Hi all,
With all the recent talk of clocks etc in spacecraft I though you guys
might like this...
http://www.csiro.au/en/Portals/Media/Pulsars-make-a-GPS-for-the-cosmos.aspx
regards
Tim
===
.. and some more information from ESA:
http://www.esa.int/Our_Activ
Le 30 sept. 2013 à 09:19, Hal Murray a écrit :
>
> jim...@earthlink.net said:
>> You also get direction, so for a "navigation" system, you can figure out
>> where you are.
>
> I'm still missing the big picture.
>
> If I'm working off direction, why are pulsars interesting? Why radio vs
> op
jim...@earthlink.net said:
> You also get direction, so for a "navigation" system, you can figure out
> where you are.
I'm still missing the big picture.
If I'm working off direction, why are pulsars interesting? Why radio vs
optical? There are lots of bright stars out there. Why not use th
No I don't have room since I set up my dilution refrigerator for Football
season.
Thomas Knox
> Date: Sun, 29 Sep 2013 14:24:12 -0700
> From: jim...@earthlink.net
> To: time-nuts@febo.com
> Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
>
> On 9/29/13
On 9/29/13 1:52 PM, Tom Knox wrote:
Actually Dr Kent Irwin at NIST has developed very small and extremely sensitive
detectors using SQUIDs.
Not exactly a project that can be duplicated at home though. There are a number
of articles about his work on line.
depends on who's home... Don't you h
m: jim...@earthlink.net
> To: time-nuts@febo.com
> Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
>
> On 9/29/13 3:42 AM, mc235960 wrote:
> >
> > Le 28 sept. 2013 à 14:26, Magnus Danielson a écrit :
> >
> >
> >I think the radio elescope(s) need
There really is no such thing as a 'bright' pulsar. They are something
like 16 Mag at best. This is not exactly naked eye.
-John
===
>
> b...@evoria.net said:
>> Just to satisfy my curiosity: what's easiest to detect galactic pulse
>> emitter (regardless of type), and what's the m
On 09/29/2013 03:11 PM, Jim Lux wrote:
> On 9/29/13 3:42 AM, mc235960 wrote:
>>
>> Le 28 sept. 2013 à 14:26, Magnus Danielson a écrit :
>>
>>
>>I think the radio elescope(s) needed are much smaller. There are
>> apparently 2 pulsar clocks installed here in europe, one in St
>> Catherine's churc
On 9/29/13 3:42 AM, mc235960 wrote:
Le 28 sept. 2013 à 14:26, Magnus Danielson a écrit :
I think the radio elescope(s) needed are much smaller. There are apparently 2 pulsar
clocks installed here in europe, one in St Catherine's church Gdansk and the other in the
European Parliament, Brus
Le 28 sept. 2013 à 14:26, Magnus Danielson a écrit :
> On 09/28/2013 02:15 PM, Jim Lux wrote:
>>
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 satelli
Hi Hal
> The setup is a spinning disk with holes in it.
> Adjust the speed of rotation until it beats with the pulsar.
> I think you need a small telescope for the bright pulsars.
Yes, you are quite right. I recently done this with an 8" amateur telescope
and it is possible to reconstruct the op
b...@evoria.net said:
> Just to satisfy my curiosity: what's easiest to detect galactic pulse
> emitter (regardless of type), and what's the minimum setup to reliably look
> at it, whether it's just during night time, or whatever. Just seeking
> perspective, I haven't just won the lottery.
An o
There's no "yet" to it. I don't play. =)
>
> From: Sanjeev Gupta
>To: Bob Stewart ; Discussion of precise time and frequency
>measurement
>Sent: Saturday, September 28, 2013 10:13 PM
>Subject: Re: [time-n
On Sun, Sep 29, 2013 at 6:55 AM, Bob Stewart wrote:
> I haven't just won the lottery.
Yet. You left out the "yet".
--
Sanjeev Gupta
+65 98551208 http://www.linkedin.com/in/ghane
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To: "Discussion of precise time and frequency measurement"
Sent: Sunday, September 29, 2013 12:13 AM
Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
The sune is hugely bright in the RF.
I've been able to see it at 2.2 GHz with nothing more than a horn
Thanks to all respondents. Perspective is a hard thing to find in this group.
=)
Bob
>
> From: Jim Lux
>To: time-nuts@febo.com
>Sent: Saturday, September 28, 2013 6:33 PM
>Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
>
>
On 9/28/13 3:55 PM, Bob Stewart wrote:
Just to satisfy my curiosity: what's easiest to detect galactic pulse emitter
(regardless of type), and what's the minimum setup to reliably look at it,
whether it's just during night time, or whatever. Just seeking perspective, I
haven't just won the lo
The sune is hugely bright in the RF.
