Horoscho Chart User Manual (Overview)

Horoscho Chart is an astrology app that calculates and displays various horoscopes (charts) from birth data. It uses the astronomical computation library Skyfield together with high-precision ephemeris data, and lets you handle everything from a natal chart to bi-wheels, tri-wheels, and 5-wheels, as well as timing charts and tables, all within a single app.

1. Introduction

What This App Can Do

• Enter and save birth data (locations automatically resolve to latitude/longitude via place-name search)
• Display Natal / Bi-Wheel / Tri-Wheel / 5-Wheel charts
• Compare charts using Transit, Progression, Solar Arc, Synastry, and more
• Timing tables, declination graphs, midpoints/harmonics, and analysis graphs
• Monthly ephemeris, void calendar, and LIFELOG (client records and event logging)

Overall Map

You can navigate between screens using the icons at the top of the header. From left to right they are arranged as: Home → each chart type (Single / Bi-Wheel / Tri-Wheel / 5-Wheel) → analysis tools (Analysis Graph / MP-HM / Declination) → calendar tools (Ephemeris / Timing Table / Void Calendar) → LIFELOG. Hover over an icon to see its name.

2. Basic Workflow

When using the app for the first time, follow these three steps.

Step 1: Enter the Data

On the Home (input) screen, enter the name, date of birth, time of birth, and place of birth. When you type a place name, suggestions will appear; selecting one automatically fills in the latitude, longitude, and time zone. Entered data can be saved and recalled later.

Step 2: Display the Chart

Once the data is entered, select the icon for the chart you want to view (for example, Single Chart). The wheel (circular diagram) will be displayed along with a list of planetary positions and aspects.

Step 3: Look Up the Meaning

Click on a placement you are curious about to see the meaning of the planet, sign, house, or aspect. If you are unfamiliar with a term, refer to the Glossary of Terms at the bottom of this page.

3. Common Operations (Common to All Screens)

Switching Language

You can switch the display language using the language dropdown in the top right of the screen. Seven languages are supported: Japanese, English, Spanish, Italian, Portuguese, French, and German. The selected language is remembered and carried over to other screens.

Switching Theme (Dark / Light)

Use 🌙 (dark) and 🌤 (light) in the top right to switch the color scheme. The accent color can be changed on the “Settings” screen.

Copy / PDF Export

Many screens include a button to copy the displayed content to the clipboard, or a button to save it as a PDF. Use these when you want to paste the results into another app, or to print or save them.

Header Navigation (Reading the Icons)

The icons lined up at the top are entry points to each screen. The icon for the screen currently open is shown in a highlighted color. The divider lines (｜) mark group boundaries, separating “Charts,” “Analysis,” “Calendar,” and “LIFELOG” from left to right. The ? icon at the far right opens the help for that screen.

Settings (⚙)

From ⚙ Settings in the top right, you can change the time zone, house system, displayed celestial bodies, node/Lilith type, accent color, and more, all in one place.

4. Input Screen (Birth Data)

The Home (input) screen is where you register the data that forms the basis of a chart. The form is on the left and the map is on the right.

Three Tabs

• Birth Data … Enter the person’s date, time, and place of birth (this is the main tab).
• Current Data … Enter data for “now” or any other point in time. Used as the reference for comparisons (such as transits).
• Place Input … Used when you want to search for or specify only a location.

Entering Birth Data

Enter the name and select the year, month, day, hour, and minute. If the birth time is unknown, check Birth time unknown. For the place, typing a place name will bring up suggestions; selecting one automatically fills in the latitude, longitude, and time zone. You can also specify a location by clicking on the map on the right.

Rodden Rating (Data Reliability)

This is an indicator of how reliable the birth time is. You can choose from AA (most reliable, e.g. from a birth certificate) through A・B・C・DD・X. If unsure, you may leave it blank. The Data Reliability button explains the meaning of each rating.

Save and Copy

Once entered, press Save to register it as a client record, which can be recalled later. Use 📋 Copy chart only to copy the chart image, and 📄 Chart + basic data PDF to save it as a PDF. 📍 Use current location lets you pull in your current location.

