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Re: Date issues
I thank Paul for his kind words about tass and our data.
Careful workers will note that with tass that there is an archive of the
tass list. When uisng the tass data and coming upon a suspect data point
(or for any use for that matter) a careful worker will read the mail list
archive around that time.
There was plenty of discussion about the "17 day error" and about which
data was probably affected. All this information seems to be preserved in
several places now. Whether it will be available in 4005 is another
matter.
Since we are making some effort to preserve the raw and processed data,
perhaps we should preserve the mail list in the same place. It is much
smaller so it would not increase the stored data very much.
If someone knows how to extract the entire mail list by year, and will
send it to me, I will see that it is paired with the tr files.
Tom Droege
> I would like to applaud for Michael results.
>
> 2001 Dec 8 observations are "pre engineering data" , not intended for
> later use.
> Well, in astronomy, any observation is unique. You can direct your
> camera again toward the same field, but all variable objects
> (including asteroids etc.) will not be the same. Even of (very) low
> quality, these early data can be very usefull to check or verify
> periods of variables or to recover asteroids etc. Just, dont ask too
> much from them. Somwtime, just a one bit (yes/no) resolution can be
> useful.
>
> Remember that Kepler got convinced that his theory of planetary orbits
> was correct when he found that an observation of Mars made 2000 years
> before by Aristote matched well his calculations.
>
> I think that a lot of costly observations, not only from TASS, could
> be saved using tricks similar to the one of Michael, for example dead
> bits in a converter or datalink (I recovered once hundreds of tapes
> which had been written with one marginal channel).
>
> Thanks for Tom who did not thraugh out his pre data, and to Michael
> who recovered them.
>
> Best regards, Paul
>
> ****************************************************
> Paul Bartholdi
> 11 chemin de la Barillette
> CH-1260 NYON
> Suisse tel +41 22 361 0222
> ****************************************************
>
>
> On Sun, 27 Feb 2005 16:24:39 -0600 (CST), droege@snapmail.us
> <droege@snapmail.us> wrote:
>> First, thanks to Michael for working on this data.
>>
>> Hmmm! I convert 2452252 to 2001 Dec 8. This is well before I intended
>> any data to be in even the engineering data base. This is back when I
>> was
>> only running TOM1 so this should be TOM1 data.
>>
>> The first data in the tr data base is tr01 and it seems to be from 2002
>> November 26.
>>
>> I don't really object to earlier data being in the data base, but there
>> were a number of things wrong with the early data.
>> This included a period of time when the
>> data
>> was off a big space like 17 days. I had intended to delete this data
>> from
>> the data base.
>>
>> I am delighted that Michael wants to work on this old data to make it
>> good. Just beware.
>>
>> There are some out there in data land that would jump on any error to
>> discredit the whole tass effort. My general policy is to attempt to make
>> full disclosure of everything that might be wrong.
>>
>> This early data is certainly unrelaible. Still, frame to fram variation
>> in a single night's run is probably as good as the current data. It is
>> just a question of where zero is for time and magntude.
>>
>> Tom Droege
>>
>> > Looks like the first try didn't get through. I'll try again without
>> the
>> > images.
>> >
>> > I've put the 6 plots on a page on my website:
>> > http://sallman.tass-survey.org/servlet/markiv/template/Dates.vm
>> >
>> > I will add more plots as I get around to looking at them.
>> >
>> > Mike
>> >
>> > -------- Original Message --------
>> > Subject: Re: Date issues
>> > Date: Sun, 27 Feb 2005 13:58:54 -0600
>> > From: Michael Sallman <msallman@pro-ns.net>
>> > To: Tass <tass@listserv.wwa.com>
>> > References: <421D50D1.8080905@pro-ns.net>
>> >
>> > Well, I've done some more checking, and it looks like the -17 day
>> > adjustment
>> > holds for all 5 days prior to JD 2452252
>> > (2452242,2452243,2452247,2452250,2452251).
>> > I've attached 6 plots, 2 each for DH Peg (it's a RRc with a period of
>> > ~.255d),
>> > DF Hya (EW - period .33d), and the "TASS" star GSC 175-2509
>> > (http://wiki.tass-survey.org/tass/view.do?nodeId=Tass&contentId=TassJ071321.3%2b070414).
