Upda es om he LSST Sola
Sys em Science Collabo a ion
James Robinson!
Ins i u e o As onomy!
The Uni e si y o Edinbu gh!
On behal o he SSSC
O e iew
•Wha is he SSSC?!
•Wha ha e we been wo king on - communi y needs?!
•P epa a o y/in-kind So wa e and Ea ly Science wo k
LSST Sola Sys em Science Collabo a ion (SSSC)
Colin O ion Chandle & Meg Schwamb
SSSC Co-Chai s
Ca ie Hol & Ma ia Che nya skaya#
Ea ly Ca ee Rep esen a i es
Aga a Rożek & Gal Sa id#
Publica ion Coo dina o s
Lau a Inno#
C oss Science #
Collabo a ions#
EDI Commi ee Membe
Ac i e Objec s Wo king G oup (Lead: Hen y Hsieh)
Communi y So wa e/In as uc u e De elopmen
Wo king G oup (Lead: Tim Lis e )
Inne Sola Sys em Wo king G oup (Lead: Sieg ied Eggl)
NEOs (Nea Ea h Objec s) and In e s ella Objec s
Wo king G oup (Lead: Sa ah G eens ee )
Ou e Sola Sys em Wo king G oup
(Lead: Ped o Be na dinelli)
Technosigna u es Think Tank (Lead: Jim Da enpo )
Role o he SSSC
1. Ad oca ing o Rubin LSST Sola Sys em
science !
2. O ganising LSST p epa a o y wo k!
3. Facili a ing con e sa ions and connec ing
SSSC membe s be o e da a lows and
a e A " ousing speech", SSSC
Readiness Sp in Ox o d 2024
h ps://lss -sssc.gi hub.io
Cadence Feedback
•We ga e eedback on he SCOC (Su ey Cadence Op imiza ion) 3 d a epo / ecommenda ions#
•We e iewed he inc emen al empla e gene a ion scena ios and impac on he No he n Eclip ic Spu (NES),
Robinson e al 2025#
•We keep eminding abou Sola Sys em “Deep D illing Fields” p oposal using 40 hou s o e he en yea
LSST baseline (see T illing e al. 2018).#
•Small PHA Po en ial Impac o s TOO Recommended by SCOC#
•Co-Chai s ha e asked he commissioning liaison o keep he New Ho izons Ex emely Deep Rubin Su ey
poin ing in mind i a commissioning es could use ha poin ing (see Ka elaa s e al. 2025)
Templa e Gene a ion
•Templa e gene a ion is ele an o any
science case ha equi es eal- ime
ale s in yea 1!
•Templa e gene a ion educes he sky
a ea capable o p oducing ale s - SSO
disco e y & cha ac e isa ion in yea 1
is g ea ly impac ed (up o 50% loss)!
•Gene a ing empla es as soon as
sufficien images a e a ailable
maximises ale p oduc ion!
•Robinson e al. 2025
isi s ha e a empla e co e age 90%; his inc eases o 43.6%
o Δ =3 days. No e ha he small numbe o isi s wi h
co e age >100% a ises due o healpixels ha include only pa
o he isi oo p in ; he oo p in does no align pe ec ly wi h
he healpixel g id, and we may o e es ima e a ea due o
healpixel esolu ion. To jus i y ou selec ion o a 90% empla e
co e age h eshold, we p esen how he dis ibu ion shown in
Figu e 16 changes as a unc ion o ime (Figu e 19). This figu e
shows ha h oughou mos o Yea 1 he e is an app oxima e
bimodal dis ibu ion be ween isi s wi h 0% and 90% empla e
co e age. The e o e, i we we e o educe he 90% h eshold in
ou analysis, we would no include significan ly mo e isi s,
and such low-co e age isi s would be less use ul o a mo ing
objec disco e y (see Sec ion 3.3 o u he discussion).
We also include anima ed figu es showing he cumula i e
sky map isi co e age in Yea 1 o he one_snap_ 4.0
simula ion and he a ious empla e gene a ion simula ions.
Figu es 3and 20 show snapsho s o hese anima ions o he
fil e , whe e he empla e simula ion is Δ =7 days. These
anima ions highligh he ime lag when empla e gene a ion
mus be conside ed, and he pa chie co e age when isi s
wi hou empla es a e ejec ed.
3.3. Sola Sys em Disco e y Me ics
Fo hose obse a ions ha ha e su ficien empla e co e age
a he ime o he exposu e, we can analyze he Yea 1 SSO
me ics, conside ing only isi s ha had a ac ional empla e
co e age o 90%, as discussed in Sec ion 3.2 abo e. We no e
ha up o his poin ou analysis has ocused on healpixels wi h
a size compa able o LSST pa ches (¢
13. 7), and now, we a e
conside ing isi s o he size 3
.5. We ha e made he
conse a i e assump ion ha he SSP pipeline will only be
e ec i e o isi s wi h a su ficien le el o empla e co e age.
