Key parameters at a glance
- A radius of 4.42 Earth radii
- A mass of 17.90 Earth masses
- Surface gravity around 0.92 g
- An orbital period of 95.233 days
- Distance from Earth 59.37 light-years
- Earth Similarity Index 0.513
- Travel time at Voyager 1 speed 1,047,039 years
1 sibling around HD 99492
HD 99492 c shares its host star with 1 other confirmed planet. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| HD 99492 b | Neptune-like | 5.44 | 25.50 | 17.050 | — | 2004 |
| HD 99492 c this | Neptune-like | 4.42 | 17.90 | 95.233 | — | 2023 |
HD 99492 c Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#472of 574
top 82.1%
This planet
4.42R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | HD 99492 c | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 4.42 | 11.21 |
| Mass (M⊕) | 1.00 | 17.90 | 317.83 |
| Density (g/cm³) | 5.51 | 1.14 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.92 | 2.53 |
| Insolation (S⊕) | 1.00 | — | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Minimum mass (M sin i) | 17.900 M⊕ | Lower bound from radial-velocity fitting. |
Star Catalogue Identifiers
HD
HD 99492
HIP
HIP 55848
TIC
TIC 363549734
Gaia DR2
Gaia DR2 3812355294261019904
Gaia DR3
Gaia DR3 3812355294262255104
System
HD 99492
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 95.23 Earth days (26.1% of a terrestrial year) on a nearly circular orbit.
Eq. Temperature
—
Insolation (S⊕)
—
Earth = 1.00
Earth Similarity (ESI)
0.513
0 = alien, 1 = Earth-identical
Discovery Paper
Primary reference
Stalport et al. 2023Instrument
HARPS-N Spectrograph
Publication
2023-08
Observation locale
Ground
Discovery cohort
Planets confirmed in 2023 at Roque de los Muchachos Observatory (7 shown).
Host System: HD 99492
Spectral Class
K-type orange
Effective Temperature
4,929 K — cooler than the Sun (5,778 K)
Estimated Age
4.80 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.823 R☉
Stellar Mass
0.850 M☉
Metallicity [Fe/H]
0.30
Extended Stellar Properties
Surface gravity (log g)
4.570 dex
Stellar density
2.837 g/cm³
Systemic radial velocity
3.10 km/s
Rotational v·sin i
0.41 km/s
Activity index (log R'HK)
-4.930
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 12 bands
Astrometric Data
Parallax
54.906 mas
Total Proper Motion
752.283 mas/yr
PM Right Ascension
-728.28 mas/yr
PM Declination
188.53 mas/yr
Galactic Cartesian (pc)
x = -0.988 · y = 0.144 · z = 0.052
Equatorial (J2000)
RA 171.68969° · Dec 3.00713°
Galactic ℓ, b
259.274° · 58.507°
Ecliptic λ, β
171.178° · -0.532°
HTM-20 index
1625330463
Observation Record
Photometric series
1
RV measurements
2
Stellar spectra
3
Archive notes
4
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