>> >
>> >
>> > The first plot is with the dates in the database, the second is with
>> the
>> > dates<2452252 offset -17 days. DH Peg was observed on 2452242, GSC
>> > 175-2509 on
>> > 2452247 and DF Hya on 2452250. In all, I found 7 known short-period
>> > variables,
>> > and 10 "TASS" variables with a significant W-S stat, that were
>> observed on
>> > days
>> > 2542242-2452252.
>> >
>> > On the asteroid front, I found another that was observed in that same
>> date
>> > range, #393 Lampetia on JD 2452251. That one also matches up well when
>> the
>> > -17
>> > day adjustment is applied. Below is a list of the asteroids I've found
>> so
>> > far.
>> > The first 3 listings are the ones that I applied the -17 day
>> adjustment
>> > to. All
>> > the others matched using the dates in the database.
>> >
>> > +---------+-------------------------+---------+--------------+------------+
>> > | jd | asteroid | num_obs | avg(ra) |
>> avg(decl)
>> > |
>> > +---------+-------------------------+---------+--------------+------------+
>> > | 2452243 | Asteroid 23 Thalia | 52 | 36.32468571 |
>> 6.78500000
>> > |
>> > | 2452243 | Asteroid 78 Diana | 9 | 359.25960000 |
>> 9.21990000
>> > |
>> > | 2452251 | Asteroid 393 Lampetia | 8 | 92.81860000 |
>> 7.96990000
>> > |
>> > | 2452252 | Asteroid 23 Thalia | 56 | 31.38493333 |
>> 7.59316667
>> > |
>> > | 2452286 | Asteroid 60 Echo | 17 | 27.61613333 |
>> 8.04036667
>> > |
>> > | 2452301 | Asteroid 712 Boliviana | 9 | 84.43720000 |
>> 7.47030000
>> > |
>> > | 2452310 | Asteroid 556 Phyllis | 11 | 150.90305000 |
>> 5.86080000
>> > |
>> > | 2452311 | Asteroid 654 Zelinda | 45 | 103.96222500 |
>> 7.53675000
>> > |
>> > | 2452312 | Asteroid 654 Zelinda | 51 | 103.82192500 |
>> 7.37295000
>> > |
>> > | 2452313 | Asteroid 654 Zelinda | 29 | 103.69460000 |
>> 7.21493333
>> > |
>> > | 2452319 | Asteroid 374 Burgundia | 8 | 119.08310000 |
>> 7.30030000
>> > |
>> > | 2452322 | Asteroid 125 Liberatrix | 5 | 157.65800000 |
>> 7.33150000
>> > |
>> > | 2452323 | Asteroid 80 Sappho | 9 | 125.34160000 |
>> 5.61910000
>> > |
>> > | 2452413 | Asteroid 31 Euphrosyne | 16 | 185.51395000 |
>> 6.72685000
>> > |
>> > | 2452514 | Asteroid 322 Phaeo | 12 | 341.34807500 |
>> 8.23017500
>> > |
>> > | 2452517 | Asteroid 119 Althaea | 2 | 10.33870000 |
>> 8.71860000
>> > |
>> > | 2452522 | Asteroid 119 Althaea | 5 | 9.79980000 |
>> 8.35910000
>> > |
>> > | 2452522 | Asteroid 2 Pallas | 4 | 308.97750000 |
>> 8.78320000
>> > |
>> > | 2452522 | Asteroid 322 Phaeo | 5 | 339.85570000 |
>> 7.78670000
>> > |
>> > | 2452523 | Asteroid 119 Althaea | 5 | 9.67530000 |
>> 8.27630000
>> > |
>> > | 2452524 | Asteroid 119 Althaea | 4 | 9.54480000 |
>> 8.19120000
>> > |
>> > | 2452524 | Asteroid 2 Pallas | 5 | 308.74120000 |
>> 8.37370000
>> > |
>> > | 2452524 | Asteroid 322 Phaeo | 5 | 339.47910000 |
>> 7.63830000
>> > |
>> > | 2452525 | Asteroid 2 Pallas | 5 | 308.62960000 |
