Astrolabium Galileo GalileiAstrolabium Galileo Galilei

MR/Vers. 1.1

Creation and © 2003 by Marc Rogivue, Ulysse Nardin SAAll credits for the detailed explanations go to Dr. Marcus Hanke and his excellent book "The Trilogy of Time“

Java Script and Copyright of the “Electric Astrolabium” by Keith Powell

General Information

• First model of the Trilogy, First model of the Trilogy, presented in 1985presented in 1985

• First watch that sensitizes us for the things First watch that sensitizes us for the things happening in the skyhappening in the sky

• Perpetual Calendar has never to be adjustedPerpetual Calendar has never to be adjusted

• Automatic Movement UN-97 Automatic Movement UN-97 with 18K Rotor with 18K Rotor

• Quick Adjustment forwards and backwards over a Quick Adjustment forwards and backwards over a single crownsingle crown

The Small-Print: The first Astrolabes are known to have existed before 150 B.C. and served mainly two purposes; to observe and to display. Observation of the sky had mainly one purpose: to determine the correct date and time. Thanks to the watch movement inside the Ulysse Nardin Astrolabium, the purpose of observation has become obsolete and the main purpose today is to display the sky and its celestial bodies above us. It can also be used to predict astronomical events, for example the next eclipse of the sun or the time of sunset at any given date.It is the first watch that sensitizes us for the things happening in the sky and makes us become a better observer of nature and the stars above: The Dragon hand circles around the Ecliptic once every 18.611 years! Seconds, Minutes, Hours and even Dates are therefore becoming almost irrelevant. What counts is the movement of Earth, Sun, Moon and the Stars. Perpetual Calendar is exactly synchronized with the movement of the Earth around the Sun of 365 days, 5 hours, 48 minutes and 46 seconds. It therefore is the only Perpetual Calendar which has never to be adjusted!

The Elements of the Astrolabium:The Elements of the Astrolabium:

The Elements

• Sun-HandSun-Hand• Moon-HandMoon-Hand• Dragon-HandDragon-Hand

• EclipticEcliptic• Planisphere (Dial)Planisphere (Dial)• EquatorEquator• BezelBezel

• Hour and Minute-HandsHour and Minute-Hands

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The Small-Print: The Sun Hand makes one turn every 24 hours. The Moon Hand makes one turn every 24 hours and 49 minutes. The difference between Sun Hand and Moon Hand corresponds to the time the Moon takes to circle around the Earth once: 27 days, 7 hours, 43 minutes and 11.5 seconds. The Dragon Hand moves almost at the same speed as the Ecliptic, but it makes one extra turn every 18.611 years. It indicates solar or lunar eclipses, if it is aligned simultaneously with the sun and moon hands. Ecliptic represents the firmament and is divided into the 12 signs of Zodiac. It makes one turn every 23 hours, 56 minutes and 4.1 seconds (exact time that the earth needs for one rotation around its own axis). The Planisphere or Watch-Dial represents the Earth in a planispheric (flat) form. The horizon line separates the visible part of the sky (silver-colored upper part) from the invisible part of the firmament, hidden behind the earth. The Planisphere is calculated according to the latitude of the specific place. This example is 46 degrees North (Geneva and Chicago etc.). The Equator represents the calendar with monthly graduations. It makes one turn every 365 days, 5 hours, 48 minutes and 46 seconds (exact time that the earth needs for one rotation around the Sun). This takes into considerations all leap years of the Gregorian calendar and has never to be adjusted. The Bezel has a 12-hour graduation (Roman numerals) for the legal or normal time and a 24-hour graduation (Arabic numerals) for the solar or local time and all astronomical data. For better clarity, the 24-hour graduation has been omitted at the location of the Roman numerals.

Total of 21 Functions:Total of 21 Functions:

• Legal Time, Month, and Weekday• Solar Time• Sunrise & Sunset• Dusk & Dawn• Moonrise & MoonsetMoonrise & Moonset• Moon-PhaseMoon-Phase• Solar and Lunar Eclipse Solar and Lunar Eclipse • ZodiacZodiac• Position of Sun, Moon, and Stars Position of Sun, Moon, and Stars • Directions (Compass)Directions (Compass)• Tropics & SeasonsTropics & Seasons• Temporal Hours Temporal Hours

Electric AstrolabiumElectric Astrolabium

The Functions

Click here to see a fully working model of the Astrolabium Watch (Java Script and copyright 2003

by Keith Powell)

• Legal Time (or Normal Time)Legal Time (or Normal Time)

Time, Month, and Weekday

• WeekdayWeekday

• Month and DateMonth and Date

The Small-Print: Legal Time (or Normal Time) is shown by the hour and minute hands and the Roman numerals on the Bezel. On the example, it is 12:13 am or pm. Legal Time is the same for all cities within the same time zone, but might change during daylight saving times (ahead by one hour)

The Month is shown by the tip of the Sun hand on the Equator. The date can be estimated. The lines between the months indicate the first day of the month.

The Weekday is shown in the window near 6 o’clock.

