Io starts its transit of Jupiter at 910pm - we can actually see it since Jupiter now has a slight crescent shadow around the edge so Io stands out for a few minutes - then the transit of its shadow starts an hour later - and in only an hour more the shadow is midway across Jupiter's 143,000 km diameter. (The books say Io's orbital speed is 17.34 km/sec (62,640 km/hour) and that it completes a Jupiter orbit in only 1.8 Earth days.)

Procyon sets as Antares rises - flashing and blazing all its colors through the atmosphere. Castor splits easily. Which one is Castor again?... hmmmm... someone (Leonard ?) provides a useful mnemonic - "Pollux towards Procyon and Castor towards Capella".

More warm evening fun - binocular peeks at the Beehive, the Butterfly, the Jewel Box (at the bottom of Scorpius) and Omega Centauri. Couldn't find Centaurus A even though I found it last time - damn! Why DO we live so far North? Then Epsilon Bootes "Pulcherima" (Otto Struve's "most beautiful") gold and green 150 ly away only 3" apart. Can barely spit it. Mu Bootes 59 ly away a generous 109" apart

Finally M51 and NGC 4565 in Coma Berenices - like 132 million year old motes of house dust. Both galaxies are about the same size as the Milky Way - those smudges are what we would look like from there. I could make out M51's arms in James' 10" dobs and then .. in my 8" too? (The power of suggestion.)

At 1130pm, my evening ends all too soon as I have an hour drive back to San Francisco.... as I pack up there's an Iridium Flare and an ISS pass to the north. What a great night.