How to Read an Ephemeris to Track the Planets

An ephemeris looks like a boring grid of numbers. Until you realize it’s a treasure map—showing you exactly where every planet sits, day by day. No software, no login, just raw data that’s been free since NASA started publishing it.

In Short

An ephemeris is a grid of planetary positions. Dates down the left, planets across the top. Each cell shows degree, sign, minute at midnight UT. If the number drops day over day, the planet is retrograde.

1
Get the Data — It's Free
You don't need an app. NASA publishes the raw planetary positions for free (the same stuff astronomers use), but unless you love code, just go to astro.com. Their online ephemeris has a clean grid, no account needed. The paper version, The American Ephemeris, is great if you like to highlight things.
I tried printouts once—waste of ink. Use the digital viewer. It's searchable and you won't lose December's page.
2
Learn the Grid Layout
Look: dates run down the left, planets across the top. Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto. That cell at the intersection? Where that planet is at midnight Universal Time. Got it? Good.
3
Crack the Code: '15 Tau 42'
That string is telling you the planet is at 15 degrees and 42 minutes of Taurus. Think of a degree like an hour—it's split into 60 minutes. Watch the number creep up day by day and you're seeing the planet move.
4
Spot Retrograde Like a Hawk
Retrograde is when the number gets smaller instead of bigger. If Mars goes from 15° to 14° something, it's walking backward. There's usually an 'R' next to it so you can't miss it.
Pro tip: the days leading up to a station, the planet barely budges. If you see degrees barely change for three days straight, something's about to flip—retrograde or direct.
5
Hit Your Own Chart Points
Now superimpose your natal placements. If the ephemeris shows Jupiter at 10° Taurus and your Venus is at 10° Scorpio, that's an opposition transit hitting you right now. You just read your own forecast without a report.
I had a client track her Jupiter return this way. She'd mark the day it matched her natal Jupiter and treat that week like a personal New Year. She said it made her feel less victim to chaos.

Example

I pulled up December 2024: Mars is at '06 Leo 10' on the 6th, '06 Leo 03' on the 7th. The degree dropped, and sure enough, there's an 'R'. It's been retrograde all month. Had a client going through it—every time she snapped at her boss, I'd point to the chart.

Common mistakes

Mixing up minutes and decimals. 42 minutes is 0.7°, not 0.42. That mistake can throw your timing off by days.
Thinking retrograde means the planet reversed course in space. It's an illusion from our speeding Earth perspective—like when a slower car looks like it's going backward as you pass it.
Forgetting that an ephemeris shows midnight UT. If you're in California, yesterday evening's position is still closer to this morning's column than today's midnight.

How Planetary Transits Shape Your HoroscopeThink of transits as today’s sky knocking on the door of your birth chart. The planets never stop moving, and when they hit a sensitive spot in your personal map, that’s what your daily horoscope is reading. It’s why the same day feels completely different for you and your neighbor.What Is a Natal Chart?Think of it as your cosmic fingerprint. It's the exact snapshot of the sky when you were born, using your birth date, time, and place. Unlike a generic horoscope, it’s all about you.