<p>These are known as
<a href="https://en.wikipedia.org/wiki/Two-line_element_set" rel="nofollow">two-line elements</a>
(see also <a href="http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/SSOP_Help/tle_def.html" rel="nofollow">nasa.gov</a>,
<a href="http://www.satobs.org/element.html" rel="nofollow">satobs.org</a>).
On both lines, the first field after the line number is a NORAD ID,
which you can use to query a database such as
<a href="http://www.n2yo.com/satellite/?s=41584" rel="nofollow">N2YO</a>.
The second line gives geocentric
<a href="https://en.wikipedia.org/wiki/Orbital_elements" rel="nofollow">orbital elements</a>
for the epoch given in the first line.
The last line looks like an error estimate by observation analysis software.</p>

<p>The first convenient visualization service I found was
<a href="http://www.orbitalpredictor.com/home/41584/" rel="nofollow">Orbital Predictor</a>,
where I naively pasted the above TLE data with a name less appropriate than "Mentor 7" or "2016-036A."</p>

CC BY-SA 3.0
2016-06-22T23:53:37.837Z
2016-06-23T02:55:44.690Z
2016-06-23T02:55:44.690Z
Mike G
<p>I've been reading about satellite observations (such as <a href="http://sattrackcam.blogspot.co.uk/2016/06/updated-orbit-for-mentor-7-nrol-37.html" rel="nofollow">this one</a>).
The writer uses terms such as these to define the orbit:</p>

<pre><code>1 41584U 16036A   16167.96105997 0.00000000  00000-0  00000+0 0    07 
2 41584   7.5055 353.7008 0046333  41.2140 319.1375  1.00195548    05 

rms 0.004 deg      from 9 obs June 14.70 - June 16.79  (2.09 day arc) 
</code></pre>

<p>What does each variable refer to, and what's the easiest way to view these on a map (either online or in an app of some kind?)</p>

<orbital-elements><satellite><artificial-satellite>
How to understand orbit definitions
tomh
# How to understand orbit definitions

(Asked by: username_0 on 2016-06-22)

I've been reading about satellite observations (such as this one).
The writer uses terms such as these to define the orbit:
1 41584U 16036A   16167.96105997 0.00000000  00000-0  00000+0 0    07 
2 41584   7.5055 353.7008 0046333  41.2140 319.1375  1.00195548    05 

rms 0.004 deg      from 9 obs June 14.70 - June 16.79  (2.09 day arc) 

What does each variable refer to, and what's the easiest way to view these on a map (either online or in an app of some kind?)

**Tags:** orbital-elements, satellite, artificial-satellite


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## 1 answers

### Answer by username_1 on 2016-06-22. Score: 3 | Accepted answer

These are known as
[two-line elements](https://en.wikipedia.org/wiki/Two-line_element_set)
(see also [nasa.gov](http://spaceflight.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/SSOP_Help/tle_def.html),
[satobs.org](http://www.satobs.org/element.html)).
On both lines, the first field after the line number is a NORAD ID,
which you can use to query a database such as
[N2YO](http://www.n2yo.com/satellite/?s=41584).
The second line gives geocentric
[orbital elements](https://en.wikipedia.org/wiki/Orbital_elements)
for the epoch given in the first line.
The last line looks like an error estimate by observation analysis software.

The first convenient visualization service I found was
[Orbital Predictor](http://www.orbitalpredictor.com/home/41584/),
where I naively pasted the above TLE data with a name less appropriate than "Mentor 7" or "2016-036A."


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