Cu ing isi s wi h <90% empla e co e age will na u ally
emo e many healpixels ha did ha e empla es; he sky maps
shown p e iously (e.g., Figu e 6, e c.)would be significan ly
spa se i eplo ed o only isi s wi h 90% empla e
co e age a he han indi idual healpixels wi h empla es.
Figu e 21 shows he esul s o he disco e y me ic o
objec s wi h h ee pai s o de ec ions o e a 15 nigh pe iod. As
desc ibed in Sec ion 2.7, we ha e conside ed a ange o
dynamical popula ions: MBAs, NEOs, PHAs, TNOs, and
OCCs, wi h a maximum pe ihelion dis ance o 5 au (OCC_ 5)
and 20 au (OCC_ 20). The di e en o bi s and physical
p ope ies o hese dis inc popula ions ha e a s ong influence
on hei disco e y. The me ics a e di ided in o wo
componen s looking a he absolu e magni ude bins ha
ep esen he “b igh ”and “ ain ”objec s o each dynamical
popula ion (see Table 3)in o de o assess he e ec s o la ge
and small SSOs sepa a ely.
We p esen he me ic esul s o each empla e gene a ion
imescale ela i e o he de aul one_snap_ 4.0 cadence
simula ion whe e he p esence o empla es is implici ly
assumed (i.e., all isi s a e capable o making SSO de ec ions
and ale s). Figu e 21 shows ha he equi emen s o empla e
gene a ion (ac oss all imescales es ed he e)will s ongly
impac disco e y in Yea 1, wi h dec eases o ens o pe cen in
he MAF disco e y me ic. The disco e y o ain objec s is
mo e s ongly a ec ed; ain e objec s a e obse ed wi h lowe
signal- o-noise a io (SNR), so he e a e ewe possible
de ec ions in he baseline. The e is a la ge ac ional loss o
de ec ions due o a lack o empla es compa ed o he b igh
popula ion. Fu he mo e, he e a e la ge di e ences in
disco e y be ween di e en SSO popula ions such as he
OCCs and MBAs; his is p ima ily due o how hese objec s
mo e ac oss he sky. The inne sola sys em popula ions
gene ally mo e as e ; he e o e, an MBA is mo e likely o pass
h ough sec ions o he sky wi hou empla es and no ge
enough de ec ions o be disco e ed. In compa ison, a slowe
mo ing TNO in he ou e sola sys em co e s less sky du ing
disco e y; i s de ec ion equi es a smalle a ea o he sky
ha ing empla es and is he e o e mo e likely. Fo each
popula ion, as Δ inc eases, he e a e only modes dec eases
o a ew pe cen in disco e y, which is small compa ed o he
o e all e ec o empla e gene a ion.
We pe o med an addi ional analysis assessing how
di e ences in he su ey cadence co e ing he eclip ic plane,
whe e mos SSOs a e loca ed, a ec disco e y. We spli he
one_snap_ 4.0 su ey in o isi s wi h decl. 0
o
, whe e he
NES is loca ed, and decl. <0
o
, whe e he sou he n pa o he
eclip ic is p ima ily sampled by he WFD cadence. Following
he p e ious me hodology, hese se s o isi s we e analyzed
sepa a ely by he MAF SSO disco e y me ics, he esul s o
which a e shown in Figu e 22. Fo isi s wi h decl. <0
o
, he e
is an inc ease in he ac ion o SSOs disco e ed du ing
empla e gene a ion compa ed o he p e ious analysis o he
whole sky. Acco dingly, he d op in disco e ies is a g ea e
o he decl. 0
o
isi s. This demons a es ha losses in he
NES egion a e domina ing he o e all educ ion in SSO
disco e ies du ing Yea 1, whe eas he a eas o he eclip ic
sampled by he WFD a e no as se e ely impac ed. In Yea 1,
he NES ecei es ∼75% ewe isi s han he WFD; his means
ha losing 4 isi s o empla es is a g ea e p opo ional loss,
which esul s in a la ge ac ion o missed SSO de ec ions.
Fu he mo e, we ha e only conside ed SSO disco e y o isi s
wi h 90% empla e co e age a he han o all healpixels
wi h empla es. This means ha he le el o he co e age in he
NES shown in Figu es 6, e c. is ac ually much lowe when only
isi s wi h 90% empla e co e age a e conside ed. Only a
small numbe o isi s in he NES mee he empla e
equi emen s, which explains he s ong dec ease in he
disco e y me ic o his egion.
