Cosmiclogy

Free · No signup · Nothing stored

What was coming up
when you arrived?

Your Sun sign is set by the date. Your Rising sign is set by the minute and the place — the slice of sky that was climbing over the eastern horizon as you took your first breath. It changes every couple of hours, which is why almost nobody knows theirs.

The zodiac band with a rotating horizon A fixed ring of the twelve signs. A line across it marks the observer's horizon. As the Earth turns, the east end of that line sweeps through the ring, and whichever sign sits at the east end is the sign then rising.
Local time — Rising —

A demonstration — not a chart. Enter your birth details below for yours.

01 A momentNot a day — a minute. This is the one thing in your chart that a rounded birth time can genuinely change.
02 A placeTwo people born in the same second, one in Lisbon and one in Lima, do not share a horizon. Yours is where you were.
03 Your eastern horizonThe edge of the sky where things come up. Everything below the line has not risen yet.
04 The sky does not move. You do.The band of twelve signs holds still. The Earth turns once a day underneath it, and carries your horizon around with it.
05 A new sign every two hours or soTwelve signs, one turn, roughly two hours each — though the real figure depends on your latitude, and we will give you yours.
06 Stop the clock at your birthWhichever sign is standing at the east point in that second is your Rising sign. That one. Nothing else about it.
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What it is

The Ascendant: the exact degree of the zodiac that was on the eastern horizon at your birth. It begins your chart, and it describes how you arrive — the first thing a room reads off you, before you have said anything.

How it is worked out

From three numbers: the instant of birth, and the latitude and longitude of the place. Those give the tilt of the sky over that spot, and the horizon cuts the zodiac at one specific degree. There is no interpretation in the arithmetic.

Why the minute matters

The horizon moves about one degree every four minutes. A birth time rounded to the nearest hour can land you in the wrong sign entirely. We will tell you how close to an edge you are rather than let you assume you are safe.

Against Sun and Moon

Sun: where the Sun sat — one sign a month. Moon: where the Moon sat — one sign every two and a half days. Rising: which degree was at the east point — one sign every two hours. Same sky, three different clocks.

Your turn

Three details, and the sky does the rest

All three are needed. A missing birth time is the one gap this calculation cannot work around — it would be a guess wearing a result's clothes.

Local clock time at the place of birth.
Start typing and pick from the list, so the time zone is right.

The twelve Rising signs

One page each: how it reads from outside, what it costs, the planet that runs your chart, and how common it actually is at the latitude you were born.

♈︎Aries Rising♉︎Taurus Rising♊︎Gemini Rising♋︎Cancer Rising♌︎Leo Rising♍︎Virgo Rising♎︎Libra Rising♏︎Scorpio Rising♐︎Sagittarius Rising♑︎Capricorn Rising♒︎Aquarius Rising♓︎Pisces Rising

Questions people ask

These are about the tool. What a Rising sign is, and why two sites disagree, is answered at length in the Almanac.

I don't know my birth time. Can I still use this?
Not for an answer, no — and any calculator that gives you one has quietly picked a time on your behalf, usually noon, which lands on the right sign by luck. What this page does instead is show you every sign that rose at your birthplace that day and the window each one held. If you know roughly when — before breakfast, after dark — that narrows twelve possibilities to two or three, honestly. Your birth certificate or the hospital record settles it for free, and is worth asking for before anything else.
Why do you need my birth place as well as the time?
Because the latitude of the place is inside the calculation. The horizon tilts differently over Oslo than over Nairobi, so the same instant gives a different Rising sign in each. The birth place is not there to look up a time zone — it is one of the three numbers the answer is made of.
Which zodiac does this use?
The sidereal zodiac, measured against the constellations, which is what Cosmiclogy uses in every reading it sells. Most Western sites use the tropical zodiac, measured against the seasons. The two are about twenty-four degrees apart, so they name the same Rising sign for only about one birth in five. Your result tells you what the tropical reading would be, so you can see both rather than wonder which one is broken.
Is this the same as my Lagna?
Yes. Lagna, Ascendant and Rising sign are three names for one thing: the degree of the zodiac on the eastern horizon at your birth. Because this page reads sidereally, the sign it gives you is the one a Vedic chart would call your Lagna.
My birth time is rounded to the nearest hour. Does that break it?
Sometimes, and the page tells you which. The horizon moves about one degree every four minutes, so a rounded time is dangerous only when you are already near the edge of a sign. Your result says how many minutes of birth time sit between you and a different answer — if that number is small, read both signs; if it is over an hour, a rounded time changes nothing.
Do you keep my birth details?
No. No account, no email, nothing written down. The date, time and place are used to work out one answer and are then gone. Nothing on this page needs you to sign up for anything.

Nothing on this page is stored. No account, no email, no row in a database — the details you type are used to work out one answer and then they are gone.

Cosmiclogy reads the Rising sign sidereally, against the constellations. Most Western sites use the tropical zodiac, against the seasons. The two are about twenty-four degrees apart and frequently name different signs for the same birth — why your Rising sign differs between sites.