• Solar Time (or Local Time)Solar Time (or Local Time)

Solar Time

The Small-Print: Solar Time (or Local Time) is shown by the tip of the sun hand and the Arabic figures on the 24-hour-scale on the Bezel (for better clarity, the 24-hour graduation has been omitted at the location of the Roman numerals). On the example, it is 18:50 (pm). The solar time will always show noon, when the Sun is in its Zenith at that particular place. The Solar Time depends therefore on the exact degree of longitude of a place. One degree of longitude corresponds to 4 minutes of time (24h / 360 = 4 mins). While the legal/normal time remains the same for all cities within a time-zone, the solar/local time changes from place to place, but is not affected by the daylight saving time.

Example: While Normal Time is 6pm for both Vienna and Amsterdam, Solar time is 6:08pm for Vienna and 5:20pm for Amsterdam.

• Sunrise

Sunrise & Sunset

The Small-Print: Sunrise: Sunrise occurs when the intersection of the Sun Hand crossing the outer rim of the Ecliptic reaches the left (Eastern) side of the Horizon Line.

• SunriseSunrise

Sunrise & Sunset

• Sunset:Sunset:• Example early Sunset in December Example early Sunset in December

(around 16:55 Solar-Time)(around 16:55 Solar-Time)• Late Sunset in June Late Sunset in June

(around 19:10 Solar-Time)(around 19:10 Solar-Time)

The Small-Print: Similarily, Sunset occurs when the intersection reaches the right (Western) side of the Horizon line. Since the Sun Hand moves at a slightly faster speed than the Ecliptic, the time varies daily. The example shows the difference between December, when the sun sets early (around 5pm) and June when the Sun sets late (around 7pm).

Dawn & Dusk

• Dawn & Dusk:Dawn & Dusk:• Long Dusk in December (about 2h)Long Dusk in December (about 2h)

• Short Dusk in June (about 1h) Short Dusk in June (about 1h)

The Small-Print: Dusk & Dawn: The time required by the intersection of the sun hand and the ecliptic to pass through the light grey zone is the twilight time. Dawn is given on the left (East), Dusk on the right (West). As soon as the intersection point leaves the twilight zone, it becomes completely dark. The example shows the difference between December (when the duration of dawn and dusk are long) and June (when the duration of dawn and dusk are short).

• Moonset in December around 17:00Moonset in December around 17:00

Moonrise & Moonset

The Small-Print: Moonrise and Moonset are shown when the Horizon line is passed by the intersection of the Moon Hand and the outer Rim of the Ecliptic (similar to Sunrise and Sunset)

Moon-Phase

• Waning MoonWaning Moon

The Small-Print: The Astrolabium does not only show the Moon-Phases, but also whether the Sun and/or Moon are currently visible on the sky. The Axis of the Hands can be understood as the location of the Earth.Since the Sun-Hand turns a little bit faster (one turn in 24h) than the Moon-Hand (one turn in 24h 49’), the Moon is waning whenever the Sun-Hand is behind the Moon-Hand.

Moon-Phase

• Waning MoonWaning Moon

• New MoonNew Moon

The Small-Print: If Sun and Moon are aligned and on the same side, it is New Moon.

Moon-Phase

• Waning MoonWaning Moon

• Waxing MoonWaxing Moon

• New MoonNew Moon

The Small-Print: Once the Sun has overtaken the Moon, it is waxing.

Moon-Phase

• Waning MoonWaning Moon

• Waxing MoonWaxing Moon

• New MoonNew Moon

• Full MoonFull MoonThe Small-Print: And if the Sun is opposite the Moon, it is Full Moon.

Solar & Lunar Eclipse

• Lunar Eclipse:Lunar Eclipse:Full Moon with Dragon Hand alignedFull Moon with Dragon Hand aligned

The Small-Print: The Dragon Hand moves slightly faster than the Eclipse and encircles it once every 18.611 years!The Dragon Hand symbolizes the angle in which the Sun – Earth – Moon must be in order that a Solar or Lunar eclipse occurs. If the Dragon Hand is aligned with Sun and Moon Hands during a Full Moon, a Lunar Eclipse will occur.It doesn’t matter whether the head or tail of the Dragon Hand is in coverage with the other two hands!

Solar & Lunar Eclipse

• Lunar Eclipse:Lunar Eclipse:Full Moon with Dragon Hand alignedFull Moon with Dragon Hand aligned

• Solar Eclipse:Solar Eclipse:New Moon with Dragon Hand alignedNew Moon with Dragon Hand aligned

The Small-Print: If the Dragon Hand is aligned with Sun and Moon Hands during a New Moon, a Solar Eclipse will occur. However, as seen on the graph, the shadow of the Moon on the Earth’s surface is much smaller than the shadow of the Erath on the Moon surface. Therefore a Solar Eclipse can only be seen from certain locations on the earth. If the Astrolabium indicates a Solar Eclipse, it therefore means, that the eclipse occurs somewhere on the world and not necessarily at your current location. It doesn’t matter whether the head or tail of the Dragon Hand is in coverage with the other two hands!

