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Re: TASS Discovers 13 "new" objects, maybe?

Chris and all,

I thought I had answered this publically, but possibly it went only to
Chris.

I think this is just a great result.  Herb does not like the format.  
Well, formats can be fixed when the time comes.  First is the fantastic
achievement to be able to ask the questions that Chris has asked and to
get answers in a reasonable time.  So my hat is off to Chris.  Great
work!  

I don't think this *has* to be a data base where the common man can look
without a little effort.  I think its main use will be a research data 
base.  Is there something at a particular location?  How has it changed 
over time?  What "color" is it?  Give me everything you have where V-I >
n?  This sort of thing.  I think it will be up to the user to a)Learn how
to "talk" to the data base.  b)Translate the returned result into the
desired format.

But we can ask Chris for a human interface.  One suitable for Myself and
others who don't want to get into the details of postgress.  Something 
like what Michael has provided.  But I don't expect to be able to ask 
complicated questions withoug doing some work on learning the language.

Now as to the 13 objects.  My bet is that they are just very red stars.
Ones where V-I > 4-5.  These would not be in the data base since V>16 
(Arne do I have this right?) but might show up in Chris's search because 
he searched R and I.

Tom 



At 04:37 AM 5/20/98 +0000, you wrote:
>I wrote the following in real-time while playing with a newly built
>"test" 
>database.  It contains <1% of the TASS MkIII data.  My intent was just
>to 
>see if the software worked and as a practical test to see if the tools
>would
>support random ad-hoc analysis.  In the process I may have found
>something
>of interest.  I post my notes to show (1) the thing I found and (2) to
>show
>by example what kind of "make it up as you go" analysis can be done. 
>I've
>said it before - you can do this kind of stuff remotely from the comfort
>of 
>your own PC. give it a try.
>
>++++++++++++++++++++++++++++++++
>I have just created my first merged database using a "seeded" catalog.
>I think it works now.  (Stalling for time as the software loads)
>Postgres encourages experimental programming.
>Sometimes a+b is faster to compute than b+a and you can never tell
>which is the best order until you try both.  This weekend, runs were
>taking 10 or 12 hours then crashing.  This morning I was able to merge
>600K observations with a 2.5M entry catalog while getting ready for
>work.
>I am using a P200 with 96 MB RAM and IDE Disks
>
>I made up a feature list for what I call "version 1.0".  This software
>works
>well enough now that I'll post it as version 0.7.  1.0 will contain what 
>I consider a the minimal required feature set for a TASS database  
>The big part missing is photometric calibration (done.  lets look at
>some
>data)
>
>Number of observations  I: 270723  
>                        r: 376031 
>                        v: 0
>                   total : 646754
>                   
>          Catalog entries:2695888
>Entries in "seed" catalog:2522831
>                    Delta: 173057
>                    
>Apparently, of the 646754 observations processed only 173057 were not
>matches
>to Arne's TASSM16 catalog list.  646754 observations is only a drop in
>the
>bucket of available data.  It is only one night's worth.  I picked a
>night
>that was good for Glenn, Nick and Tom. and processed 300+ frames of
>data.
>
>As there are so many non-matches one question to ask is "Are there any
>stars seen multiple times by at least two sites that are _not_ in Arne's
>"complete to mag 16" catalog.
>
>First question to the database:  What is the maximum observation count
>of any star?  Answer "6".  So now we know at least one star was seen by
>six TASS cameras on one night.  Next question: How many where seen six
>times?  Answer "1359".  That's not to many to print.  I'll just browse
>the list of 1359.
>
>The tass catalog now uses a convention when assigning IDs to objects.
>objects from the TASSM16 catalog are given IDs in the range 1 to about
>2,500,000.  Catalog entries added after the seeding process begin with
>10,000,000.  It turns out there are 13 of these entries.
>
>In simple terms.  These are 13 objects in the catalog, each seen by six
>TASS cameras all on the same night and not in Arne's catalog.  Here is
>the
>list:
>
>
>testdb=> select tass_id, ra::float/3600000.0 as ra, 
>                         dec::float/3600000.0 as dec 
>        from tass_cat 
>        where obs_count=6 and tass_id > 10000000;
>        
> tass_id|              ra|               dec
>--------+----------------+------------------
>10003825|2.80183333333333|  1.26503333333333
>10006686|          4.9697|           1.14985
>10006736|5.00426666666667|           0.99155
>10006856|5.09001666666667|  1.20248333333333
>10006898|         5.12235|  1.00616666666667
>10153905|346.615083333333|-0.492915833333333
>10154628|347.089083333333|-0.657548888888889
>10155146|347.446916666667|-0.826282222222222
>10162983|        352.7346|-0.502115833333333
>10171104|358.629316666667|           0.39355
>10171200|358.685933333333|-0.799748888888889
>10171277|       358.72925| 0.998466666666667
>10171878|359.112533333333|-0.587399166666667
>(13 rows)
>
>Now let's look at the raw data for one of these.
>
>testdb=> select * from observ_3i01 where tass_id = 10006686
>testdb-> union
>testdb-> select * from observ_3v01 where tass_id = 10006686 
>testdb-> order by julian_date;
>
> tass_id|sourceid|julian_date|      ra|   
>dec|mag_inst|mag_erro|ccd_no|site_id
>--------+--------+-----------+--------+-------+--------+--------+------+-------
>10006686|     154|  696720180|17887680|4143240|   11032|      54|    
>2|G      
>10006686|     137|  696761119|17889120|4138560|   11740|      64|    
>1|G      
>10006686|     238|  696795010|17890920|4139640|   11297|      33|    
>1|H      
>10006686|     199|  696797350|17892360|4136400|   11667|      49|    
>0|H      
>10006686|     276|  696798680|17893800|4137480|   10930|      35|    
>2|H      
>10006686|     128|  696804620|17891640|4141440|   11125|      85|    
>0|G      
>(6 rows)
>
>
>Interesting, a mag 11 "star".  Wow.  Look at the Ra column.  It goes up
>with JD.  Maybe an Asteroid?  I'll leave further analysis to the experts
>But my guess is that Ra increasing monotonicaly with JD is not caused by
>random chance not with six cameras at two sites.
>
>If anyone wants some data tables let me know what you
>want and I'll e-mail or post the data.  If it turns out we have detected
>13
>"slow mover" asteriods in one night picked at random I am inpressed.
>-- 
>   --Chris Albertson             home: chrisja@jps.net        
>     Redondo Beach, California   work: chris@topdog.logicon.com
>
>