Figu e 16. His og am o he ac ional empla e co e age o all Yea 1 isi s,
which is de e mined om he numbe o healpixels wi hin he isi oo p in
wi h empla es. Resul s a e shown o he one_snap_ 4.0 cadence
simula ion, assuming a ange o empla e gene a ion imescales. The peak a
ze o consis s mainly o he images used o make he empla es (see Table 5).
17
The As ophysical Jou nal Supplemen Se ies, 279:9 (25pp), 2025 July Robinson e al.
field (P. Yoachim 2024). These spa ial and o a ional di he s
will lead o nonuni o m co e age a subde ec o leng h scales;
he e o e, he c ea ion o a empla e image will no be as simple
as selec ing a numbe o images in a gi en fil e a he same
field poin ing. Due o he shape o he LSSTCam oo p in , he
gaps be ween CCD de ec o s, and gaps be ween a s (g oup-
ings o CCDs wi hin LSSTCam), he di he ing be ween
obse a ions equi es ha he LSST da a managemen and
educ ion pipelines educe noncoadded obse a ions a he
indi idual CCD le el. Thus, he c ea ion o image sub ac ion
empla es will also be pe o med on a size scale simila o
LSSTCam CCDs. A simila s a egy has been success ully
employed in he Suba u Telescope’s Hype Sup ime-Cam
Su ey da a educ ion pipelines (J. Bosch e al. 2018).
The LSST da a managemen pipelines di ide he sky in o a
common pixel g id o o e lapping squa e 1
.6×1
.6 iles, dubbed
“ ac s,”which a e hemsel es subdi ided in o 7 ×7“pa ches”
(see Figu e 4; and J. Bosch e al. 2018; J. Swinbank e al. 2020).
I akes nine ac s o ully co e a single LSSTCam poin ing,
which spans 3.5 deg
2
. A single pa ch is he app oxima e size o
an LSSTCam CCD de ec o wi h dimensions o 13¢
.7×13¢
.7.A
pa ch is comp ised o 4100 ×4100 pixels wi h a pixel scale o
0
.
2 pe pixel, ma ching ha o LSSTCam (Ž. I eziće al. 2019;
J. Swinbank e al. 2020), and each pa ch o e laps by 100 pixels
on a side wi h hei neighbo ing pa ches. Fo a de ailed o e iew
o ac s and pa ches, we e e he eade o he summa y
pape o he Rubin Obse a o y’s Da a P e iew 0.2/Da k
Ene gy Science Collabo a ion (DESC)Da a Challenge 2 (DC2;
LSST Da k Ene gy Science Collabo a ion 2021, he ea e
LSST DESC).
A pa ch is he smalles uni ha will be handled by Rubin
da a-p ocessing pipeline. Templa e gene a ion and, subse-
quen ly, image sub ac ion will be pe o med a he pa ch le el.
Figu e 5shows an example o he co e age in a single fil e o
a andomly selec ed pa ch chosen om he simula ed Da a
P e iew 0.2/DC2 (LSST DESC)Yea 1 Da a Release image
empla es. The impac om o a ional di he s, spa ial di he s,
chip gaps, a gaps, masked pixels a de ec o edges, and
sa u a ed sou ces can be seen. An LSST pa ch will he e o e
no ha e uni o m co e age ac oss all o i s pixels. This mus be
accoun ed o when es ima ing he Yea 1 inc emen al empla e
p oduc ion a es.
2.3. HEALPix Sky Maps
To (1) ack he Yea 1 isi s in a gi en a ea o he sky
sui able o making an inc emen al empla e and (2) o iden i y
which obse a ions ha e su ficien empla e co e age o p oduce
ale s and sola sys em de ec ions in Yea 1, we pa i ion he sky
using a HEALPix map (Hie a chical Equal A ea isoLa i ude
Pixeliza ion
18
; K. M. Gó ski e al. 2005)as shown in Figu es 1
and 2. This pixeliza ion p oduces subdi isions o a sphe ical
su ace in which each healpixel has equal su ace a ea and a
esolu ion de e mined by nside, such ha he whole sky is
di ided in o 12 ×nside
2
healpixels. I is oo compu a ionally
expensi e o conside inc emen al empla e gene a ion a he
indi idual pa ch pixel le el as each pa ch has 16,810,000
pixels. Ou bes comp omise is o ins ead ocus on he pa ch as
ou smalles size elemen and use nside =256. This esul s in
healpixels wi h a esolu ion o app oxima ely 13¢
.7, which is
compa able in angula size o a pa ch. We no e ha his esul s
in a HEALPix sky map g id ha is simila o, bu no exac ly
aligned wi h, he pa ch/ ac essella ion ha he Rubin
Obse a o y Da a Managemen pipelines a e using. By using
a healpixel esolu ion compa able o he pa ch size, we on
a e age balance he p oblems o o e sampling (la ge nside,
high esolu ion healpixels)and unde sampling (small nside,
low esolu ion healpixels)when making ou HEALPix
inc emen al empla e co e age sky maps.