Zodiac:Zodiac:

AriesAries Mar 21Mar 21 – – Apr 19Apr 19 TaurusTaurus Apr 20 Apr 20 – – May 20 May 20 GeminiGemini May 21 May 21 – – Jun 21Jun 21 CancerCancer Jun 22 Jun 22 – – Jul 22Jul 22 LeoLeo Jul 23 Jul 23 – – Aug 22Aug 22 VirgoVirgo Aug 23 Aug 23 – – Sep 22Sep 22 LibraLibra Sep 23 Sep 23 – – Oct 23Oct 23 ScorpioScorpio Oct 24 Oct 24 – – Nov 21Nov 21 SagittariusSagittarius Nov 22 Nov 22 – – Dec 21Dec 21 CapricornsCapricorns Dec 22 Dec 22 – – Jan 19Jan 19 AquariusAquarius Jan 20 Jan 20 – – Feb 18Feb 18 PiscesPisces Feb 19 Feb 19 – – Mar 20Mar 20

Zodiac

The Small-Print: The current sign of the Zodiac is shown by the Sun Hand’s measure edge on the Ecliptic.

Positions of Sun, Moon, and Positions of Sun, Moon, and Stars are defined by Altitude Stars are defined by Altitude (above Horizon) and Azimuth(above Horizon) and Azimuth

Positions

Altitude (above Horizon):Altitude (above Horizon):

0° (Horizon itself)0° (Horizon itself)30° above Horizon30° above Horizon60° above Horizon60° above Horizon

Azimuth:Azimuth:

0° East0° East45° South - East45° South - East135° South - West135° South - West180° West180° West-135° North - West-135° North - West-45° North - East-45° North - East

90° above Horizon (Zenith)90° above Horizon (Zenith)

90° South90° South-90° North-90° North

Positions

• Position of Sun & Moon:Position of Sun & Moon:

• Position of Stars:Position of Stars:Directly given on the dialDirectly given on the dial

Example: 30° Altitude, 60° AzimuthExample: 30° Altitude, 60° AzimuthIntersection of Sun/Moon-Hand with EclipticIntersection of Sun/Moon-Hand with Ecliptic

Directions (Compass)

• During Day:During Day:

Direct Sun-Hand at Sun ->Direct Sun-Hand at Sun ->directions are given by the Bezeldirections are given by the BezelS

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Directions (Compass)

• At Night:At Night:

Direct Moon-Hand at the Moon ->Direct Moon-Hand at the Moon ->directions are given by the Bezeldirections are given by the BezelS

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Tropics & Seasons

The Planisphere shows:The Planisphere shows:

• Equator: Equinox; Equator: Equinox; Day and Night is equally longDay and Night is equally long

• Tropic of Cancer: Tropic of Cancer: highest position of Sun in Summer highest position of Sun in Summer (Summer Solstice)(Summer Solstice)

• Tropic of Capricorn: Tropic of Capricorn: lowest position of Sun in Winter lowest position of Sun in Winter (Winter Solstice)(Winter Solstice)

Tropics & Seasons

Examples:Examples:

• 12 Noon at Summer Solstice12 Noon at Summer Solstice

• 6pm at Summer Solstice6pm at Summer Solstice

• 12 Noon at Winter Solstice12 Noon at Winter Solstice

• 6pm at Winter Solstice6pm at Winter Solstice

The Small-Print: Summer Solstice (June 21) is the longest day in the Northern Hemisphere:12 Noon at Summer Solstice: Sun Hand and Ecliptic intersect with Tropic of Cancer. The Sun reaches its highest position (almost at Zenith, 90° above Horizon).6pm at Summer Solstice: The intersection of Sun Hand and Ecliptic is still in the light grey zone. It will take several hours before the Sun sets.

Winter Solstice (December 21) is the shortest day in the Northern Hemisphere:12 Noon at Winter Solstice: Sun Hand and Ecliptic intersect with Tropic of Capricorn. The Sun is at its lowest position (less than 30° above Horizon).6pm at Winter Solstice: The intersection of Sun Hand and Ecliptic is just passing the twilight zone. The Sun has set a few hours ago and Night has fallen.

Temporal Hours

Temporal Hours were used in the Medieval Age Temporal Hours were used in the Medieval Age when the Natural Night was divided into when the Natural Night was divided into 12 equal parts:12 equal parts:

Examples:Examples:• Short Temporal Hours (< 60’) in SummerShort Temporal Hours (< 60’) in Summer

• Long Temporal Hours (> 90’) in WinterLong Temporal Hours (> 90’) in Winter

• Temporal Hours = 60’ during Equinoxes Temporal Hours = 60’ during Equinoxes

The Small-Print: Temporal (or Apparent) Hours were used in the Medieval Age when clocks and watches were not widely available and when, for practical reasons, the Natural Night and the Natural Day were equally divided into 12 equal parts. Since a night in winter lasts much longer than a night in summer, the night hour in winter lasted longer than 60 minutes and shorter than 60 minutes in summer. Only during Equinox (in March and October), when day and night are equally long, the Temporal Hours last exactly 60 minutes.Temporal Hours were only abandoned after accurate mechanical clocks became commonly available.The Ulysse Nardin Astrolabium shows Temporal Hours only for the night, because the dial would otherwise be too cluttered.