It is not red.
Apparent the species can range in color from a pale gold, to a dark, almost black, red. I have seen this species a couple times now. The previous specimens I had found were the characteristic red, seeing this gold nudi I thought I had found something new to me.
But it is a red dendrodoris. This is a well known, but undescribed species that is found on island reefs. This fellow was in a cave at Horseshoe, depth about 35ft.
An undescribed species of Dendrodoris, depth 35ft on the Kohala Coast
One drawback to the many iPhone astronomy apps is the lack of large databases. To an advanced amateur such as myself, the lack of detailed databases is a distinct negative in these programs. I venture way beyond the Messier catalog, or even the NGC on a regular basis. I understand the price to be paid in speed and memory required to support larger databases, but I would like to have the option.
Comet C/2007 N3 Lulin on the evening of 26 Feb 2009, a stack of 10 x 4 min exposures, Canon 20Da and TeleVue 76mm APO
The programs I have seen also lack the ability to display comets or asteroids. This last issue has become a problem lately, as we have several nice comets available in the sky for observing. A quick way to look up the current position for the object is essential for comets and asteroids if you wish to observe them. Last night’s coordinates will have you looking at an empty starfield tonight.
There is one decent answer for comets… I found a very nice app for comet ephemerides published by Keith Yohn. Called simply Comet, this free program downloads the latest ephemeris data from the Minor Planet Center and displays the current and future coordinates for each comet. Just what I needed!
There are no charts, the data is simply displayed in table form. Every observable comet is displayed and can be search for using a simple set of filters.
When attempting to observe comet C/2009 P1 Gerradd a few times recently. I have found the coordinates to be quite accurate. The comet was in the sky, right where the app showed it would be. Nothing like a real world test.