5. Natal (Single Chart)

This screen displays a single person’s birth chart. The wheel (circular diagram) is on the left, the data table in the center, and the settings panel on the right.

Six Tabs

• Basic … A list of celestial body positions (sign, degree, house, declination, dodecatemory). This is the tab that opens first.
• Aspects … A list of angular relationships between planets.
• House Order … Check placements arranged in order of the 12 houses.
• Sabian … The Sabian symbol for each celestial body.
• HM … Toggle display of harmonics (HM1–HM12).
• Settings … Customize the display on this screen (details below).

What You Can Do in the Settings Tab

There are three groups: “Chart Type,” “Display / Houses,” and “Aspects.” You can choose the house system from 10 types including Placidus, Koch, Whole Sign, Equal, and Solar Sign. The celestial bodies displayed, the types of aspects, and the orb (allowed degree tolerance) can also be adjusted here.

Reading the Wheel

Celestial body symbols are placed within the circle, and lines connecting planets represent aspects. Click on a placement you are curious about to see its meaning. You can export using 📋 Copy chart only or 📄 Chart + basic data PDF.

6. Bi-Wheel Chart

This screen overlays two charts as an inner and outer wheel for comparison. It is used to view transits, progressions, synastry, and more.

Choosing the Inner and Outer Wheels

First, use the two dropdowns to decide what to overlay.

• Inner wheel … Natal chart or Midpoint.
• Outer wheel … Choose from Transit / Progression / Solar Arc / Solar Return / Lunar Return / Synastry (another person).

When “Synastry (another person)” is selected, specify the other person’s data using 👤 Person B Settings in the top right. Use 📅 Date/Time Settings to change the reference date and time for the outer wheel.

Role of Each Tab

• Basic … A comparison table listing the inner and outer wheel celestial bodies side by side. Dispositors (rulership flow) are also shown below.
• Synastry … Check the favorable/unfavorable nature of aspects between the two people.
• MP … View midpoints by category: “Life’s Center / Love / Success / Difficulty / Spirit / Society.”
• Future Forecast … Calculates the progression of transits/progressions by specifying a reference date, direction (future/past), and period (10 days to 1 year).
• Future 2-SA … Displays the progression using Solar Arc over 5 years, 10 years, 20 years, or an entire lifetime.

Lower-Left Controls

Here you can quickly switch between Nodes (True/Mean), Lilith (Mean/True/Natural), aspect display (inner wheel/cross/outer wheel/none), the orb slider, and house system.

7. Tri-Wheel / 5-Wheel Chart

This screen extends the bi-wheel further, allowing you to overlay multiple points in time or multiple people at once. The operations are nearly identical to the bi-wheel, and you move through the target date/time using the date/time stepper (increment/decrement buttons for year/month/day/hour/minute).

What Each Ring Represents

• Tri-Wheel … Inner wheel = natal chart, middle wheel = progression, outer wheel = transit.
• 5-Wheel … From the outside in: T (transit) / P2 (Person B’s progression) / N2 (Person B’s natal chart) / P1 (Person A’s progression) / N1 (Person A’s natal chart). Lets you compare two people’s natal charts and progressions all at once.

Tabs

Both use the same tab structure: “Settings / Basic / Aspects / Houses / Sabian.” Use Current Time to set the date/time to now, and export with 📋 Copy chart only or 📄 Chart + basic data PDF.

8. Timing Table

This screen lists astronomical events occurring within a specified period in table form.

How to Operate

Select the year, month, and period (1 / 3 / 6 / 12 months) and time zone, then press Display to show the table. You can narrow down the event types you want to see (moon phase, ingress, retrograde, void, aspect, solar term, solar/lunar eclipse) using checkboxes.

Reading the Table and Linking to Charts

The table shows “Date / Time / Type / Details,” color-coded by type. Click any row to display the chart for that moment. Use Send to (Single / Bi-Wheel / Tri-Wheel / 5-Wheel) to choose which screen opens when you click. Use CSV to export the table.

9. Declination Graph

This screen shows changes in a celestial body’s “declination” (its north-south deviation from the celestial equator) as a line graph.

