The AsterNym star registry
Uñallamacha
Uñallamacha: the blue-white star of Scorpius
blue-white · Scorpius · HD 155985
Uñallamacha is a blue-white star, the colour of the hottest, youngest suns in the constellation Scorpius, one of the stars with a proper name recognised in the IAU Catalog of Star Names. At magnitude 6.49 it is visible to the naked eye under a dark sky.
Most stars in the sky are anonymous points of light. Uñallamacha is not. Some IAU-recognised names are ancient; others were adopted by the IAU only recently. Either way, the star already has a scientific identity, and a dedication attaches a human story to it.
Real star · Personal dedication · Recorded in the AsterNym registry
See what a dedicated page looks like: preview
Uñallamacha at a glance
- Constellation
- Scorpius
- Other name
- HD 155985
- Catalogue number
- HIP 84556
- Distance
- ≈ 3,639 light-years
- Brightness
- Magnitude 6.49 naked-eye
- Star type
- B0.5Ib
- Colour
- blue-white
- Best seen from
- The Southern Hemisphere and lower northern latitudes
- Right ascension
- 17h 17m 06s
- Declination
- −44° 46′ 43″
J2000 catalogue coordinates that can be independently cross-checked against astronomical databases. A planetarium app showing coordinates of date will differ slightly, because proper motion and precession move a star’s apparent position over time.
What kind of star is Uñallamacha?
Uñallamacha is a blue-white supergiant. Its surface runs somewhere between 10,000 and 30,000°C, which is what gives it a blue-white cast. Colour in a star is a temperature reading rather than a decoration: the hot ones are blue and the cool ones red, the opposite way round to a kitchen tap.
Its colour is not the whole story. A blue-white star still in the steady part of its life would burn for tens of millions of years. This one is past that stage, and it is cool at the surface because it has swollen outward, not because it was born this way.
It is a supergiant, which means it has left the stable part of its life and swollen enormously. Put it where the Sun is and its surface would swallow the inner planets. Stars this size do not fade quietly; this one will end as a supernova, and on a human timescale that could be tonight or in a million years.
Uñallamacha barely moves against the background sky, which is mostly a statement about how far away it is. For every practical purpose, including yours, it is fixed.
The light you are looking at is old
Uñallamacha is about 3,639 light years away, so the light reaching you now set out around -1613. You are not looking at the star as it is. You are looking at the star as it was, and there is no way to see it any other way.
That delay is the part people find hardest and like most. A star is the one thing you can give someone that was already old before either of you was born and will outlast anything else you could have chosen.
It sits at the edge of what an unaided eye can do, so finding it is a deliberate act rather than an accident.
What could a Uñallamacha dedication represent?
Uñallamacha is especially meaningful for someone who:
- · Deserves something older than any gift shop
- · Marks a beginning, an anniversary or a promise
- · Is remembered every time you look up
- · Has a light you want recorded somewhere permanent
Dedication idea
“For the one I think of when I find Scorpius in the sky.”
Where can you see Uñallamacha?
It is easy to see from much of the Southern Hemisphere. It can also appear from lower northern latitudes, but it never rises for observers north of about latitude 45°N. It passes directly overhead at latitude 45°S. It stands highest at midnight in June, so June and July evenings are the best time to look. At magnitude 6.49 it is a naked-eye star only under a dark sky, binoculars make it certain.
Uñallamacha belongs to Scorpius.
What does Uñallamacha mean in astrology?
The classical fixed-star tradition: Ptolemy, the medieval Behenian lists, Robson’s 1923 compilation. Is silent on Uñallamacha, and we don’t invent lore where none exists. What astrology can still read is the star’s real position, below.
Projected onto the zodiac the way fixed-star astrology reads any star, Uñallamacha stands at 21° Sagittarius at the J2000 epoch, and the Sun passes that degree around 11 December in the years around 2000. Fixed-star longitude shifts slowly against the tropical zodiac because of precession, about one degree every seventy-two years, so a natal conjunction must be calculated for the birth year rather than read off this J2000 value or a calendar date.
Traditional interpretations, not facts or predictions. The position and dates are computed.
Dedicate Uñallamacha to someone who matters
A flower fades. A card is eventually put away. A star gives your message a place in the sky.
from$29.95a year
Dedicate Uñallamacha →Real star · your message · a page to share
Your Uñallamacha dedication includes
- Your chosen dedication name
- Your personal message
- Uñallamacha's real astronomical coordinates
- A shareable dedication page
- Its location on the AsterNym Galaxy Map
- An optional printable certificate and gift presentation
Uñallamacha keeps its established astronomical name. Your dedication is a personal commemorative record within the AsterNym registry.
Frequently asked questions about Uñallamacha
- What does Uñallamacha mean in astrology?
- The classical fixed-star tradition has no documented meaning for Uñallamacha. Projected onto the zodiac, Uñallamacha stands at 21° Sagittarius, and the Sun passes that degree each year around 11 December.
- Is Uñallamacha the brightest star?
- Uñallamacha shines at magnitude 6.49 · visible to the naked eye on a clear night, one of the few thousand stars with an officially recognised name.
- How far away is Uñallamacha?
- Uñallamacha is approximately 3,639 light-years from Earth. The light reaching us tonight began its journey around 3,639 years ago.
- Which constellation contains Uñallamacha?
- Uñallamacha is part of Scorpius.
- Can everyone see Uñallamacha?
- It is easy to see from much of the Southern Hemisphere. It can also appear from lower northern latitudes, but it never rises for observers north of about latitude 45°N. It passes directly overhead at latitude 45°S. It stands highest at midnight in June, so June and July evenings are the best time to look. At magnitude 6.49 it is a naked-eye star only under a dark sky, binoculars make it certain.
- Is dedicating Uñallamacha an official astronomical renaming?
- No. Uñallamacha keeps its internationally recognised astronomical name. An AsterNym dedication records your personal name and message in the AsterNym registry without changing the star's scientific identity.
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