Hi Lynne
I don’t know how to send a message to you through the Lsstc forum.
Maybe I succeeded now…
I sent you a message on your (what I think is your) email address. However if the email address is not correct then I send it again here
Hello Lynne ! I’m very excited to communicate with you as you seem to be just the very best person to ask ! Someone gave me your name as I posted in theLSSTC forum too. Here down you will see a copy of the message I sent to ask questions on the early LSST strategy before someone answered and gave me your name for further information !
“For the specific question of “will the Pisces/Cetus area be excluded, even partially, at the beginning of the survey?”, perhaps @ljones or other survey strategy experts can provide more details.”
As you will read i am very passionate on dwarf planets, and especially in the sector Pisces/Cetus (don’t ask why ! 
)
(Before anything else you must have comprehension for me as I am not an astronomer ! So it will seem I am kind of ignorant !)
The problem is that this sector is visitable only from July to January (autumn sky). And the survey should start in November …
So to discover a new dwarf planet in this sector that would have these characteristics :
Size : similar to Pluto or Eris (~2000 km diameter)
Semi Major Axis around 75-110 AU (Pluto=40 and Eris=70 AU)
Actual distance : 130-180 AU (more or less near its aphelion)
Albedo : 0.70
Apparent magnitude : 21-22 (if albedo smaller, like 0.15, then 23-24.3… but albédo expected is 0.70 from other dwarf planets of similar size)
What would we need ?
First, to know if there will be at the beginning a reduced area observation (as stated by an unique article [and undated] from Arizona University :
“Already the LSST Year 1 data will cover ~15,000 deg^2 to i-mag 24.3”)
…where Pisces/Cetus could be totally or partially excluded. Knowing that Northern Pisces is not in the Southern sky of the main survey… (but is in the special régions [northern ecliptic] where 10% of the shooting will be done [1 hour per night ] )
Second, that the power of the telescope (or camera) would be sufficient , but it seems that the first 6 months it needs to be calibrated, isn’t it ? In this article they say the magnitude will be 24.3 …well, from my opinion it depends on which filter you use, as we can see here in the red rectangle :
But from this article of LSST website “Criteria to start the legacy survey “: https://rtn-093.lsst.io section 3 “Criteria to begin the LSST” page 5 "
it’s not clear what power (depth) (IQ !) they’re gonna use the 6 first months. I think it will start ONLY if the limit of 0.70” is achieved, but could be BELOW 0.70” if we achieve from the beginning, and from what has been experienced with the ComCam (0.40") there are high probability that it will start already with good IQ Image Quality. (And it will increase with time (the first months) thanks to calibrations) That’s what I understand, but as I said I’m no astronomer and I have a poor English… So if you could help me !
And Please help me to understand what is this Year 1 data 15,000 deg^2 too !
I really wish we would be able to detect this kind of dwarf planet in this sector already before the sector is not visitable anymore (February 2026) and not have to wait until August 2026 (for the question of IQ and the return of this sector in the night sky) or even November 2026 (after Year 1) (for the question of area reduced , if by bad luck part of Pisces/cetus would be excluded)
BTW, maybe even with an IQ of “only” 0.70" or 0.50" this kind of object could be detectable ?!? 
That’s also another thing you could have information about ? And also, knowing it will start already in November, and the sector is visible until February, then the IQ could be only 0.60" in November but already much better 2 months later in January !! And so if we reach 0.40" in January already, then there would be good chances to detect an object like this ! (If Cetus/pisces is not excluded…)
Thank you very much in advance for your informations !!
Best wishes
Raoul
Here is the copy of the message initially sent :
Hello, first of all if you know somebody else that would answer to this question , please give me his name and email address!
I’m very interested in the LSST. And I need to know if the Pisces/Cetus sector will be surveyed at the beginning, which is scheduled for November.
Or if we will have to wait until July-August 2026, when this sector will appear again in the night sky and the Survey will cover the entire planned area, not just a reduced area from which the Pisces/Cetus sector would have been excluded!
Because, I found an article from the University of Arizona undated, so perhaps obsolete, (besides, they are the only ones to talk about that on the entire internet, while the Vera Rubin website only talks about a beginning that will be only limited during the first 6 months by 50% of image quality and speed, but does not mention a reduced area ! : Ref: “Criteria to start the legacy survey”: https://rtn-093.lsst.io ), so I was talking about the article from Arizona University which announces that in the first year (“Year 1 data”) there will only be 15,000 deg^2 covered… …while the complete area is 18,000 deg^2 for the main survey (southern sky) + 4,000 deg^2 (according to my estimate) of specific regions like the northern ecliptic, the galactic plane, the Magellanic Clouds, etc. = total 22,000 deg^2!
7,000 deg^2 are missing!
“Rubin Observatory’s Legacy Survey of Space and Time (LSST) will commence science operations for the main survey in 2024, imaging more than 18,000 square degrees in 6 optical bands to an unprecendented depth over the following 10 years. Already the LSST Year 1 data will cover ~15,000 deg^2 to i-mag 24.3, a fantastic data set for cosmological discoveries.”
Note that they use the future tense to talk about events taking place in 2024! (“LSST willcommence science operations in 2024…”). So this article must be out of date by now… But, who knows?
Because, as I said, on the Vera Rubin Telescope website (and anywhere else), there’s no information about a possible reduction in the observation area in the first year!
So I ask you. Is this correct or not? And if so, in that case will the Pisces/Cetus area be excluded, even partially, at the beginning of the survey?
Cetus and Southern Pisces are in the southern sky, and therefore will be part of the Main Survey (in orange on the sky map), but Northern Pisces is outside it (Northern Hemisphere Sky, northern ecliptic [“special region”] in blue):
The sector Cetus/Pisces is shown as a green square :
It would be great if you had this information, as I have high expectations for this survey in that sector, and I really wish to know if we have to wait 5 months or …14 months !!
With all my gratitude!
PS : and also, I didn’t understand well if the first 6 months it’s absolutely sure that the image quality will be reduced of 50% (0.70" instead of 0.35"), from what I read in "Criteria to start the legacy survey ": https://rtn-093.lsst.io section 3 “Criteria to begin the LSST” page 5 :
“Beginning the scheduled observations no sooner that the system can run at 50% effective speed and with image quality (system contribution) below0.7” is acceptable as long as a clear path to improved performance exists. We assume the path to improvment will arrive at nominal effectiveness (speed 1.0, Image Quality 0.35") within 6 months of the start of survey. Indeed, the ComCam campaign in Q1 FY24 showed the system contribution to image quality is likely as good 0.4" already without full control over the in-dome environment (See On behalf of Rubin Observatory Project, SITCOMTN-149, section 2.2)."
What does it mean ? That they will absolutely respect a protocol where the 6 first months the IQ (Image Quality) is maintained at only 0.70" or is it that 0.70" is only the limit to reach to start the survey (they say : “**below”**0.70" !), but that if it’s possible they will use a better IQ from the beginning ??
That’s also something very important for me as I wish to know what kind of size of possible dwarf planets they could detect in this sector. Typically, some dwarf planets of a similar size than Pluto or Eris (~2000km), but at a farther distance (130-180 AU, instead of 30-70AU for Pluto and 130AU for Eris). An object that would have around 21-22 apparent magnitude, at a distance of around 140-170AU.
So, if it’s not possible to detect with an IQ of 0.70" and that we will have to wait obligatory 6 months for the IQ to increase, then that means that I’ll have, also in that case, to wait until summer 2026… (instead of autumn 2025…)
So any opinion on that too is very welcome !!
Thank you so much to have given me some of your precious time !
Sincerely
Raoul