Key facts
- Category
- Stars
- Object class
- K-type main-sequence star
- Mass
- ~0.70 solar masses
- Temperature
- ~4,545 K surface
- Scale fact
- 925,000 kmdiameter
- Estimated age
- ~6 billion years
- Composition
- Hydrogen and helium
61 Cygni A
925,000 kmdiameter
Visual creditscaleofspace.org / CC BY-NC 4.0
Details
61 Cygni A is a nearby orange dwarf star in one of the sky’s most famous binary systems. The 61 Cygni pair became the first stellar system with a measured parallax, and 61 Cygni A is also a standard reference star for the K5 V spectral class.
61 Cygni A is the brighter member of a nearby binary of orange dwarf stars. In 1838 Friedrich Bessel measured the pair’s annual parallax, producing the first widely accepted distance to a star beyond the Sun.
The star is smaller, cooler and less massive than the Sun. Its historical importance came from its proximity and large motion across the sky, which made the tiny geometric shift caused by Earth’s orbit easier to measure.
Links
- Editorial guides
- Universe journey
- Solar neighborhood
- Preset views
- Wikipedia
- 61 Cygni A on Wikipedia
Size neighbors
Objects near 61 Cygni A on the scale
On the logarithmic size axis, 61 Cygni A falls between Lalande 21185 and Sun. The band uses nearby Stars records.
Shared physical scale
2.17million km
Sources
References for 61 Cygni A
Measurements and descriptive context are compiled by the Scale of Space team from the references below. If you find an error, please let us know.
- 61 Cygni A — Wikipedia
- Visual: scaleofspace.org / CC BY-NC 4.0
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About
Scale of Space is a scroll-based journey through the universe, placing objects on a single logarithmic scale so you can compare size across an unbroken range.
Guides explain selected parts of that range, while focused views filter the objects by subject.