CC Cir

STARWN8(h) Wolf-Rayet star

ILLUSTRATION FROM SPECTRAL TYPE WN8(h) · 40 000 K · 0.99 L☉ · VARIABLE, MAG 11.24–11.42 · PERIOD 0.146 DAYS · PULSE COMPRESSED

[

OVERVIEW

] STAR

CC Cir is a WN8(h) Wolf-Rayet star in the constellation Circinus, 644.6 from Earth, shining at apparent magnitude 11.34 (). It is catalogued as HD 134877 and HIP 74634.

WHAT IT IS
Wolf-Rayet star
HOW FAR
644.6

The light arriving now left it that long ago.

HOW BRIGHT (V)

A small telescope reaches it.

WHERE TO LOOK
Circinus

The patch of sky it sits in, as seen from Earth.

[

THE MODEL

] RADIUS FROM THE LUMINOSITY AND THE TEMPERATURE
OUTSIDE THE SURVEYED VOLUME · DRAG TO ORBIT

CALCULATED · NOT AN OBSERVATION · RADIUS FROM THE LUMINOSITY AND THE TEMPERATURE · SPECTRAL TYPE WN8(h) · 40 000 K · 0.99 L☉ · VARIABLE, MAG 11.24–11.42 · PERIOD 0.146 DAYS

Drawn from the radius from the luminosity and the temperature and from the same properties the picture at the top of this page uses, at the distance a flight to it would stop. Drag it, or use the arrow keys, to look from another direction. The stars behind are the 498,631 this catalogue holds real distances for, drawn from where the camera actually is — but every one of them is within 170 parsecs of the Sun and this object is much further out, so what is in the frame is that whole neighbourhood seen from outside it, piled into a knot around the Sun. The rest of the sky from here is not something this catalogue knows.

[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see CC Cir for yourself. Everything in this part of the page is worked out for a real horizon, a real night and the equipment you say you have.

TONIGHT

Say where you are, and this line says when CC Cir is worth going out for.

[

THROUGH AN EYEPIECE

] 150 MM TELESCOPE · 25 MM EYEPIECE
NE
0′ ACROSS

Out of reach of binoculars; a 150 mm telescope reaches it. Its brightest companion sits 0.40″ away, which at 48× is blended into one star.

48×
1.08
1.25
13.0
0.40 · blended into one star
APPARENT MAGNITUDE ()
11.34 · within reach

A is where the pair was the year it was measured — the ones above, in 2019, and a pair in a real orbit has moved since.

FIND IT ON THE SKY MAP ↗
[

APPARENT PLACE

] EQUINOX J2026.7

Where a telescope has to be pointed today, which is not quite where the catalogue records the object: the coordinate grid itself has turned since the year 2000 the catalogue is referred to.

RIGHT ASCENSION
DECLINATION
GRID TURNED SINCE
17.2
PROPER MOTION SINCE
0.33

Computed for 2026-08-28 00:00 UT. Two things separate it from the catalogued position above: CC Cir has moved under its own proper motion, and the coordinate grid has turned under it — about fifty arcseconds a year of precession since 2000, and the small nodding of the Earth’s axis on top of that. Aberration and refraction are not included, and neither is parallax; each is under an arcminute, which is also about as well as the catalogued position is known. The same figure for any date.

[

VARIABILITY

] WOLF-RAYET STAR WITH VARIABLE EMISSION
RANGE, AS SAMPLED
11.24 – 11.42
PERIOD
0.146 days (3.5 h)

For this class the published period is a mean cycle time rather than an ephemeris: the star repeats on that timescale without keeping to it, so counting cycles from a past event would predict a date the star has no obligation to meet.

The range is the spread the Hipparcos satellite measured, converted to the visual scale. It is approximate: the satellite sampled the star on a schedule of its own, and where a star spends little of its cycle at an extreme — the floor of an eclipse, most obviously — the sampling can miss it altogether. The classification and the period are the General Catalogue of Variable Stars’s. These elements as data.

[

DOUBLE STAR

] 1 PAIR
COMPONENTSSEPARATIONPOSITION ANGLEMAGNITUDEMEASURED
0.4″14°12.862019

Separation and position angle are as measured in the year given; a position angle is measured from north, through east. Washington Double Star Catalog 15150-5951.

[

LIFE OF THIS STAR

] STAGE 3 OF 5

CC Cir is a Wolf-Rayet star — a heavy star whose own wind has stripped its outer layers away, leaving the fusing interior bare; within about three hundred thousand years it will collapse and explode as a supernova, leaving a black hole.

