Tau Leonis
Star in the constellation Leo
title: "Tau Leonis" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["g-type-giants", "bayer-objects", "leo-(constellation)", "durchmusterung-objects", "flamsteed-objects", "henry-draper-catalogue-objects", "hipparcos-objects", "bright-star-catalogue-objects"] description: "Star in the constellation Leo" topic_path: "general/g-type-giants" source: "https://en.wikipedia.org/wiki/Tau_Leonis" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary Star in the constellation Leo ::
| name=τ Leonis | image = |image=Leo IAU.svg|alt=|float=center|width=280 |label=|position=right |mark=Red circle.svg|mark_width=10|mark_link=τ Leonis |x=285|y=705 | caption = Location of τ Leonis (circled in red) | constell = Leo | epoch = J2000.0 (ICRS) | ra = | dec = | appmag_v = 5.00 | class = G8- IIIa | b-v = +1.005 | u-b = +0.80 | variable = | radial_v = −8.90 | prop_mo_ra = +16.89 | prop_mo_dec = −9.81 | parallax = 5.80 | p_error = 0.33 | parallax_footnote = | absmag_v = | mass = | radius = | luminosity = | temperature = | metal_fe = | gravity = | rotational_velocity = | age_myr = | names = τ Leo, 84 Leo, BD+03°2504, FK5 1297, HD 99648, HIP 55945, HR 4418, SAO 118875 |Simbad=tau+Leo
Tau Leonis (τ Leo) is a star in the zodiac constellation of Leo. Because it is located near the ecliptic, it is subject to occultations by the Moon. It has an apparent visual magnitude of 5.00, which is bright enough to be seen with the naked eye. The distance to this star, as estimated using parallax measurements, is 560 light years. It is moving closer to the Sun with a radial velocity of −9 km/s.
This G-type giant star has a stellar classification of G8- IIIa and currently resides on the red giant branch. It has about 390% of the Sun's mass. The star is much younger than the Sun, with an age of around 190 million years. As an evolved giant, it has expanded to about 25 times the Sun's radius and radiates 330 times the luminosity of the Sun. The effective temperature of the outer atmosphere is 4,910 K.
References
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| title=* tau Leo | accessdate=2016-09-29 | postscript=. }}
::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::