How to Operate

Specify the display mode (transit / progression & SA), start date, and period, then press Show Graph. Export with 📄 Export PDF or 📋 Copy table.

Toggles and Terms

• OOB background color … Colors the range where declination exceeds ±23°26′, known as “out of bounds.”
• ± centered on 0° … Switches between viewing declination as signed north/south (±) or as an absolute value.
• P (Parallel) / CP (Contra-Parallel) … Relationships where declinations are equal, or symmetric across north/south. Check the corresponding times in the list on the right.

10. MP/HM (Midpoints / Harmonics)

This screen displays midpoints (MP) and harmonics (HM) as line graphs.

Two Modes

• MP (Midpoint) … View the relationship of other celestial bodies relative to the midpoint of two bodies.
• HM (Harmonics) … Fold celestial body positions back using a selected harmonic number to visualize fine angular relationships.

How to Operate

Switch modes with the purple MP / HM button; when in HM mode, select the harmonic number. Specify the start date and period to display the graph, and use the legend on the left to check which celestial bodies to show. Hover over the graph for details.

11. Analysis Graph

This screen analyzes the progression of transits and similar techniques using graphs.

How to Operate

Choose the display mode (transit / progression / solar arc), the period, and the position of the reference point (past / present / future), then press Show Graph. Use the Show minor aspects toggle to add or remove finer aspects, and adjust which celestial bodies are on/off using the legend on the right. Use Change Data to change the natal chart or location.

12. Monthly Ephemeris / Void Calendar

Monthly Graphic Ephemeris

Enter the year and month and press Calculate to display that month’s celestial movements graphically. You can scroll horizontally to view the entire chart, and the legend shows each celestial body’s color and symbol.

Void Calendar (Monthly Calendar)

Select the year, month, and time zone and press Display to show a one-month calendar table. Use checkboxes to show or hide layers for Void / Moon Phase / Ingress / Retrograde / Aspects. Use 🖨 PDF (A4) to print, and 📅 ICS to export for use in calendar apps.

13. LIFELOG

This screen records and manages people (client records) and their life events. It links with natal charts and the timing table.

List of Client Records

Use ＋ Create New Record to register birth data. You can narrow results using category tabs and organize them by sort order (last updated / by name / by birth date). Click a card to open its details.

Record Details and Events

In the details view, you can change the icon, check gender and birth information, and use View Natal Chart to jump to the chart. Use ＋ Create New Event to add an event to the timing table; each event can include a partner, a URL link, and free-text notes. Clicking a date displays the chart for that moment.

14. Settings

This screen sets the default display and calculation options for the entire app in one place. After making changes, press Save at the bottom to apply them across all screens. Use Reset to Default to restore the initial state.

Items You Can Change

• Display Language … Japanese, English, Spanish, Italian, Portuguese, French, German.
• Default Time Zone … The default value used when creating a new chart (e.g. +09:00 JST).
• Celestial Bodies Used … The 10 planets, Nodes (North Node type) and Lilith (type), sensitive points (ASC, MC, Vertex), asteroids, Chiron, and more.
• House System … Placidus, Koch, Whole Sign, and others.
• Degree Display … Degrees/minutes/seconds (°′″) or decimal (°).
• Aspects … Major only / all types, handling of out-of-sign aspects, applying/separating, and the reference point.
• Color Mode … Dark / Light.
• Accent Color … Red (default), orange, pink, green, purple, or a custom color.

15. Other (Position List / Verification)

The Position List (positions) page lets you check the positions of celestial bodies together in table form. The Verify page is a development/verification page used to check whether calculation results match other reference sources (such as astro.com). It is not used in ordinary readings, but is useful when you want to check the figures in detail.

Appendix: Glossary of Terms

Here is a short summary of astrological terms and concepts. Please refer to this alongside the operating instructions for each screen.

Aspects

Conjunction (0°) … A relationship in which two celestial bodies are positioned almost exactly together. Their functions blend and are emphasized.

Opposition (180°) … A relationship of bodies positioned directly opposite each other. Represents conflict, tension, or awareness gained through another party.

