Solar Eclipse: Star Charts


I am interested in reproducing the “Eddington” Experiment, which demonstrated The gravitational shift of star positions.  Now, I have not been practising, so the likelihood of my success is very low.  But I still intend to try, to see what information I can obtain.

First, I show a roughly 70 degree wide star field.  It is of interest because it shows Venus is within 35 degrees, roughly west, of the sun.

2017 Eclipse Stars 70 deg Field

2017 Eclipse Stars 70 deg Field

It may be a challenge to try to see Venus during the partial phase of the eclipse.  I suggest doing from within a building’s shadow, so you are not tempted to look at the Sun.

2017 Eclipse Stars 20 deg Field

2017 Eclipse Stars 20 deg Field

The above chart shows Mercury is within about 10 degrees, east of the Sun.  And Mars is a similat distance to the west.  I don’t suggest looking for these during the partial eclipse,  but they should be visible in the cloud-free skies [eternal unwarranted optimism] of the total eclipse.

2017 Eclipse Stars 10 deg Field

2017 Eclipse Stars 10 deg Field

This chart might help identify stars within 5 degrees of the sun, potentially seen during the total eclipse.

2017 Eclipse Stars 5 deg Field

2017 Eclipse Stars 5 deg Field

Finally, this chart shows stars within a few degrees of the sun, and are candidates to observe the gravitational shift.  Regulus should be visible, and the numbered Leo stars may show up in photographs to give some context.   The simply numbered stars indicate their magnitude.  There are a few very near the sun that are 7th magnitude.  Two of these are very close.  However, these close stars may be difficult to pick out of the Sun’s Corona.

I expect the two big challenges will be to pick stars out from the Corona, which limits useful exposure times, and getting sharp enough images to identify star positions to an arc second or better.

These charts were generated from Elwood Downey’s XEphem program.  It is available from Clear Sky Institute for a modest sum.

These charts were generated for Greenville, SC.  Your mileage may vary.

Update: forgot to take the solar filter off the telescope during totality. Oh well, there is 2024. I saw Venus during totality, but not Mercury and Mars. The sky was not as dark as I expected.  I could see light from both the North and South horizons.  The Corona was larger than I expected.

Created using XEphem

&copy 2017, David B Snyder

Advertisements