2.4. Yea 1 Templa e Gene a ion Timescales
As Yea 1 o he su ey p og esses and images a e aken
acco ding o he p edefined su ey s a egy, he sky co e age
inc eases nigh ly. Howe e , o ope a ional easons (such as
cons ain s on s a fing and compu a ional esou ces), empla e
p oduc ion is unlikely o occu nigh ly, bu ins ead only on
ce ain nigh s wi h some imescale (e.g., days o weeks).
Templa e gene a ion imescales ha e no ye been finalized by
he Rubin Obse a o y Ope a ions and Da a Managemen
Teams, bu hey a e planning o a egula schedule (e.g.,
app oxima ely mon hly; M. L. G aham e al. 2020; L. P. Guy
e al. 2023). We he e o e explo e a ange o empla e
gene a ion imescales, Δ =3, 7, 14, and 28 day in e als
om he s a o he one_snap_ 4.0 simula ion.
Figu e 1. Le : A sky map showing he o al numbe o isi s, in all fil e s, a he end o Yea 1 o he one_snap_ 4.0_10y s obse ing s a egy (Mollweide
p ojec ion). This sky map was gene a ed using a HEALPix (Hie a chical Equal A ea isoLa i ude Pixeliza ion; K. M. Gó ski e al. 2005) esolu ion o nside =256.
The plo s a e cen e ed on R.A. α=0°and decl. δ=0
o
, wi h R.A. inc easing o he le . R.A. and decl. lines a e ma ked e e y 30
o
. The main sky egions o he su ey
a e labeled as ollows: Low-dus Wide–Fas –Deep (WFD), No h Eclip ic Spu (NES), Galac ic plane (GP)WFD, dus y (Galac ic)plane, sou h celes ial pole (SCP),
Deep D illing Fields (DDFs), and he Vi go clus e . Righ : he colo map deno es he on-sky ex en o he di e en su ey egions.
18
h p://healpix.sou ce o ge.ne
4
The As ophysical Jou nal Supplemen Se ies, 279:9 (25pp), 2025 July Robinson e al.
Da a Release Schedule
•Recommenda ions o he Ve a C. Rubin
Obse a o y Ea ly Science Schedule
(Schwamb e al. 2025)!
•Eclip ic co e age in he Science Valida ion
su ey is g ea o us!!
•The SSSC ecommends eleasing DP2
wi h SV only and s a ing he main su ey
asap.
SSSC In-Kind Con ibu ions
43 eams ou side he US and Chile a e making in-kind con ibu ions o Rubin Obse a o y and LSST Science in e u n
o LSST da a igh s.!
Th ee selec ed In-kind Con ibu ion p og ams o SSSC:!
•CAN-CAN-S7 (PI: Wes F ase ): Pipeline de elopmen /RAFTs!
•HUN-KON-S1 (PI: Gyula Szabó): Fo ced pho ome y!
•ITA-INA-S11 (PI: Lau a Inno): Ad anced ac i e objec s’ de ec ion & cha ac e iza ion!
One In-Kind con ibu ion suppo ing mul iple SC’s:!
•UKD-UKD-S16 (PI: Meg Schwamb & Colin Snodg ass): Adle b oke !
Also an in-kind ollow-up p og am:!
•NZL-AUK-S1 (PI: Michele Bannis e ): Agile op ical ollow-up o ansien s and Sola Sys em objec s disco e ed by
he LSST a M John Ō ehiwai Obse a o y
Resea ch Announcemen s Fo The Sola Sys em (RAFTs)
(Lau a Buchanan, Wes F ase )
•Publica ion sys em designed o quickly
issue sho , ci able announcemen s
ele an o Sola Sys em esea ch.!
•Pe manen DOIs assigned o each.!
•In eg a ed wi h he LSST communi y
o um o encou age u he
collabo a ions and engagemen .!
•Mode a ion p ocess o ensu e high-
quali y and ele an publica ions.
S a us o he SSSC So wa e Roadmap
Schwamb e al. 2019
Mos o he u gen so wa e needs ha e someone
wo king on de eloping communi y ools
LSDB no ebook de eloped a he July 2025 LINCC F amewo ks Wo kshop and Hacka hon!
