About Baten Kaitos
Description
Baten Kaitos, Zeta Ceti, is a K-type giant of spectral class K0 III about 235 light-years away in the belly of the celestial whale. It shines at magnitude 3.73. Baten Kaitos is a slightly evolved red-clump giant with a mass of about 2.5 Suns.
Observing Tips
Baten Kaitos sits in the southern part of Cetus, between Diphda (Beta Ceti) to the south and Menkar (Alpha Ceti) to the north. It appears in binoculars as a warm amber point. Best observed October through February.
History
The name Baten Kaitos comes from the Arabic "baṭn al-qayṭas," meaning "the belly of the sea-monster." The IAU adopted the name in 2016.
Fun Facts
Baten Kaitos has a surprisingly large proper motion — it moves across the sky at about 0.25 arcseconds per year, noticeable over a century of careful astrometric measurement. The motion reflects the star's moderate space velocity through the galactic disk.
Observe
1Physical Properties
2Position & Identifiers
3How easy to spot?
| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Medium+ | Medium+ |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
5Survey Image
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Explore
7
Size Comparison
8
Compare Stars
9
Spectral Classification
10
Hertzsprung-Russell Diagram
11
Stellar Lifecycle
12
Blackbody Spectrum
13
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
14
Stellar Fusion
Discover
15Stellar Notes
16
Light Travel Time Machine
17
Relativistic Travel
Nearby in the Sky
Other targets within a few degrees — pan your scope a little and keep exploring.
Visibility scores assume a 150 mm Newton at Bortle 4.
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