# J2000 Epoch coordinate system used in Telescopius: right?
**URL:** https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50
**Category:** General Questions
**Created:** [January 25, 2021, 9:39pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50 "2021-01-25T21:39:00Z")
**Posts on this page:** 13
**Page:** 1
### Author:  [@andrea\_arbizzi](https://forum.telescopius.com/u/andrea_arbizzi)
#### Post date: [January 25, 2021, 9:39pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/1 "2021-01-25T21:39:00Z")
Hi.
I regularly find a difference between telescopius coordinates and those ones used in Asiair - Skysafari .
If i enter telescopius’ coordinates into Asiair or Skysafari, my mount ends somewhere else.
I tried to convert telescopius coordinates here: [Javascript Astronomical Coordinate Converter](http://www.robertmartinayers.org/tools/coordinates.html)
from J2000 into J2021 and everything work. So i deducted that Telescopius uses J2000 epoch.
Am i right? Could you please confirm this?
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### Author:  [@sebagr](https://forum.telescopius.com/u/sebagr)
#### Post date: [January 26, 2021, 12:36am UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/2 "2021-01-26T00:36:13Z")
Yes, Telescopius uses epoch J2000 everywhere, but I’m planning to add a settings pane where you can change the default reported epoch among other things. Hopefully I’ll be able to do it in the coming months.
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### Author:  [@andrea\_arbizzi](https://forum.telescopius.com/u/andrea_arbizzi)
#### Post date: [January 26, 2021, 7:23am UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/3 "2021-01-26T07:23:02Z")
Thanks Sebastian for your quick reply.
And a big thank for your wonderful job at creating but mainly mantaining and optimizing Telescopius…🙂
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### Author:  [@andrea\_arbizzi](https://forum.telescopius.com/u/andrea_arbizzi)
#### Post date: [May 1, 2021, 4:47pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/4 "2021-05-01T16:47:39Z")
Hi Sebastian.
Did you have any chance to add the panel setting where we can change the coordinate system?
Thanks for your effort…
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### Author:  [@sebagr](https://forum.telescopius.com/u/sebagr)
#### Post date: [May 17, 2021, 6:22pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/5 "2021-05-17T18:22:30Z")
Hi Andrea,
I’ve been working on other features, and I’m currently working on making most of the planning sections work offline.
Adding the preferences panel as I had thought will take me some time and that’s why I’m pushing it for later, but I’m thinking I might be able to hack something quickly to show coordinates in JNow when you mouse over them. Do you think that could help in the meantime?
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### Author:  [@andrea\_arbizzi](https://forum.telescopius.com/u/andrea_arbizzi)
#### Post date: [May 18, 2021, 4:12pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/6 "2021-05-18T16:12:02Z")
Hi Seba.
That would be fantastic as well.
You are building the most exciting live deepsky planner platform I’ve ever seen so take your time to put yourself on other most important features, as you told before.
Good luck and many thanks for your efforts to improve and enrich all this huge platform, that is Telescopius…
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### Author:  [@sebagr](https://forum.telescopius.com/u/sebagr)
#### Post date: [June 8, 2021, 9:40pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/7 "2021-06-08T21:40:09Z")
Hi Andrea,
There is new calculator to convert coordinates from J2000 to JNow and vice versa (main menu Toolbox \> Calculators):
This is not exactly the preferences panel I mentioned above (to convert all coordinates in the system automatically according to your settings), but I thought I could make this tool available pretty quickly now.
This update is rolling out later today. I hope this helps until I make the site-wide change to all coordiantes 🙂
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### Author:  [@andrea\_arbizzi](https://forum.telescopius.com/u/andrea_arbizzi)
#### Post date: [June 9, 2021, 5:33am UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/8 "2021-06-09T05:33:25Z")
Hi Sebastian.
Wonderful. Thanks.
I’m looking forward to having this panel in the right place, somewhere in the main page according to my settings, as you mentioned above…
Anyway, thanks a lot for this new tool…
Andrea
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### Author:  [@Celsom](https://forum.telescopius.com/u/Celsom)
#### Post date: [June 27, 2022, 3:44pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/9 "2022-06-27T15:44:35Z")
Hello Sebastian, maybe a year later there is an option to create a mosaic using JNow coordinates. Is it?
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### Author:  [@sebagr](https://forum.telescopius.com/u/sebagr)
#### Post date: [April 28, 2023, 12:48am UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/10 "2023-04-28T00:48:02Z")
Sorry, not yet ☹ Hopefully in the coming months, after a big release with the new targets database and offline capabilities.
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### Author:  [@Christian\_Proulx](https://forum.telescopius.com/u/Christian_Proulx)
#### Post date: [October 14, 2023, 7:32pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/11 "2023-10-14T19:32:34Z")
Sebastian, do we still use the J2000 epoch for Mosaic, cause ASIAIR use JNow?
Any news regarding this topic?
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### Author:  [@sebagr](https://forum.telescopius.com/u/sebagr)
#### Post date: [November 10, 2023, 3:04pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/12 "2023-11-10T15:04:20Z")
Sorry for the late reply. I was very busy finishing the next big upgrade coming Monday, in which I’ll replace the whole DSO database with a much larger and improved version that will even work when we are offline.
Now that this big blocking feature is out of the way, I’ll be prioritizing this issue higher. I’ll let you guys know when it’s done.
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### Author:  [@sebagr](https://forum.telescopius.com/u/sebagr)
#### Post date: [March 1, 2024, 9:04pm UTC](https://forum.telescopius.com/t/j2000-epoch-coordinate-system-used-in-telescopius-right/50/13 "2024-03-01T21:04:52Z")
Starting version 240301.2008, you can now select to see/download the mosaic pane coordinates in J2000 or JNow epochs depending on what you need.
As you switch from J2000 to JNow and back, coordinates and position angles get updated as needed - PA hardly differs, especially far from the celestial poles.
