[time-nuts] Pulsars make a GPS for the cosmos

[Magnus Danielson]

On 09/28/2013 01:42 PM, Jim Lux wrote:
> On 9/28/13 4:14 AM, Magnus Danielson wrote:
>> On 09/26/2013 08:25 PM, Tom Knox wrote:
>>> It seems you would need to think of the Pulsar as the clock behind
>>> the GPS sat. You then have an algorithm to add the other need
>>> information at the rec end. To make things easier add to the
>>> constellation one master clock signal with corrections and other
>>> needed info from earth.
>> With enough of them, you can compare their beatings against your local
>> clock and use that to count backwards in order to establish the TAI
>> relationship of your clock in rate and phase, if only reference phase
>> and frequency observations where made and listed. You would not get
>> leap-seconds and UTC, because that needs the earth spin observations,
>> but you can get a fair TAI if you work the numbers.
>>
>
> Don't forget the Doppler and relativistic effects of the earth moving
> around the solar system barycenter.  But that's not much different
> than you do for GPS (e.g. knowing satellite orbits, etc.)
Naturally. You also needs to compensate for their decay-rate as you try
to span longer periods.

You can use them for navigation and time, just like GPS. Even seen a
presentation on that.

Cheers,
Magnus