Possible Ways to Access
ANTARES
The future Large Synoptic Survey Telescope
(LSST) alert stream of detected transient ob-
jects is anticipated to amount to ten million
raw alerts per night, and we expect to have
a significant number of Principal Investiga-
tor programs following up on these events
with Gemini (both South and North). A key
to handling such a massive influx of tran-
sient events is to filter the stream down to
a quantity and science focus appropriate for
an individual program.
The first step in that process will be done by
“event brokers.” These automated software
systems will sift through, characterize, anno-
tate, and prioritize events for follow up. The
LSST project is planning to provide only a very
simple filtering system, or mini-broker, how-
ever, so any work on catalog matching or clas-
sification must be done by the community.
One example of a community broker is the
Arizona-NOAO Temporal Analysis and Re-
sponse to Events System (ANTARES) — a
joint project of the National Optical As-
tronomy Observatory and the Department
of Computer Science at the University of
Arizona. The follow-up System that is cur-
rently taking shape will begin with ANTAR-
ES, which will attempt to classify events by
cross-matching them with existing catalogs
and by identifying light-curve shapes. Users
will be able to define filters to select objects
of interest.
The resulting more bespoke, but still large,
streams will be evaluated by program-spe-
cific software, which will provide another
level of filtering and generate actual re-
quests for observations on the system tele-
scopes. ANTARES itself is being prepared
for testing with the Zwicky Transient Facility
(ZTF) public survey alerts, and NOAO has ad-
vertised limited, shared-risk, capabilities via
the NOAO call for 2018B. The intention is to
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GeminiFocus
see how it goes, then reassess for a wider
call in 2019A.
In the future, and in particular when LSST is
operating, how will the Gemini community
access ANTARES? There are two possible
routes: first, once ANTARES reaches steady-
state, NOAO expects to make it available
as a standalone facility to all astronomers
(perhaps limited by resource and/or per-
formance considerations); second, because
Gemini will be a member of the wider fol-
low-up system (including at least ANTARES,
Las Cumbres Observatory, Southern Astro-
physical Research Telescope, and Gemini),
it should be possible for the communities
of all these facilities to prepare proposals
which require multiple facilities in the net-
work.
We are in the early stages of developing
concepts to realize this. Check back here
for more information as plans develop over
the coming two years, but the takeaway
message is that ANTARES feeds should be
available to the Gemini community once
LSST is operating.
Gemini’s Cloudcams
One of the benefits of observing at a tele-
scope site is that, in the case of iffy weather,
one can “pop outside the dome” and quick-
ly (dark adaptation allowing) see what the
sky is doing. So when Gemini relocated as-
tronomers from the summit to base facility
operations (at the end of 2015 at Gemini
North; end of 2016 at Gemini South) we
were keen to ensure that our observers
would be able to gauge the sky.
For some years, the Canada-France-Hawai‘i
telescope has been operating “cloudcams”
— small and sensitive commercial cameras
capable of long exposures — to provide
current time-lapse photography of parts of
the sky over Maunakea.
January 2019 / 2018 Year in Review