The Motions of HighLatitude Hydrogen Clouds
Abstract
We have obtained the solar motion with respect to 268 wellresolved (in velocity) 21cm hydrogen clouds with galactic latitudes numerically greater than 20 and declinations greater than 400. The result is a velocity of 21?2 + 0?9 km toward t = 52?5 + 2?9, b = +210.3 + 206 where the uncertainties are standard errors. The mean distance times the galacticrotation constant is 6.8 + 2.1 km sec', and the apparent longitude of the center of rotation is 346?5 + 4?0. The residual radial velocities are well fitted by an exponential distribution function of the form P(v) = (2 1 exp ( IvI/ where the maximumlikelihood principle gives 5.0 km for ,;. The average distance of hydrogen clouds in the latitude range does not follow a cosecant law, but rather is approximately constant.
 Publication:

The Astrophysical Journal
 Pub Date:
 January 1970
 DOI:
 10.1086/150312
 Bibcode:
 1970ApJ...159..319M