>> 8.16800000
>> > |
>> > | 2452525 | Asteroid 322 Phaeo | 5 | 339.29230000 |
>> 7.55860000
>> > |
>> > | 2452526 | Asteroid 2 Pallas | 5 | 308.52260000 |
>> 7.96190000
>> > |
>> > | 2452526 | Asteroid 322 Phaeo | 5 | 339.10730000 |
>> 7.47620000
>> > |
>> > | 2452527 | Asteroid 2 Pallas | 5 | 308.42040000 |
>> 7.75560000
>> > |
>> > | 2452527 | Asteroid 322 Phaeo | 5 | 338.92450000 |
>> 7.39090000
>> > |
>> > | 2452528 | Asteroid 322 Phaeo | 4 | 338.74340000 |
>> 7.30240000
>> > |
>> > | 2452528 | Asteroid 444 Gyptis | 5 | 12.17960000 |
>> 9.32220000
>> > |
>> > | 2452533 | Asteroid 119 Althaea | 5 | 8.15290000 |
>> 7.28490000
>> > |
>> > | 2452533 | Asteroid 129 Antigone | 4 | 63.39340000 |
>> 6.71460000
>> > |
>> > | 2452533 | Asteroid 2 Pallas | 5 | 307.90750000 |
>> 6.51810000
>> > |
>> > | 2452533 | Asteroid 322 Phaeo | 5 | 337.88480000 |
>> 6.82390000
>> > |
>> > | 2452534 | Asteroid 2 Pallas | 5 | 307.83920000 |
>> 6.31270000
>> > |
>> > | 2452534 | Asteroid 322 Phaeo | 4 | 337.72410000 |
>> 6.72190000
>> > |
>> > | 2452534 | Asteroid 444 Gyptis | 5 | 11.41200000 |
>> 8.47640000
>> > |
>> > | 2452534 | Asteroid 45 Eugenia | 4 | 41.41690000 |
>> 7.91980000
>> > |
>> > | 2452534 | Asteroid 735 Marghanna | 4 | 46.49900000 |
>> 5.79030000
>> > |
>> > | 2452543 | Asteroid 119 Althaea | 5 | 6.28610000 |
>> 6.04900000
>> > |
>> > | 2452543 | Asteroid 137 Meliboea | 4 | 1.40560000 |
>> 8.25990000
>> > |
>> > | 2452543 | Asteroid 322 Phaeo | 5 | 336.50130000 |
>> 5.74620000
>> > |
>> > | 2452543 | Asteroid 444 Gyptis | 5 | 10.01590000 |
>> 7.02640000
>> > |
>> > | 2452547 | Asteroid 137 Meliboea | 4 | 0.75710000 |
>> 7.57710000
>> > |
>> > | 2452548 | Asteroid 444 Gyptis | 4 | 9.16960000 |
>> 6.16000000
>> > |
>> > +---------+-------------------------+---------+--------------+------------+
>> >
>> >
>> > Mike
>> >
>> >
>> >
>> > Michael Sallman wrote:
>> >> I have been doing some more research into the date issue, as I have
>> run
>> >> across
>> >> some known, short-period variables where the TASS data just doesn't
>> >> match up
>> >> with the expected lightcurve(s).
>> >> I have been investigating the very earliest data from 2001-2002
>> (where
>> >> Tom was
>> >> taking 1-2 hour runs of 30-50+ measurements per field), using Michael
>> >> R.'s
>> >> asteroid program to try and pin down the dates.
>> >> It looks like JD 2452243 is off by 17 days (it should be 2452226).
>> All
>> >> the other
>> >> days that I have been able to find asteroids for have matched up
>> >> perfectly.
>> >> There were a few other days before 2452252 that had observations
>> >> (2452242,2452247,2452250,2452251), that I will continue to work on.
>> My
>> >> next step
>> >> (if I can't find any asteroids) is to find other short-period
>> variables
>> >> that
>> >> were observed on these days, and see how their lightcurves match up.
>
>