I've been able to see it at 2.2 GHz with nothing more than a horn a foot
or so across and a receiver w/ a NF of maybe 8 dB (cavity preselector &
mixer & IFA... ACL SR-209).
There was a noticable difference between pointing at the sun and in
another direction
>From what I remember, with the 1000' Aricebo dish and pretty good LNA,
there were a literal handful of RF photons per pulse... less than 10
maybe.
-John
===
> Just to satisfy my curiosity: what's easiest to detect galactic pulse
> emitter (regardless of type), and what's the m
Hi
If you are on the surface of the earth, you face the sun from time to time.
That creates some issues that you would not have in a deep space setting. In
deep space you don't have to correct for all sorts of orbital issues as well.
This is one of those - not so easy here - sort of things.
Bo
Just to satisfy my curiosity: what's easiest to detect galactic pulse emitter
(regardless of type), and what's the minimum setup to reliably look at it,
whether it's just during night time, or whatever. Just seeking perspective, I
haven't just won the lottery.
Bob
_
Hi Tom,
On 09/28/2013 07:49 PM, Tom Knox wrote:
> I am just thinking out loud on this, But it seems you could use carrier phase
> from plain star light since the light spectrum from stars have spikes and
> notches which are constant and using the same concept as the Hubble Constant
> a spacecra
Yes, but to use them for interstellar navigation, as suggested, when the
propagation delays are 10,000 years or more complicates things.
What is contemplated is comparing the clocks, as they were thousands of
years ago, where they were thousands of years ago, with largely unknown
motions. You can'
s.
Thomas Knox
> Date: Sat, 28 Sep 2013 09:18:10 -0700
> From: j...@quikus.com
> To: time-nuts@febo.com
> Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
>
> A couple of points:
>
> Pulsars are pretty faint and the only solution to that is antenna
> apertur
> Pulsars are not infrinitely stable. They slowly decay, and, worse,
> randomly undergto 'star quakes' which upset their timing. This was proven
> in the 1960s.
John,
You are correct, but it is a simple opportunity rather than a major problem.
The solution is to monitor multiple pulsar sources.
A couple of points:
Pulsars are pretty faint and the only solution to that is antenna
aperture. We looked at that while doing SETI a ways back. Receivers are
now quite close to the theoretical limit as far as noise temperatuse.
There is very little room for improvement.
Pulsars are not infrinitel
On 9/28/13 7:32 AM, Hal Murray wrote:
jim...@earthlink.net said:
Scrolling down, it looks like they're getting a whopping 0.5 dB SNR on
the Crab Nebula pulsar.
How much of the noise comes from local sources vs thermal or galactic?
These are amateurs, so they're probably not using cryocoole
jim...@earthlink.net said:
> Scrolling down, it looks like they're getting a whopping 0.5 dB SNR on
> the Crab Nebula pulsar.
How much of the noise comes from local sources vs thermal or galactic?
I'm missing the scale factor for the big picture. How big a volume does this
work over before I
On 09/28/2013 02:15 PM, Jim Lux wrote:
>
>>>
>>> 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
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.
Yo
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
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 ma
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
> From: gha...@gmail.com
> Date: Thu, 26 Sep 2013 16:48:14 +0800
> To: time-nuts@febo.com
> Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
>
> On Thu, Sep 26, 2013 at 3:59 PM, REEVES Paul > wrote:
>
> > Some of them might be... you could certainly
On Thu, Sep 26, 2013 at 3:59 PM, REEVES Paul wrote:
> Some of them might be... you could certainly speculate that any
> culture that has attained sufficient technology to make interstellar travel
> possible (and need navigation beacons) would probably have sufficient power
> to 'engineer' th
If there is Alien life on this planet they are most assuredly Time-Nuts.
Thomas Knox
> From: paul.ree...@uk.thalesgroup.com
> To: m...@maxsmusicplace.com; time-nuts@febo.com
> Date: Thu, 26 Sep 2013 08:59:17 +0100
> Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
>
September 2013 08:23
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Pulsars make a GPS for the cosmos
I remember when pulsars were first discovered one speculation was that they
were interstellar navigation beacons established by intelligent life forms.
Rega
, September 25, 2013 7:38 PM
Subject: [time-nuts] Pulsars make a GPS for the cosmos
Hi all,
With all the recent talk of clocks etc in spacecraft I though you guys
might like this...
http://www.csiro.au/en/Portals/Media/Pulsars-make-a-GPS-for-the-cosmos.aspx
regards
Tim
--
VK2XAX :: QF56
Hi all,
With all the recent talk of clocks etc in spacecraft I though you guys
might like this...
http://www.csiro.au/en/Portals/Media/Pulsars-make-a-GPS-for-the-cosmos.aspx
regards
Tim
--
VK2XAX :: QF56if23 :: BMARC :: WIA
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