& sbpy!
Much o ou high p io i y pos Yea 1 i ems a e being ackled
•P edic ed disco e ies, DP0.3 and now
So cha: Mu agh e al. 2025, Ku lande
e al. 2025!
•Mos objec s disco e ed in i s 2 yea s!
•>5 million new objec s o be disco e ed,
ypically wi h 100s o obse a ions
SSOs in LSST
million p esen ly known objec s ( e ie ed 2025 Janua y 31
om he SBDB; J. D. Gio gini e al. 1996)a e among hese,
he LSST will measu e p ope ies o some 3.9 million new
small bodies, a 3.6×inc ease o e he cu en numbe .
The disco e y a e as a unc ion o su ey ime is no
cons an . The op panel in Figu e 3shows he on-sky
dis ibu ion o disco e ies o he ull 10 y du a ion su ey.
The middle and bo om panels show he disco e ies made in
he i s 2 y and he las 2 y , espec i ely. A ew de ails s and
ou . As expec ed, mos objec s a e disco e ed wi hin 10°o he
eclip ic, domina ed he MBAs ha cong ega e he e. Nex , he
sou he n po ion o he eclip ic is mode a ely dense wi h
disco e ies han he NES a ea, e lec ing he ewe obse a-
ions Rubin will make in he NES egion. S ill, obse ing he
NES is ex emely impo an , as 17% o Rubin disco e ies a e
made in ha egion, including 11% o TNOs. We also spo
some b igh ci cles, mos no ably he one a ound
(α,δ)∼(150
�
, 2
�
). This is a deep d illing ield, obse ed
ea ly in he su ey and he e o e a sou ce o a la ge numbe o
ea ly disco e ies. The e a e six DDFs sp ead ac oss he sky;
he o he s a e less p ominen in his igu e because hey lie a
high eclip ic la i udes. The WFD-NES bounda y on he eclip ic
is highligh ed by an o e densi y o inne sola sys em objec
disco e ies. Second, he e a e some “ e ical” whispy pa e ns
in he disco e ies, esembling wa es oughly pe pendicula o
he line o he eclip ic. These a e due o a combina ion o
wea he and nigh ly obse ing pa e ns ea ly in he su ey, and
a e no especially meaning ul.
We ind ha mos objec s a e disco e ed qui e ea ly in he
10 y su ey, wi h dis an popula ions quickly eaching high
comple eness (see Figu e 6). As o DR3, LSST is expec ed o
disco e 72% o TNOs, 68% o Jupi e T ojans, 69% o
MBAs, and 53% o d>140 m NEOs. Wi h he disco e y o a
la ge ac ion o objec s, accu a e popula ion es ima es will be
possible quickly, con ingen only on su ey cha ac e iza ion
o debiasing. While we do no model Sednoids, Plane 9, o
o he ex eme TNO (a>250 au, q>37 au)popula ions he e,
hey will be disco e ed ea ly wi h he o he TNOs, allowing
o an ea ly e-e alua ion o he e idence o he Plane 9
hypo hesis (C. Shankman e al. 2017; P. H. Be na dinelli e al.
2020; M. E. B own & K. Ba ygin 2021; K. J. Napie e al.
2021; A. Si aj e al. 2025).
Mo e e ealing is wha compa ing he h ee panels ells us:
ha mos disco e ies occu ai ly ea ly in he su ey, wi h e y
ew new objec s being disco e ed by yea s 9 and 10.
Quan i a i ely, 70% o objec s a e ound wi hin he i s 2
y , wi h he ac ion being la ge he mo e dis an he
popula ion is (i.e., 72% o TNOs, 73% o Jupi e T ojans,
69% o MBAs, and 53% o d>140 m NEOs), b inging
oppo uni ies o ea ly science (see Sec ion 4). This is caused
by he dep h and each o Rubin: as i sweeps h ough he sola
sys em, wi hin one synodic pe iod, i disco e s mos objec s
ha a e b igh e han i s limi ing magni ude o e a ∼15 day
linking window. The subsequen yea s hen ill he gaps caused
by wea he and pick up addi ional objec s ha ha e mo ed
owa d pe ihelion and/o a e a he limi o de ec abili y. In
con as , popula ions wi h a ela i ely cons an lux o new
objec s include he small NEOs (see Sec ion 3.2)and
in e s ella objec s (no discussed he e).
