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To download iObserve from the Mac App Store, you need a Mac with OS X 10.6.6 or later. Learn More.



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Observe the sky like a pro.

iObserve pushes your preparation of astronomical observations to a much higher level. It gathers all the information you need when observing the sky with small and big telescopes, and let you manipulate your nights and targets. It has been built from the ground up by a former ESO support astronomer in Chile.

-- What others have said:

• Best in its class (5 stars) "There is no other app for planing astronomical observations like iObserve. Because of its all-in-one approach, iObserve is also a discovery machine, allowing the user to make connections that were not obvious. And this is perhaps the best thing that can be said about any app. And the author has an amazing roadmap for the app, I can only hope he achieves it. Truly stellar, well done!" (a happy austrian user)

• "Must have for serious astronomers" (5 stars) "Every observer with a mac should have this app, and observers without a mac should buy a mac so they can use this app. It has proven invaluable on multiple observing runs both in the planning phase an while observing." (a happy US user).

• "Efficient observing " (5 stars) "I witnessed the development of this app from its early beta versions and am pleased that it turned out to be much more stable and clean. I use it everytime I go observing at large observatories [...]." (a canadian "Some Dude")

• "iObserve" (5 stars) "The Application works extremely well. I needed support and it was very efficient, i had an answer in a few hours." (some enthusiastic italian 'Mr. Fox')

• "A must have app for all serious astronomers" (5 stars) "This little application has now matured very nicely from its origins a few years ago. (...) It will appeal to serious astrophotographers, deep sky enthusiasts and – of course – professionnal astronomers. Yes, you can find the same information if you scout around the web, but iObserve puts it all in once place, and a lot more besides. I couldn't work without it. And the developer, Cédric, provides outstanding support." (a nice follower from Australia).

iObserve allows you to:

• Easily import any known in SIMBAD or not-yet known object, browse the Exoplanets catalogue or download the latest JPL ephemeris of any known comet and asteroid. All object parameters, properties and references will automatically be kept up-to-date.

• Draw and track multiple colored airmass curves for about 100 builtin observatories on Earth, and get the objects sorted according to the best observing time,

• Draw multiple star tracks with builtin or custom horizon masks, and follow targets across the sky, within customisable night boundaries,

• Find automatically the closest standard stars among 21 000 optical and near-infrared (spectro)photometric or telluric stars stored in 6 different catalogues,

• Download the SDSS, DSS, 2MASS and AAVSO finding charts in multiple photometric bands and with numerous options,

• See the Moon's airmass curve, along with its age, coordinates and illumination fraction, and its minimum separation to any object,

• Easily convert fluxes and magnitudes between different units, et get immediate extrapolations in every bands of the Johnson, Cousins, Strömgren, TYCHO2, SDSS and 2MASS systems,

• Easily convert object coordinates between equatorial, celestal (sidereal) and galactic systems, for any epoch in various units,

• Convert times and dates, and see how the Earth shadow is placed on the world map, relative to your position and that of your observatories,

• Convert small and large distances, and, like all other conversions, save it for future reference.

Moreover, iObserve lets you create new observatories – being a remote location, a professional observatory or simply your backyard. You will then be able to use it like any other builtin observatory.

iObserve also provides its famous times bar with Local Time, UT, Julian Date and the Sidereal Time for all its observatories.

What's New in Version 1.5.1

[UI fixes related to 1.5.0]

For v1.5: Here is finally a big bag of new features and improvements. It's been a year of waiting!

Among the new features:
• A whole new plot view has been added: sky maps! You can now display contours of equatorial, galactic or celestial coordinates in the frame of any of these three same systems. Of course, the local horizon is being shown, as well as horizon masks.
• Exoplanet transits! When available, the transits, with their duration when possible, are displayed in the plots! The list of coming (and past) transits is also provided. Click on one to be transported in the right night setup.
• A whole new Coordinates converter! Instead of loading all objects from DB, a new import feature has been added. It allows you to import lists of coordinates to play with.

Moreover, this version fixes many small bugs in various areas of the app. More precisely:
• The manual import of new objects is being fixed: no need anymore to include yourself the factor 15 in the R.A. field.
• The recognition of multiple objects in the JPL Horizon's output has been improved in the New Small Body sheet.
• The parsing of the observation dates has been improved in the New Small Body sheet.
• A crash occurring in some rare cases when selecting the last entry of the multiple objects table has been fixed, in the New Small Body sheet.
• The import of Horizon Masks has been fixed to work well with the new observatory aliases, in the Startracks.
• A usability issue of the Flux converter has also been fixed. Input wavelength value won't be blocked at '0', thus provoking NaN and infinity numbers when changing the input filter / unit.
• The map view displayed when selecting multiple observatories has also been improved, especially when selecting many observatories with large separations.
• The custom night slider in Star Tracks now display correctly every nights for the whole plot range
• The time zone of the Vienna observatory has been fixed.

Observatories have been added, thanks to active users, for Iran (1), Turkey (2), Tasmania (1), U.S.A (3)., Netherlands (1), and Chile (2).

This app used to cost 30$USD. If you wonder why it is free now, check out, and look for the history of 6 years of development of iObserve!


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View in Mac App Store
  • Free
  • Category: Productivity
  • Updated:
  • Version: 1.5.1
  • Size: 74.3 MB
  • Language: English
  • Seller:

Compatibility: OS X 10.9.0 or later, 64-bit processor

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