WatchDesign Astro II Constellation Watch - Astronomy/Astronomical Night Sky View with Rotating Planisphere map Complication

Is it the most practical timepiece ever? No. But the aesthetic is immaculate, and lets be honest, I bought this solely for the look, and on that front it absolutely delivers. The watch part is great, and although the planisphere is small which makes it difficult to read, in my opinion this is more of a statement piece than a functional one. You also have to manually operate the planisphere with one of the dials; it’s not automatic or integrated into the clockwork. I get lots of compliments about it, but do frequently end up having to explain to people what a planisphere is and how it works. When I actually need to use a planisphere to identify constellations it’s much more convenient to just use my phone, but I love wearing this watch anyway - it’s so unique and interesting and looks gorgeous on my wrist.

Re: Watchdesign ASTRO II - CONSTELLATION WATCHThis watch provides an elegant display of both solar and sidereal time. The solar time (the usual 12 hour AM/PM dial) is indicated automatically (with the precision of a quartz watch); however, the sidereal (star) time is approximated manually and for the Northern hemisphere only.The description is deceptively simple and the manual requires familiarity with basic astronomical concepts. Even with a magnifying glass, the cluttered miniature planisphere (the oval-shaped map of the night sky displayed in the lower half of the watch) is impossible to read and decipher unless the user is already familiar with the celestial coordinates of the major constellations (which defeats the purpose of using a planisphere). Also, the user would need to know where Polaris (the North Pole star) is located to make this watch (or any planisphere) useful in mapping the sky.In my experience, the most efficient use of this watch would be to approximate the local sidereal time (LST) by manually setting the month, day and (24 hr) time as described in the manual (aligning the constellation dial). The LST is approximated by the vertical North-South axis (the Meridian) running thru the center of the watch; the hour indicated at the lowest point in the outer (24-hr) ring is the approximate LST.For the Northern stargazer looking South, the projection of the Meridian, from Polaris thru the Zenith (the highest point above), divides the sky into a left (East) and right (West) side, corresponding to the stars and constellations displayed in the planisphere.The red circle in the planisphere represents the Celestial Equator, an extension of the Earth's Equator. Stars are located with positive (northern) or negative (southern) declinations from this Celestial Equator.Planet Earth rotates around its axis counter-clockwise, but this rotation is perceived as a clockwise motion of the stars in the night sky, as viewed from the North Pole (looking South). The Orion's Belt in the Northern Winter sky (declination = 0) is an easy way to identify the location of this equatorial circle for each latitude.The Vernal Point (VP) is a relatively fixed point in the sky used as an astronomical point of reference. The LST measures the time (hh:mm:ss) it takes for the VP to return to the same position each sidereal day. Because the Earth also moves in its orbit around the Sun, the sidereal day is 4 minutes shorter than the solar day. Therefore, the VP shifts 4 minutes from the Meridian each day. For instance, the LST at noon (Sun at the Meridian) would be 00:00:00 on March 20 and 01:00:00 fifteen days after (4 min x 15 days = 60 min = 1 hour angle).Likewise, any star can be located by its orthogonal (right) projection along the equatorial circle in reference to the VP. The angular separation from the VP is measured eastwardly in terms of hh:mm:ss units of "Right Ascension" (RA). One hour of RA = 15 degrees of separation, so that 15x24 complete a full circle of 360 degrees. For instance, the Orion constellation is located between the 5th and 6th hour of RA (corresponding to 75 to 90 degrees east from the VP).The brightest star in the night sky, Sirius (located at 06:45 of RA and some 17 degrees south of the Celestial Equator), would be found moving from the southeastern to the southwestern quadrants of the night sky throughout the Winter in the Northern hemisphere. This is so because at 9:00 PM (21 hour Solar Standard Time) the LST would range from 5:00 in January to 9:00 in March. January thru March would also be an ideal time to locate Orion's Belt in Celestial Equator.In summary, the Celestial Equator and the Meridian (LST) divide the visible night sky into four quadrants to assist the stargazer in finding stars and constellations. This watch is very useful for this purpose. However, its usefulness is quite limited to locate stars and constellations in its cluttered planisphere. Restricting the displayed star map to major visible stars and constellations would greatly improve its general usefulness. ###PS (2021.04.10 update): Overall rating increased to 4.5. The JARLINK 30X 60X Illuminated Jewelers Eye Loupe Magnifier, Foldable Jewelry Magnifier with Bright LED Light for Gems, Jewelry, Coins, Stamps, etchttps://www.amazon.com/gp/product/B078N34WZR/ref=ppx_yo_dt_b_asin_title_o00_s00solved the magnifying problem. Highly recommended to enjoy this watch. -JB

I really want to give this a good rating because it's so beautiful but I am pretty frustrated with it actually. The instructions that come with it SUCK! I wish I had known that before I spent so much money because I really want to use its functions but I don't know how and it seems really hard to get any info from the seller. For such a nice watch it should have a better manual.

Because I've been using my telescope more frequently lately, I've gotten more interested in the local sidereal time, which tells us what part of the sky will be on our southern meridian (due south from you), especially the sidereal time when it gets dark, i.e. what the Right Ascension will be due south at that time. Since I live at 50 degrees North, it gets dark at 10 or 11 pm in the summer and at 4 or 5 pm in the winter, I need an extra measure of flexibility.This watch is a manual analog computer that provides a fairly accurate estimate of the corresponding sidereal time when the user uses the planisphere dial to align a time of interest with a given date.The watch has a normal clockwork that I keep on local standard time year round, and whose movement establishes the 12 o'clock and 6 o'clock positions--the hours are not marked but your prior experience with clock faces will help you make out the current time. A 12-month calendar is inscribed on the face as well with March 21 at the 12 o'clock position and September 21 at the six o'clock position.An outline of an astronomer's horizon in white overlays the watch face, so that the south meridian runs from the 12 o'clock position to the six o'clock position. Refer to that outline to coordinate your view of the sky with the local time.The idea is to find your current local (standard) time on the adjustable 24-hour planisphere dial and adjust it until the local time aligns with today's date on the inscribed calendar. When that's done, find the 6 o'clock/south position of the watch and read the planisphere dial at that position to get a very good estimate of the corresponding local sidereal time--i.e. what stars are up at that time.So if I know when darkness is expected today, I can move that hour on the 24-hour dial to today's date on the calendar and the astronomer's horizon will tell me what parts of the sky will be available that evening.These days, I could consult many apps for this, but cloud cover comes and goes, and this watch makes it easy to do a quick check if I notice a break in the weather coming up.Now that I've gotten used to this small analog computer, I've begun to use it to track/model the progress of the sun's RA over the course of a year by aligning the 12h position on the adjustable dial with a given day's date. I've also begun to pay attention the RA positions of the planets and of other objects I might want to try to observe.Pluto just came out of retrograde (during which its RA decreases night by night heading west) and Saturn will come out of retrograde in a week to two. Jupiter and Mars are currently both in retrograde, too, but you do need other apps to keep track of those. It doesn't matter really but it is as interesting astronomy and the Asto II watch drew my attention to all of this.I don't really use the attactive planisphere map except for its ecliptic and celestial equator lines.So I'm getting a lot of use out of this watch and I can recommend it to people interested in amateur astronomy.

I returned this watch because it was too hard to read. I never was given a refund. Returned thru UPS.

Bought this for my kid. Hard to figure it out, and very small font on watch. Difficult to read hands. Pass.