As we ha e no ed, ou simula ed ca alog comp ises 1.145
billion single-epoch de ec ions ha enable a o al o 5,356,423
objec s o be disco e ed. O he 1.145 billion, some 43 million
(∼4%)belong o objec s ha a e no obse ed in a pa e n
sui able o success ul linking. Fo example, an objec wi h a
o al o jus i e obse a ions would no be linkable. An objec
wi h 50 obse a ions sp ead e enly ac oss he 10 y would also
escape de ec ion. Such obse a ions will be in he LSST sou ce
ca alog, bu won’ be ecognized as belonging o mo ing
objec s. They may be linked ou side o egula LSST
p ocessing by ano he algo i hm o p eco e ed when objec s
a e disco e ed la e by o he su eys. S ill, he in e se is
possibly mo e imp essi e— hese esul s imply ha some 96%
o all mino plane obse a ions in he LSST will be linked,
Table 5
Summa y o LSST Sola Sys em Ca alog P ope ies
Componen
Cu en ly
Known Objec s Obse ed Median A c
Median Numbe o
De ec ions High-quali y Colo s
High-quali y Ligh
Cu es
NEOs 37,932 127,040 ±557 96 day 23 4418 ±66 (3.5%)471 ±22 (0.3%)
MBAs 1,380,217 5,087,541 ±1661 9.0 y 160 1,666,184 ±1291 (32.8%)421,365 ±649 (8.3%)
Jupi e T ojans 15,134 109,367 ±331 9.0 y 193 45,221 ±213 (41.3%)5846 ±76 (5.3%)
TNOs 5,246 37,002 ±192 9.5 y 234 16,651 ±129 (45.0%)1057 ±213 (2.9%)
No e. Cu en ly known quan i ies e ie ed om 2025 Feb ua y 24 om he SBDB (J. D. Gio gini e al. 1996). P o ided 1σsample unce ain ies a e he squa e oo
o he popula ion size, since ou popula ions a e made o objec s d awn independen ly and iden ically. Sample unce ain y con ibu ed by he upscaled small NEO
popula ion is upscaled by he same ac o .
Figu e 4. F ac ion o simula ed objec s disco e ed (“disco e y comple e-
ness”) o NEOs, MBAs, and Jupi e T ojans. The NEO popula ion is
measu ed in diame e while he MBAs and T ojans a e measu ed in H
.
B igh -end loss o comple eness is due o b igh sou ce sa u a ion. The H
and
diame e axes a e aligned assuming a e e ence albedo o 0.25. The Jupi e
T ojans, being ela i ely spa ially con ined, d op sha ply om e y high o
e y low comple eness o e a small ange o absolu e magni udes. NEO
comple eness sh inks, bu does no each ze o e en a diame e s o 1 m.
9
The As onomical Jou nal, 170:99 (19pp), 2025 Augus Ku lande e al.
Figu e 3. Hea map o he (equa o ial)on-sky posi ions o disco e ed objec s o e he ull su ey ( op panel), i s 2 y (second panel), and inal 2 y (bo om panel).
Disco e ies a e concen a ed on he eclip ic plane. The disco e ies in he i s 2 y comp ise a la ge ac ion o he ull su ey’s disco e ies, hough la e-su ey
disco e ies a e s ill subs an ial. B igh objec s in he NES ha happen o no be disco e ed ea ly in he su ey a e o en disco e ed as hey en e he WFD su ey
a ea, leading o an o e densi y o objec s a he wes e n NES-WFD bounda y and an unde densi y a he eas e n bounda y.
8
The As onomical Jou nal, 170:99 (19pp), 2025 Augus Ku lande e al.
Figu e 3. Hea map o he (equa o ial)on-sky posi ions o disco e ed objec s o e he ull su ey ( op panel), i s 2 y (second panel), and inal 2 y (bo om panel).
Disco e ies a e concen a ed on he eclip ic plane. The disco e ies in he i s 2 y comp ise a la ge ac ion o he ull su ey’s disco e ies, hough la e-su ey
disco e ies a e s ill subs an ial. B igh objec s in he NES ha happen o no be disco e ed ea ly in he su ey a e o en disco e ed as hey en e he WFD su ey
a ea, leading o an o e densi y o objec s a he wes e n NES-WFD bounda y and an unde densi y a he eas e n bounda y.
8
The As onomical Jou nal, 170:99 (19pp), 2025 Augus Ku lande e al.
Rubin Fi s Look
•Fi s da a om LSSTCam (June 2025), 1185
obse a ions (ug i) spanning 13 days!
•~340,000 de ec ions o ~2100 new as e oids
(high cadence)!
