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Theta Ursae Majoris — Star in Ursa Major

Magnitude 3.2m Star Ursa Major (UMa) Visible
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1Physical Properties

Magnitude 3.17
Spectral Type F7V
Star Color Yellow (B-V 0.46)
Distance 44 ly

2Position & Identifiers

RA 09h 32m 51.4s
Dec +51° 40' 38.0"
Constellation Ursa Major (UMa)
HR 3775
HIP 46853
HD 82328
SAO 27289
Bayer Theta
Flamsteed 25 UMa
Double Cat 7420
SIMBAD

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Easy Easy Medium+
50mm finder Easy Easy Easy
150mm scope Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

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Best season Jan – Mar (peak: Feb)

5Survey Image

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7

Size Comparison

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8

Compare Stars

9

Spectral Classification

10

Hertzsprung-Russell Diagram

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Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
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

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15Stellar Notes

CPM.
371.0d, K 4.3k/s, V0 +13.0k/s, asini 21.24. Orbit questioned by Morbey and Griffin (1987, ApJ, 317, 343). | Unresolved by speckle interferometry.
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.

NGC 2841
Easy
Bright spiral galaxy
Galaxy mag 9.3 1.8° Ursa Major
Show on Map

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