Plotting an Orbiting Satellite
 

I want to plot a series of X-Y points on a scatter chart
that represent the position of a satellite at a specific
time. X-axis is Right Ascension (RA) and ranges from 0:00:00
to 23:59:59. Y-axis is Declination (Dec) and is -90 to +90.
X crosses Y at 0. I have no problem plotting the points, but
I want to add the local time at which each point occurs as a
secondary X-axis and can't figure out how to do it.

Can anyone help? Thanks.

Mike Hogan

In article ,
says...
I want to plot a series of X-Y points on a scatter chart
that represent the position of a satellite at a specific
time. X-axis is Right Ascension (RA) and ranges from 0:00:00
to 23:59:59. Y-axis is Declination (Dec) and is -90 to +90.
X crosses Y at 0. I have no problem plotting the points, but
I want to add the local time at which each point occurs as a
secondary X-axis and can't figure out how to do it.

Can anyone help? Thanks.

Mike Hogan

Are you sure you want to plot it on the secondary x-axis? You may want
to consider using custom data labels. I assume the local time is in a
column. Use Rob Bovey's XY Chartlabeler (www.appspro.com) or John
Walkenbach's Chart Tools (www.j-walk.com) to add that column as data
labels to the plotted x,y points.

--
Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

There are about 90 points at 10-second intervals for a
15-minute section of an orbit. Labeling each one on
the chart would probably produce something unreadable.
Also, I will be adding a second series with different
X-Y values during the same time period. The ultimate
objective is to show the difference in output of two
different methods of predicting orbital paths. I think
a secondary axis is the way to go, but am open to
suggestions.

Thanks for the input
Mike Hogan


Tushar Mehta wrote:
In article ,
says...

I want to plot a series of X-Y points on a scatter chart
that represent the position of a satellite at a specific
time. X-axis is Right Ascension (RA) and ranges from 0:00:00
to 23:59:59. Y-axis is Declination (Dec) and is -90 to +90.
X crosses Y at 0. I have no problem plotting the points, but
I want to add the local time at which each point occurs as a
secondary X-axis and can't figure out how to do it.

Can anyone help? Thanks.

Mike Hogan


Are you sure you want to plot it on the secondary x-axis? You may want
to consider using custom data labels. I assume the local time is in a
column. Use Rob Bovey's XY Chartlabeler (www.appspro.com) or John
Walkenbach's Chart Tools (www.j-walk.com) to add that column as data
labels to the plotted x,y points.

To plot a secodary x-axis, add a 2nd series (maybe the same series
itself). Then, with the chart selected, select Chart | Chart
Options... | Axes tab.

I still don't think a secondary x-axis makes sense, but it's your
chart... {grin}

--
Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

In article ,
says...
There are about 90 points at 10-second intervals for a
15-minute section of an orbit. Labeling each one on
the chart would probably produce something unreadable.
Also, I will be adding a second series with different
X-Y values during the same time period. The ultimate
objective is to show the difference in output of two
different methods of predicting orbital paths. I think
a secondary axis is the way to go, but am open to
suggestions.

Thanks for the input
Mike Hogan


Tushar Mehta wrote:
In article ,
says...

I want to plot a series of X-Y points on a scatter chart
that represent the position of a satellite at a specific
time. X-axis is Right Ascension (RA) and ranges from 0:00:00
to 23:59:59. Y-axis is Declination (Dec) and is -90 to +90.
X crosses Y at 0. I have no problem plotting the points, but
I want to add the local time at which each point occurs as a
secondary X-axis and can't figure out how to do it.

Can anyone help? Thanks.

Mike Hogan


Are you sure you want to plot it on the secondary x-axis? You may want
to consider using custom data labels. I assume the local time is in a
column. Use Rob Bovey's XY Chartlabeler (www.appspro.com) or John
Walkenbach's Chart Tools (www.j-walk.com) to add that column as data
labels to the plotted x,y points.