Key parameters at a glance

A radius of 12.90 Earth radii
A mass of 1,484.27 Earth masses
Surface gravity around 8.92 g
An orbital period of 264.150 days
Semi-major axis 0.8500 AU
Distance from Earth 111.18 light-years
Earth Similarity Index 0.426
Travel time at Voyager 1 speed 1,960,677 years

Context from the literature

HD 40979 b is an extrasolar planet orbiting the star HD 40979, was detected from the Lick and Keck observatories and photometric observations at Fairborn Observatory reveal low-amplitude brightness variations in HD 40979. It is thought to be a large gas giant planet. It was discovered in 2002 by Debra Fischer.

Excerpted from Wikipedia · full article

HD 40979 b Planet Profile

Physical Specs

Radius

12.90 R⊕

Radius (Jupiter)

1.150 R♃

Mass

1,484.27 M⊕

Mass (Jupiter)

4.670 M♃

Density

3.80 g/cm³

Surface Gravity

8.92 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.426

HZ Position Unknown

Controversial No

Discovery

Year 2002

Method Radial Velocity

Facility Multiple Observatories

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#1011of 1771

top 57.0%

This planet

12.90R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

HD 55696 b 12.90 R⊕ HD 24040 b 12.90 R⊕ BD-210397 c 12.90 R⊕

Metric	Earth	HD 40979 b	Jupiter
Radius (R⊕)	1.00	12.90	11.21
Mass (M⊕)	1.00	1,484.27	317.83
Density (g/cm³)	5.51	3.80	1.33
Surface Gravity (g)	1.00	8.92	2.53
Insolation (S⊕)	1.00	—	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Minimum mass (M sin i)	1,484.266 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

HD 40979

HIP

HIP 28767

TIC

TIC 440489582

Gaia DR2

Gaia DR2 961428192989499904

Gaia DR3

Gaia DR3 961428192989499904

System

HD 40979

Percentile among Gas Giant cohort

Radius 12.900 R⊕ · percentile 41 / cohort 1771

Mass 1,484.266 M⊕ · percentile 74 / cohort 1747

Orbital period 264.15 d · percentile 59 / cohort 1533

Distance 34.09 pc · percentile 10 / cohort 1759

ESI 0.426 · percentile 93 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

264.150 days

Semi-major axis

0.8500 AU

Eccentricity

0.250

Inclination

— °

Year Length

A year here lasts approximately 264.15 Earth days (72.3% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 0.8500 AU.

Extended Orbital Architecture

RV semi-amplitude (K)

119.400 m/s

Transit mid-time (BJD)

2,452,405.1000

Long. of periastron (ω)

323.40°

Angular separation (arcsec)

24.90000

Eq. Temperature

—

Insolation (S⊕)

—

Earth = 1.00

Earth Similarity (ESI)

0.426

0 = alien, 1 = Earth-identical

Discovery Paper

Primary reference

Fischer et al. 2003

Instrument

Multiple Instruments

Publication

2003-04

Observation locale

Ground

Discovery cohort

Planets confirmed in 2002 at Multiple Observatories (2 shown).

HD 12661 c · Gas Giant HD 83443 b · Gas Giant

Host System: HD 40979

Spectral Class

F-type yellow-white

Effective Temperature

6,165 K — hotter than the Sun (5,778 K)

Estimated Age

3.56 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.210 R☉

Stellar Mass

1.450 M☉

Metallicity [Fe/H]

0.20

Extended Stellar Properties

Surface gravity (log g)

4.430 dex

Stellar density

0.868 g/cm³

Systemic radial velocity

32.80 km/s

Rotational v·sin i

7.40 km/s

Activity index (log R'HK)

-4.630

Metallicity ratio

[Fe/H]

Distance

34.09 parsec

Light-years 111.18 ly

V-band magnitude

6.76 mag

Voyager-speed travel 1,960,677 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

29.307 mas

Total Proper Motion

180.123 mas/yr

PM Right Ascension

95.21 mas/yr

PM Declination

-152.90 mas/yr

Galactic Cartesian (pc)

x = -0.014 · y = 0.716 · z = 0.698

Equatorial (J2000)

RA 91.12533° · Dec 44.25979°

Galactic ℓ, b

168.496° · 10.872°

Ecliptic λ, β

90.858° · 20.824°

HTM-20 index

165762179

Observation Record

Photometric series

RV measurements

Stellar spectra

Archive notes

Wikipedia →