'at's a better size.
Actually Mark the size you have uploaded is great for showing the effect of automatic compression. If you click repeatedly on the 'Fit Image to Window" Icon, you will see the loss in resolution in just autoresizing just that small amount. Well it does on my laptop screen. There is a significant loss of resolution in downsizing just a small bit.,
When uploading its so easy and important for people to manage their own image compression rather than let software guess the right amount. Particularly for astroimages when resolution remains paramount throughout the whole process. PS also has a great Save For Web and Devices option as well that gives even greater control.