Trine (120°) … A harmonious, smooth relationship. A favorable aspect representing talent and effortlessly flowing energy.

Square (90°) … An angle representing friction or challenges. A tense aspect that leads to growth when overcome.

Sextile (60°) … An angle representing cooperation and opportunity. A mild, favorable aspect that can be put to use with effort.

Minor Aspects … A general term for supplementary angles such as Semisextile (30°), Semisquare (45°), Sesquiquadrate (135°), and Quincunx (150°).

Orb (Allowed Degree Tolerance) … The allowed range of angular deviation within which an aspect is considered to be in effect. The wider it is, the more aspects will be picked up.

Out-of-Sign … An aspect that is exact by angle, but where the sign combination differs from what would normally be expected. Also called a “dissociate” aspect.

Declination

Declination … The angle representing how far north or south a celestial body is from the celestial equator. This is a “vertical” position distinct from ecliptic longitude.

Parallel (P) … A relationship in which two celestial bodies are on the same side (both north or both south) and have nearly the same declination. Considered to act similarly to a conjunction.

Contra-Parallel (CP) … A relationship in which two celestial bodies have nearly the same declination but are on opposite sides (one north, one south). Considered to act similarly to an opposition.

OOB (Out of Bounds) … A state in which declination exceeds ±23°26′ (the obliquity of the ecliptic). The celestial body is considered to be outside its normal range and to act in an extreme or unconventional way.

House Systems

Whole Sign … The oldest system, in which the entire sign containing the Ascendant becomes the 1st house, with one sign equaling one house. Remains stable even at high latitudes.

Equal … A system that divides the chart into 12 houses of exactly 30° each, starting from the Ascendant’s degree.

Solar Sign … A method in which the sign containing the Sun becomes the 1st house. Used when the birth time is unknown.

Porphyry … A simple division system that trisects the ecliptic arc between the angles (ASC and MC).

Regiomontanus … A medieval system that divides space based on the celestial equator. Commonly used in horary astrology.

Campanus … A system that evenly divides space (the prime vertical) based on the observer’s horizon.

Morinus … A mathematical system that evenly divides the celestial equator and does not use the Ascendant as its starting point.

Placidus … A time-based division system, the most widely used today, based on the time it takes celestial bodies to cross the horizon and meridian. Becomes distorted at high latitudes.

Koch … A time-based division system that emphasizes the birthplace’s latitude. Like Placidus, it becomes difficult to use at high latitudes.

Sensitive Points and Angles

Ascendant (ASC) … The ecliptic degree rising on the eastern horizon at the moment of birth. Marks the beginning of the 1st house and represents the self and first impressions.

MC (Midheaven) … The ecliptic degree on the meridian at the time of birth. Marks the beginning of the 10th house and represents social role and career.

Vertex … The point where the ecliptic and the prime vertical intersect on the western side. Considered a sensitive point for fated encounters and events.

East Point … The ecliptic degree corresponding to the point where the celestial equator meets the eastern horizon. A supplementary sensitive point to the Ascendant.

Part of Fortune (FoP) … A sensitive point calculated from the Sun, Moon, and Ascendant. Indicates a place of good fortune and mind-body harmony. The formula switches depending on day or night birth.

Nodes, Asteroids, and More

Nodes (True / Mean) … The points where the Moon’s orbit intersects the ecliptic. The “True Node” is the actual, fluctuating value, while the “Mean Node” is a smoothed value.

Dragon’s Head / Tail (North / South Node) … The North Node (Head) symbolizes a direction of growth, while the South Node (Tail) symbolizes release or what is already familiar.

Lilith (Black Moon) … The apogee of the Moon’s orbit (the empty focus farthest from Earth). Represents repressed desires and instinctual themes. Comes in Mean, True, and Natural types.

Chiron … A minor body orbiting between Saturn and Uranus. Known as the “Wounded Healer,” representing themes of wounding, healing, and teaching.

The Four Major Asteroids (Ceres, Pallas, Juno, Vesta) … A group of asteroids symbolizing nurturing (Ceres), wisdom and strategy (Pallas), partnership (Juno), and devotion (Vesta).