  1. COLLAPSING CLOUD
    took about twenty thousand years
  2. MAIN SEQUENCE
    lasted about three million years
  3. SUPERGIANT
    about three hundred thousand years of it
    NOW
  4. SUPERNOVA
    bright for weeks, over in a second
  5. BLACK HOLE
    for the rest of time

NOW The same swelling, on a star heavy enough to keep going: helium, then carbon, then a run of heavier elements each burning faster than the last, until the core is iron and fusion can release nothing more.

NEXT The iron core collapses in about a second and the rest of the star is thrown off at a tenth of the speed of light. For a few weeks it outshines the galaxy it is in.

EVERY STAGE ON THIS TRACK
COLLAPSING CLOUDtook about twenty thousand years
A cold clump of gas and dust falls in on itself and heats as it falls. It stops being a cloud and starts being a star at the moment its core is hot enough to fuse hydrogen.
MAIN SEQUENCElasted about three million years
Hydrogen fuses to helium in the core, and the outward push of that exactly balances the star's own weight. This is the long, steady stretch — nine-tenths of a star's life — and it ends when the core's hydrogen is gone.
SUPERGIANTabout three hundred thousand years of itNOW
The same swelling, on a star heavy enough to keep going: helium, then carbon, then a run of heavier elements each burning faster than the last, until the core is iron and fusion can release nothing more.
SUPERNOVAbright for weeks, over in a second
The iron core collapses in about a second and the rest of the star is thrown off at a tenth of the speed of light. For a few weeks it outshines the galaxy it is in.
BLACK HOLEfor the rest of time
Nothing the core could be made of is stiff enough to stop the collapse, so it does not stop. What remains is a region of space that light cannot leave.
  • HOW FIRM No mass has been measured for this star, and past the main sequence its temperature no longer implies one — a red giant of one solar mass and a red supergiant of fifteen are the same colour. The figure above comes from its total output instead, and is unlikely to be better than a factor of two.
  • ALSO Its hydrogen envelope has already been driven off by its own wind, which is a late and short-lived condition and one that only the heaviest stars reach.

Which stage CC Cir is in was read from its catalogued class, its temperature and its total output at every wavelength — not from its brightness in visible light alone, which understates a cool star by a factor of several. The mass it started with is about thirty times the Sun's mass, from its luminosity, and that mass is what chooses the track. Every span of time here comes from the standard relation between a star’s mass and how long its fuel lasts, rounded to a single figure. They are orders of magnitude and none of them is a date.

[

CATALOG DATA

] 14 FIELDS

The raw catalogue values, as the source published them, with the error bars where one was published — sorted by what each set of figures is about rather than by the order they happened to be stored in.

WHAT KIND OF THING IT IS

What the object is in itself, rather than how it happens to look from here.

Spectral type
Luminosity
0.98992
Variability
Wolf-Rayet star with variable emission
Variability type ()
WR
Variability period
0.146

HOW BRIGHT IT IS

What the light adds up to, measured through one filter at a time. A magnitude is a brightness on a backwards scale — the smaller the number, the brighter the object.

Colour index (B−V)
Variable magnitude, brightest
Variable magnitude, faintest

WHERE IT IS AND HOW IT MOVES

Position, motion across the sky and the size it covers on it. These are measurements of the object as seen from here, so every one of them depends on where here is.

Proper motion (RA)
−3.58
Proper motion (Dec)
−11.72
Radial velocity
0

OTHER NAMES AND NUMBERS

The identifiers other catalogues file this object under, for anyone joining this data to theirs.

Variable-star designation
CC Cir
Washington Double Star id
15150-5951

WHERE THESE FIGURES CAME FROM

Which catalogue, paper or model each of the fields above was read from, where the source named one.

Spectral type from
SIMBAD (2006A&A...457.1015H, quality C)
[

ALSO KNOWN AS

] 3 DESIGNATIONS
  • HD HD 134877
  • HIP HIP 74634
  • Variable star CC Cir
[

LOOK IT UP ELSEWHERE

] 3 SERVICES

Each link carries the identifier printed beside it. Nothing on this page is a measurement of our own, so a number that disagrees with one of these is worth reporting — and a service that has never catalogued this object under this name will say so plainly.

[

CITE THIS PAGE

] DR1

This page is live and its numbers move when an upstream refreshes, so the citation names the release the rows belong to rather than the day you read them. The release itself is frozen, republished as a bundle, and is what a data-availability statement should point at.

PLAIN TEXT
SpaceCatalog. CC Cir [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/hd-134877
BIBTEX
@misc{spacecatalog_hd-134877,
  author       = {{SpaceCatalog}},
  title        = {{CC Cir}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/hd-134877},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from HYG Database v4.1.}
}

The values above were taken from HYG Database v4.1 — CC-BY-SA-4.0. Citing this page does not replace citing that catalogue, and its licence is share-alike: the terms reach whatever you build from these rows.

[

RELATED OBJECTS

] 8 LINKED