•Pho ome y a ailable on MPC (also compiled
by h ps://b612.ai/ ubin-mpc-downloads/)
NSF–DOE Ve a C. Rubin Obse a o y
An excellen esou ce o
as e oid ligh cu es and colou s
(G eens ee e al. coming soon)
10
3.3. Addi ional alida ion540
While he wo me hods desc ibed abo e a e simila in541
many ways, he e a e a ew key di↵e ences ha can lead542
o a sligh di e gence in he esul ing o a ion pe iod543
de e mina ions and ligh cu e ampli udes (which a e544
used o colo de e mina ions) be ween he wo me h-545
ods. Fi s is he p e-p ocessing o he da a. In he546
LSM me hod, we used he MPC’s p edic ed V magni-547
ude o co ec o dis ance and phase angle a ia ion.548
In he Fou ie me hod, he obse ed magni udes used549
dis ances and phase angles om JPL Ho izons and man-550
ually i he phase unc ion. Nex , bo h me hods u ilized551
a weigh ed leas -squa es me hod o i he Fou ie se ies552
o he da a. Howe e , in he LSM me hod, we excluded553
obse a ions ha a e 3away om he mean magni ude554
be o e he i was made, while o he Fou ie analysis,555
obse a ion exclusions we e made du ing he i i e a-556
ions, po en ially leading o di↵e ences in he obse a-557
ions excluded om he ligh cu e i . The wo me hods558
also used di↵e en o de s in he Fou ie se ies: LSM con-559
side ed only 2nd o de Fou ie se ies, while he Fou ie 560
analysis conside ed o de s k=2 ok= 6, choosing he561
bes op ion ou o he possible i s. The powe o he562
i ed solu ions we e also calcula ed di↵e en ly (LSM:563
Equa ion 4; Fou ie : Equa ion 5). The LSM me hod564
addi ionally excluded solu ions wi h only a single peak,565
choosing he peak wi h highes powe and wo maxima566
wi hin one phase. In he Fou ie analysis, we did no ex-567
clude possible pe iod solu ions wi h a single peak, how-568
e e , i a single-peaked solu ion was ound o be he569
bes i , he pe iod co esponding o ha single-peaked570
solu ion was doubled and chosen as he bes - i solu ion.571
These di↵e ences in he wo me hods could po en ially572
lead o di↵e en bes - i o a ion pe iods and de i ed573
ampli udes and colo s esul ing om he wo algo i hms.574
These po en ial di↵e ences a e discussed in g ea e de-575
ail in Sec ion 4below as pa o he p esen a ion o ou 576
esul s. As discussed, ou esul s ag ee o he majo i y577
o he objec s in ou inal sample o wi hin 10%, wi h578
he di↵e ences in he bes - i o a ion pe iods and co -579
esponding ampli udes and colo s ag eeing o wi hin a580
ac o o 2.581
To u he alida e ou esul s om he LSM and582
Fou ie analyses, we manually inspec ed he pho ome -583
ic da a o each o he ⇠2000 as e oids. Fo each objec 584
we i s ex ac ed he calib a ed epochs and magni udes585
o each band (in ug i) and plo ed magni ude e sus586
modi ied Julian da e (MJD) o e eal aw b igh ness587
a ia ions (see Figu e 8 o an example). We hen an588
a simpli ied implemen a ion o he Mul i-band Lomb-589
Sca gle pe iodog am ha included a de e mina ion o 590
he bes - i o a ion pe iod wi hou modeling he ligh 591
cu e o measu e he i . We examined he powe s592
equency pe iodog am cu e o pinpoin he s onges 593
peak and con e ed he equency associa ed wi h ha 594
s onges peak in o he o a ion pe iod, doubling he595
esul o accoun o elonga ed as e oid shapes ha yp-596
ically esul in double-peaked ligh cu es. Folding he597
obse a ions on his pe iod, wi h small e ical o↵se s598
being adjus ed pe band, p oduced phase- olded ligh 599
cu es, which we inspec ed by eye o con i m a cohe en 600
ampli ude and shape. Those objec s wi h eliable ligh 601
cu e shapes, ampli udes, and compu ed o a ion pe i-602
ods we e no ed o u he compa ison wi h he esul s603
om he modeled Mul i-band Lomb-Sca gle and Fou ie 604
analyses, pa icula ly no ing he pa ame e s ha likely605
led o poo o a ion pe iod de e mina ion.606
Figu e 8. Magni ude o e ime o Rubin Fi s Look So-
la Sys em objec disco e y, 2025 MM81, bo h o he ull
obse a ion pe iod ( op) and zoomed-in on a single nigh
(bo om) o see he magni ude a ia ion. Obse a ions we e
aken in g-, -, and i-band; he numbe o obse a ions in
each band is shown in he legend. The magni ude a ia-
ion, i s ex en ('1.2 magni udes), he objec ’s o a ion
pe iod ('0.045 days = '1.1 h ), and e en i s colo s (e.g.,
g '0.6) can be de e mined di ec ly om he aw pho-
ome y om a single nigh o obse a ions.
