06/13/11 – Ephemeris – The lunar crater Aristarchus

Monday, June 13th.  Today the sun will be up for 15 hours and 31 minutes, setting at 9:28.   The moon, 2 days before full, will set at 4:39 tomorrow morning.  Tomorrow the sun will rise at 5:56.

The moon tonight is bright.  The sunrise line or terminator on the moon is crossing the large gray plain called Oceanus Procellarum, the largest of the moon’s seas.  These seas were figments of the first telescopic observers imagination.  They are really huge impact basins into which interior lava flowed.  On the upper left edge of the moon near the terminator is a bright spot on the moon visible in binoculars.  In a telescope it is a crater called Aristarchus.  It is a fairly new crater, probably less than a billion years old.  As a rule the brighter the crater the newer it is.  Aristarchus is the brightest spot on the moon.  Over the years visual astronomers have seen hazes and bright spots from time to time in and near Aristarchus.

* Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

The moon with Aristarchus. Created with Virtual Moon Atlas.

 

06/15/11 – Ephemeris – The bright planets this week and a total lunar eclipse for Asia

Wednesday, June 15th.  Today the sun will be up for 15 hours and 32 minutes, setting at 9:29.   The moon, at full today, will rise at 9:35 this evening.  Tomorrow the sun will rise at 5:56.

It’s Wednesday and time again to take a look at the whereabouts of the bright planets.  The ringed planet Saturn will be visible in the south southwest as it gets dark.   It’s near the bright star Spica to its lower left.  Spica has a blue tinge, while Saturn is yellowish. It will set at 2:44 a.m.   Saturn is a wonderful sight is a telescope with its rings. Jupiter will rise at 3:19 a.m. in the east. Mars will rise at 4:19.  Venus now rises too close to sunrise to be seen in the twilight as is Mercury.  There will be a total lunar eclipse this afternoon our time, making it completely invisible from here.  However it will be perfectly visible from Asia where among others my grandson Chris is serving as a Marine.  I’ve emailed him the times which are also available on the Ephemeris Blog.

* Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

See http://eclipse.gsfc.nasa.gov/OH/OHfigures/OH2011-Fig03.pdf.

I’m giving the timings in both Universal Time (UT), also known as Greenwich Mean Time (GMT) or Zulu and Afghanistan Standard Time (AST) (UT+4.5 hours)

Event                         UT                  AST
Partial Eclipse Starts    15th 18:22            15th 22:52
Total Phase Starts        15th 19:22            15th 23:52
Total Phase Ends          15th 21:03            16th 01:33

Partial Eclipse Ends      15th 02:02            16th 02:32

The moon will enter the earth’s shadow from right to left.

During the total phase of the eclipse (we call it totality), the moon will probably appear red in color with gray near the edge of the earth’s shadow.

If you were on the moon, looking back at the earth at maximum eclipse the earth will appear as a red ring, the total of all the sunrises and sunsets around the earth.