Techniques

Transit … A technique that examines what angles the actual current (or any specified date’s) celestial bodies form against the natal chart.

Progression (Secondary Progression) … A symbolic technique that advances celestial bodies using “one day after birth equals one year.” Used to view inner growth and the progression of themes.

Solar Arc … A technique that adds the Sun’s post-birth angular progression uniformly to all celestial bodies. Used to identify the timing of major events.

Synastry … A technique that overlays two people’s natal charts and reads the relationship from the aspects formed between their celestial bodies.

Composite … A technique that creates “a single chart of the relationship itself” from the midpoints of two people’s celestial bodies.

Solar Return … The chart for the moment the Sun returns to its natal position. Used to view the trends for that year.

Lunar Return … The chart for the moment the Moon returns to its natal position. Used to view the trends for that approximately one-month period.

Midpoints and Harmonics

Midpoint … The degree exactly halfway between two celestial bodies. When a third body falls there, the forces of the two bodies are said to combine.

Harmonics … A technique that multiplies ecliptic longitude by an integer and “folds” it back, revealing the aspect structure of a specific cycle.

Dodecatemory … A classical technique that further divides one sign (30°) into 12 parts, assigning all 12 signs to each 2.5° segment.

Basic Terms

Ecliptic Longitude … The position of a celestial body (0–360°) measured along the ecliptic, with the vernal equinox point as 0°. The basic coordinate on a chart.

Retrograde … The phenomenon in which a celestial body appears to move temporarily backward as seen from Earth. Indicated with the symbol R.

Ingress … The moment a celestial body moves into the next sign.

Void (Moon’s Void-of-Course Time) … The period during which the Moon will not form any more major aspects before moving into the next sign. Considered a time when matters are hard to settle.

Nutation … A small wobble in the Earth’s rotational axis. This app uses the true value of the obliquity of the ecliptic, including this effect.

UT1 … A time system based on the Earth’s rotation. This app’s Julian Day calculations use UT1 rather than TT.

Rodden Rating … A symbol indicating the reliability of the birth time (AA = most reliable, such as from a birth certificate, through X = unknown). A guide to the certainty of the data.

Appendix: About the App (Calculation Policy)

This app performs astrological calculations without relying on Swiss Ephemeris, instead using the astronomical computation library Skyfield and JPL’s high-precision ephemeris DE440 (the long-span version DE441 for ancient dates). All calculations go through a single unified interface, ensuring consistent results.

Calculation Policy

• The supported range for natal charts is 3000 BCE to 2200 CE, based on DE441. On the data input screen, you can choose the “Era” (CE / BCE) and the “Calendar” (Automatic / Julian / Proleptic Gregorian). BCE dates are internally converted to astronomical year numbering (1 BCE = year 0). Some applied features (such as progressions and asteroids) are only supported from 1600 CE onward.
• For ancient dates (before 1600 CE), Chiron and the four major asteroids are not calculated (because the reliable range of their orbital data is 1600–2100 CE). The 10 planets, Nodes, Lilith, houses, and sensitive points are still calculated.
• For ancient dates (before 1582-10-15), precession is calculated using the Vondrák (2011) long-term precession model (valid for ±200,000 years) to avoid the long-term error of IAU2006. This does not affect calculations for modern dates.
• For ancient dates, because the difference between UT1 and TT (ΔT) is inherently uncertain, the same level of precision as for modern dates is not guaranteed (this limitation is common to every calculation engine).
• The Julian Day uses UT1 (a time system based on the Earth’s rotation). Dates before October 15, 1582 are calculated using the Julian calendar.
• The accuracy target is agreement with Swiss Ephemeris / astro.com to within one minute of arc for modern dates.
• The obliquity of the ecliptic uses the true value, including nutation.
• At high latitudes (60° or above), calculations become unstable, so a warning is shown and Whole Sign is recommended.

The calculation engine supports the 10 planets, True/Mean Nodes, Lilith, Chiron, the four major asteroids, 9 house systems, and various sensitive points (Vertex, East Point, Part of Fortune).