As a esul , his addi ional s ep was p ima ily use ul607
o de e mining ou eliabili y h eshold o he com-608
pu ed o a ion pe iods. .30 obse a ions in wo bands609
2025 MM81
Da a P e iew 1
•ComCam (1 a , 9/189 LSSTCam de ec o s), 159 ames (g iz) in
low eclip ic la i ude ield, spanning 30 nigh s.!
•~6000 de ec ions o >400 as e oids.!
•Pho ome y and Images! We a e ge ing amilia wi h Rubin da a
and he RSP.!
•Sea ch o ac i e objec s, e.g Rubin Come Ca che s (Chandle
e al.) and wo k by o he s.
NSF-DOE Ve a C. Rubin Obse a o y
3I in Rubin Da a
•~10 Rubin coinciden obse a ions o 3I/
ATLAS!
•Follow-up obse a ions, including ToO
es ing!
•Commissioning lessons!
•Collabo a ion (>300 au ho s) wi h!
•Rubin P ojec incl. Commissioning!
•LSST SSSC!
•Rubin Builde s
8
aa2025-06-212025-06-21 bb2025-06-222025-06-22 cc2025-06-222025-06-22
dd2025-06-302025-06-30 ee2025-06-302025-06-30 2025-07-022025-07-02
gg2025-07-022025-07-02 hh2025-07-022025-07-02 ii2025-07-022025-07-02
Figu e 2. Galle y o se endipi ous obse a ions o 3I/ATLAS om he NSF-DOE Ve a C. Rubin Obse a o y (si e code X05).
All images a e 3000 ⇥3000 and ha e been ep ojec ed so ha No h appea s up, and Eas o he le . The an i-sola (yellow,
black-ou lined a ow) and an i-mo ion (black, ed-ou lined a ow) di ec ions a e indica ed. All da es and imes a e TAI. (a)
2025 June 21 08:11:32. (b) 2025 June 22 02:32:47. An a ea o oughly e ical sa u a ion masking can be seen nea he cen e
o he ame; 3I/ATLAS is no wi hin he masking, bu he nea by blended s a is. (c) 2025 June 22 03:07:49. (d) 2025 June
30 02:25:46. 3I/ATLAS is in on o a sa u a ed s a . (e) 2025 June 30 02:26:26. 3I/ATLAS is adjacen o he sa u a ed s a
a he cen e . ( ) 2025 July 02 00:44:25. (g) 2025 July 02 01:20:33. (h) 2025 July 02 02:31:16. (i) 2025 July 02 03:33:02.
Rubin Come Ca che s
•h ps://come ca che s.ne !
•Find come s and o he ac i e bodies!
•Fi s Rubin Ci Sci P ojec !!
•P ima ily DP1 o now!
•2,000 olun ee s!
•1.3 million classi ica ions!
•Colin O. Chandle , NSF/DOE/Rubin/
UW/NASA/…
ANTARES Communi y Fil e
•Call o Inpu on Communi y
Ale Fil e s o ANTARES
B oke !
•Fil e selec ed: "Ac i i y om
Sola Sys em objec s wi h >1
mag b igh ening/ ading om
geome y-co ec ed a e age
mag o e las 5 - 10 isi s"!
•De elopmen plans a e
pending: Adle /SNAPS/o he ?
O he Publica ions
Rubin LSST Sola Sys em P edic ions
Focus on Rubin LSST Sola Sys em Analysis So wa e
Open
Focus
Issues:
An Ex emely Deep Rubin Su ey o Explo e he
Ex ended Kuipe Bel and Iden i y Objec s
Obse able by New Ho izons, Ka elaa s e al. 2025
The Paloma wiligh su ey o ‘Ayló’chaxnim,
A i as, and come s, Bolin e al. 2025
How much ea lie would LSST ha e
disco e ed cu en ly known long-pe iod
come s? Inno e al. 2025
P edic ions o he LSST Sola Sys em Yield:
Disco e y Ra es and Cha ac e iza ions o Cen au s,
Mu agh e al. 2025
The Visibili y o he Ō au ahi–Ox o d In e s ella
Objec Popula ion Model in LSST, Do sey e al. 2025
F om a Diffe en S a : 3I/ATLAS in he Con ex o he
Ō au ahi–Ox o d In e s ella Objec Popula ion Model,
Hopkins e al. 2025
P edic ions o Spa se Pho ome y o Jupi e - amily Come Nuclei in he LSST E a, Donaldson e al. 2024
