PDF Slides - UMBC
PDF Slides - UMBC
PDF Slides - UMBC
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
… Altair (α~20h, δ=+8 O ) from <strong>UMBC</strong> (lat ϕ~40 O ) today/tonight<br />
Source will rise or set when cosh = − tanδ tanφ ~ - 0.12<br />
( )<br />
h = cos −1 − 0.12<br />
so Sidereal time of rise and set given by<br />
ie Θ r/s ~ 26.5hr or ~13.5 hr<br />
ie.<br />
but we also know that currently (~11:30 EDT)<br />
Θ ~ 9.5hr<br />
~ +/- 97.4 O<br />
which is equivalent to ~ +/- 6.5 hr<br />
Θ = h + α<br />
..hence Altair will cross local horizon<br />
~4.0 hr and ~17 hr in the future<br />
ie at ~3:30pm (EDT) this afternoon [when actually still light of course]<br />
& ~4:30am (EDT) tomorrow morning<br />
Also Note: ~10pm culmination [found previously]<br />
half way between these times (of course!)<br />
Ian M. George PHYS 304 (2011 Fall) Meeting 04
Change language