Registry in RSS

[Frederic V. Hessman]

I agree that there's no obvious immediate reason to worry about  
VOEvent becoming obsolete.  Even if a new and fancy HyperTwitter  
protocol came out and became the world standard for things like being  
informed by your shower controller that someone has changed a filter  
on their telescope half-way around the world, the content of such  
important notices will necessarily be specialized and - on the medium  
term - based on XML.   FITS was designed during a time when the 2880  
blocks were an important constraint on the protocol - now no one  
really cares and is nevertheless happy to continue to use the format.

Rick

On 14 Jan 2010, at 17:03, Dick Shaw wrote:

> Without disagreeing with the fine ideas offered in this thread, I  
> think there may be some value in keeping the conceptual basis and  
> purpose of VOEvent relatively uncluttered. The example notification  
> from IERS is, in its content, really about a non-event (no  
> adjustment to the time reference system is expected to happen at the  
> end of June). A notice about the availability of a new VO resource,  
> while interesting, isn't exactly an event in an astronomical sense.  
> Are these notifications really what VOEvent about? At first blush I  
> would have thought them more appropriate to a news feed.
>
> My $0.02.
>
> -Dick
>
> On Thu, 14 Jan 2010 07:08:38 -0700
> Rob Seaman <seaman at noao.edu> wrote:
>> On Jan 13, 2010, at 12:43 PM, Mike Fitzpatrick wrote:
>>> Not quite what I meant:  I know there are numerous feeds for  
>>> actual "VOEvents", what I was proposing was a feed for "VO Events"  
>>> like the availability of a new resource, overlaying the voevent  
>>> infrastructure, e.g. not that the Catalina Sky Survey found an  
>>> object, but that the CSS is now a broker for "Bob's-really-cool- 
>>> GRB-followup-on-his-GalileoScope" program.
>>> The heretical part is that I see 'events' as a type of message,  
>>> and little difference between a GRB "stream" subscription, a "KBO"  
>>> one, and a "general msg" one.  Is the idea "there is something new  
>>> on the sky" really that much different than "there is something  
>>> new in the Registry"?  Note I'm not quite yet suggesting IVOA  
>>> address these cross-WG issues, neither do I see a need for an  
>>> emerging discussion on a new protocol for Tweet/Rss that shares  
>>> many similarities (at least wrt the 90/10 rule) with existing  
>>> standards.
>> As a timely example of such an astronomical, but not celestial,  
>> event see the appended IERS bulletin published this morning.  This  
>> shares numerous features with the mechanism that Mike is  
>> describing.  It cries out for a semantic representation (rather  
>> than "natural language") - such as an XML standard like VOEvent.   
>> (And an early debate in the WG was whether "event" had a strictly  
>> celestial meaning or also included, for instance, the computer  
>> science definition of events.)
>> Further, it is prospective, rather than retrospective - VOEvent has  
>> to be able to describe events that haven't happened yet, in  
>> addition to reports from the historical record.  A repository of  
>> past bulletins is implicit.  It has an author (Gambis) as well as a  
>> publisher (IERS).  Delivery is transport neutral.  There are  
>> contingent metadata like the publication date and the publisher's  
>> contact information.  The message relies on several widely  
>> promulgated standards, most notably UTC.  Etc.
>> A field of inquiry is layered on many such streams of events,  
>> whether "event" is defined scientifically, technically or simply  
>> logistically.  Does it make sense to invent a new representation  
>> and transport protocol for each stream?  More likely there will  
>> evolve a small number of options that satisfy that 90/10 rule.   
>> Some applications are so idiosyncratic or tightly bound that they  
>> fall into the 10%.  But too often a 90% project chooses a 10%  
>> solution for no good reason - or they choose a too broad solution  
>> (such as the text file below) that is no real solution at all.
>> Is Mike's heresy a high priority for IVOA attention?  I don't know,  
>> but it does seem like a good topic for the TCG workshop whenever  
>> and wherever that may ultimately be held.
>> Rob
>> ---
>> Begin forwarded message:
>>> From: IERS EOP Product Center <services.iers at obspm.fr>
>>> Date: January 14, 2010 5:44:21 AM MST
>>> To: adresc1 at arcas.obspm.fr
>>> Subject: Bulletin C number 39
>>>    INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE  
>>> (IERS) SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES  
>>> SYSTEMES DE REFERENCE
>>> SERVICE DE LA ROTATION TERRESTRE
>>> OBSERVATOIRE DE PARIS                                   61, Av. de  
>>> l'Observatoire 75014 PARIS (France)
>>> Tel.      : 33 (0) 1 40 51 22 29
>>> FAX       : 33 (0) 1 40 51 22 91
>>> Internet  : services.iers at obspm.fr
>>>                                              Paris, 14 January 2010
>>>                                              Bulletin C 39
>>>                                              To authorities  
>>> responsible 
>>>                                                                  
>>> for the measurement  
>>> and                                               distribution of  
>>> time                                     INFORMATION ON UTC - TAI
>>> NO positive leap second will be introduced at the end of June 2010.
>>> The difference between Coordinated Universal Time UTC and the  
>>> International Atomic Time TAI is :		
>>> 		
>>>    from 2009 January 1, 0h UTC, until further notice : UTC-TAI =  
>>> -34 s
>>> Leap seconds can be introduced in UTC at the end of the months of  
>>> December or June,  depending on the evolution of UT1-TAI. Bulletin  
>>> C is mailed every six months, either to announce a time step in  
>>> UTC, or to confirm that there will be no time step at the next  
>>> possible date.
>>>                                          Daniel GAMBIS
>>>                                          Head			
>>>                                          Earth Orientation Center  
>>> of the IERS
>>>                                          Observatoire de Paris,  
>>> France