<s>
The	O
Advanced	B-Algorithm
Camera	I-Algorithm
for	I-Algorithm
Surveys	I-Algorithm
(	O
ACS	O
)	O
is	O
a	O
third-generation	O
axial	O
instrument	O
aboard	O
the	O
Hubble	O
Space	O
Telescope	O
(	O
HST	O
)	O
.	O
</s>
<s>
It	O
was	O
launched	O
on	O
March	O
1	O
,	O
2002	O
,	O
as	O
part	O
of	O
Servicing	O
Mission	O
3B	O
(	O
STS-109	O
)	O
and	O
installed	O
in	O
HST	O
on	O
March	O
7	O
,	O
replacing	O
the	O
Faint	B-Algorithm
Object	I-Algorithm
Camera	I-Algorithm
(	O
FOC	B-Algorithm
)	O
,	O
the	O
last	O
original	O
instrument	O
.	O
</s>
<s>
It	O
offered	O
several	O
important	O
advantages	O
over	O
other	O
HST	O
instruments	O
:	O
three	O
independent	O
,	O
high-resolution	O
channels	O
covering	O
the	O
ultraviolet	B-Application
to	O
the	O
near-infrared	O
regions	O
of	O
the	O
spectrum	O
,	O
a	O
large	O
detector	O
area	O
and	O
quantum	O
efficiency	O
,	O
resulting	O
in	O
an	O
increase	O
in	O
HST	O
's	O
discovery	O
efficiency	O
by	O
a	O
factor	O
of	O
ten	O
,	O
a	O
rich	O
complement	O
of	O
filters	O
,	O
and	O
coronagraphic	O
,	O
polarimetric	O
,	O
and	O
grism	O
capabilities	O
.	O
</s>
<s>
The	O
observations	O
undertaken	O
with	O
ACS	O
provided	O
astronomers	O
with	O
a	O
view	O
of	O
the	O
Universe	O
with	O
uniquely	O
high	O
sensitivity	O
,	O
as	O
exemplified	O
by	O
the	O
Hubble	O
Ultra-Deep	O
Field	O
,	O
and	O
encompass	O
a	O
wide	O
range	O
of	O
astronomical	O
phenomena	O
,	O
from	O
comets	O
and	O
planets	O
in	O
the	O
Solar	O
System	O
to	O
the	O
most	O
distant	O
quasars	B-Application
known	O
.	O
</s>
<s>
Its	O
detector	O
consists	O
of	O
two	O
butted	O
2048x4096	O
,	O
15µm/pixel	O
charge-coupled	B-Algorithm
devices	I-Algorithm
(	O
CCDs	O
)	O
for	O
a	O
total	O
of	O
16	O
megapixels	O
manufactured	O
by	O
Scientific	O
Imaging	O
Technologies	O
(	O
SITe	O
)	O
.	O
</s>
<s>
This	O
detector	O
was	O
also	O
significantly	O
more	O
sensitive	O
than	O
the	O
WFC	O
at	O
near-ultraviolet	O
wavelengths	O
(	O
<3	O
50nm	O
)	O
.	O
</s>
<s>
The	O
first	O
spot	O
was	O
the	O
most	O
popular	O
of	O
the	O
two	O
,	O
for	O
example	O
,	O
for	O
imaging	O
circumstellar	O
disks	O
around	O
nearby	O
bright	O
stars	O
or	O
the	O
host	O
galaxies	O
of	O
luminous	O
quasars	B-Application
.	O
</s>
<s>
The	O
Multi	O
Anode	O
Microchannel	O
Array	O
(	O
MAMA	O
)	O
of	O
the	O
SBC	O
is	O
a	O
low-background	O
photon-counting	O
device	O
optimized	O
for	O
the	O
ultraviolet	B-Application
in	O
the	O
wavelength	O
range	O
of	O
115	O
–	O
170nm	O
.	O
</s>
<s>
The	O
ACS	O
SBC	O
is	O
in	O
fact	O
a	O
flight	O
spare	O
from	O
the	O
Space	B-Algorithm
Telescope	I-Algorithm
Imaging	I-Algorithm
Spectrograph	I-Algorithm
(	O
STIS	B-Algorithm
)	O
.	O
</s>
<s>
The	O
HRC	O
and	O
WFC	O
elements	O
consist	O
of	O
eleven	O
broad-band	O
filters	O
,	O
one	O
medium-band	O
filter	O
,	O
five	O
narrow-band	O
filters	O
,	O
three	O
visible	O
and	O
three	O
ultraviolet	B-Application
polarizers	O
,	O
one	O
prism	O
for	O
the	O
HRC	O
,	O
and	O
one	O
grism	O
(	O
580	O
–	O
1100nm	O
)	O
.	O
</s>
<s>
Four	O
of	O
the	O
filters	O
have	O
bandpasses	O
in	O
the	O
near-ultraviolet	O
and	O
so	O
can	O
be	O
used	O
with	O
the	O
HRC	O
only	O
.	O
</s>
