# Emerald Observatory for iPad

> Comprehensive astronomical data and timekeeping on a single, intuitive display. (iPhone/iPad app by Emerald Sequoia LLC.)

- Source: https://appshunter.io/ios/app/emerald-observatory-for-ipad/id364904759 (this page in markdown: same URL + `.md`)
- Developer: [Emerald Sequoia LLC](https://appshunter.io/developer/284953673)
- Category: Utilities, Education
- Price: Free
- Rating: 4.92/5 from 78 App Store ratings · 54 written reviews indexed
- Age rating: 4+
- Requires: iOS 15.0 · 16 MB
- Languages: Dutch, English, French, German, Italian, Japanese, Chinese, Spanish
- Released: 2010-04-01
- Data updated: 2026-06-10
- Monetization: paid
- User reviews in markdown: https://appshunter.io/ios/app/emerald-observatory-for-ipad/id364904759/reviews.md

## What is Emerald Observatory for iPad?

Emerald Observatory displays a wealth of astronomical information all on one screen, in a unique but understandable format.  Information includes:

- 12- and 24-hour ordinary clock time
- Times of rise and set for the Sun, the Moon, and the 5 classical planets
- Times of the beginning and ending of twilight
- Heliocentric orrery (display of the planets in orbit around the Sun)
- Altitude and azimuth for the same bodies (one body at a time)
- Current phase and apparent orientation and relative size of the moon
- Current regions of day and night on a world map
- The Equation of Time, solar time, UTC time, and sidereal time
- Month, day, year, and leap-year indicator
- Daily alarm (delivered as local notification on iOS 4+ if app is not running)
- Eclipse simulator
- Displayed times are synchronized via NTP to "atomic clock" standard
- Uses iPad location, or the latitude and longitude may be set manually

A setting is available to allow the display to stay on continuously.

Tap on the display to move forward by a month, day, year, hour, or minute.  A detailed manual for the operation of Emerald Observatory can be found at the "Emerald Sequoia LLC Web Site" listed below, at http://emeraldsequoia.com/eo/   

If you are having any trouble with the application whatsoever, please see our FAQ on the support page listed below and then contact us through that page if your problem is not resolved. We take pride in responding promptly to all support email requests but we can't fix it if you don't report it (and we have no way to respond to Customer Reviews on iTunes).

(NTP requires Internet access.  Like all apps Emerald Observatory can not change the device's internal clock.)

## Key features

- Astronomical information display
- Heliocentric orrery
- Rise and set times for Sun, Moon, planets
- Twilight times
- Moon phase and orientation
- World map of day/night regions
- Eclipse simulator

## Recent user reviews (10 of 54)

All indexed reviews: https://appshunter.io/ios/app/emerald-observatory-for-ipad/id364904759/reviews.md

### 5/5 — There is nothing else like it

*2023-10-14*

I’m sad to see Emerald Sequoia go.  Their Observatory is simply nonpareil for clarity.  I use it continually.  There simply is nothing better.  I know.  I’ve looked for something as useful for Linux.

### 5/5 — Time and space are the essence of all.

*2023-09-29*

This was the first and best app that I ever bought.
I aways send a screen picture to friends who need directions for planets.

### 5/5 — My very first app

*2023-09-05*

So sorry to see this go…I found it relaxing

### 5/5 — Essential through out the seasons

*2023-04-03*

Also a longtime user, this app is essential if one wants to know our ‘place’ in the solar system, at any time in the day and in any season. The sun swing from solstice to solstice, the local sunrise and sunset, the variation in the day length over the year, are all tracked precisely in an elegant and beautiful manner. Only one wish- that I had this Emerald Observatory as a large clock on the wall in a place where I could glance at it often!

### 5/5 — Amazing App

*2023-02-04, version 1.5.4*

I’ve had this app since it was introduced many years ago. There is nothing even remotely similar to it, so I consider it unique among the tons of content out there.

As with every app that has been in the market for a long time, I hope the developers continue supporting it. The last update was done a year ago.

### 5/5 — Perfection!

*2022-11-07, version 1.5.4*

From my current Facebook post:
If you have even a casual interest in the night sky and own an iPad, you owe it to yourself to buy the Emerald Observatory app. I’ve been using it for over a decade now and it’s one of the few apps I truly love now just as much as the day I purchased it. The price is probably just a few dollars. As an instructional designer and technologist as well as a software developer, I’m simply in awe of how beautifully and perfectly this app is designed and the amount of information that is clearly displayed on ONE screen. Data visualization geeks and designers, take note! This is how the best of the best do it. Exquisite and elegant in every way.

### 5/5 — The most awesome clock in the store! Think wallpaper! (Wish)

*2022-10-27, version 1.5.4*

I am absolutely mesmerized when I open this app. There is so much there! I would really love it if it could be ported to screen wallpaper.

### 5/5 — Wonderful App

*2022-09-26, version 1.5.4*

I got this app when I get my first iPad, and I love it. It’s so beautiful, and it packs in so much information.

### 5/5 — Awesome

*2022-05-14, version 1.5.4*

The best clock app.

### 5/5 — !

*2021-09-29, version 1.4.6*

I don’t even know what to say, it’s so good.

## Frequently asked questions about Emerald Observatory for iPad

### What does Emerald Observatory do?

Emerald Observatory displays a wide range of astronomical information on a single screen. This includes clock times, rise and set times for celestial bodies, twilight periods, a heliocentric orrery showing planetary orbits, and details about the Moon's phase and appearance. It also shows day and night regions on a world map and simulates eclipses.

### What are the key features of Emerald Observatory?

Key features include a heliocentric orrery, times for the rise and set of the Sun, Moon, and planets, twilight times, current moon phase and orientation, a world map showing day and night, and an eclipse simulator. It also offers various time displays like solar, UTC, and sidereal time, and allows for daily alarms.

### How much does Emerald Observatory cost?

Based on the provided information, Emerald Observatory is a paid application. There are no mentions of in-app purchases or a subscription model, indicating a one-time purchase price.

### What devices is Emerald Observatory compatible with?

The application is specifically designed for the iPad. It utilizes iPad location services or allows manual setting of latitude and longitude. It also requires an internet connection for NTP synchronization.

### How can I navigate through time in the app?

You can navigate through time by tapping on the display. Tapping allows you to move forward by a month, day, hour, or minute. This feature enables users to explore astronomical events and positions at different points in time.

## Version history (last 2 releases)

### 1.5.5 — 2023-09-03

Startup warning about Emerald Sequoia shutdown.

### 1.5.4 — 2021-11-05

Support for iOS 15

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## More apps by Emerald Sequoia LLC

- [Emerald Time](https://appshunter.io/ios/app/emerald-time/id290384375)
- [Emerald Geneva](https://appshunter.io/ios/app/emerald-geneva/id347828665)
- [Emerald Timestamp](https://appshunter.io/ios/app/emerald-timestamp/id371935298)
- [Emerald Chronometer HD](https://appshunter.io/ios/app/emerald-chronometer-hd/id435033000)

All apps by Emerald Sequoia LLC: https://appshunter.io/developer/284953673

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*