Planet sig Ori IRS 1 b

Detailed information about planet sig Ori IRS 1 b and its parameters.

Planet parameters Publications Observability Predictor

Planet

Name

sig Ori IRS 1 b

Planet Status

Confirmed

Discovered in

2009

Publication Status

Published in a refereed paper

Update

2025-09-01

Mass

50.0

M_J 1 publication

σ Orionis IRS1 A and B: A Binary Containing a Proplyd

Mass*sin(i)

—

Semi-Major Axis

105.0 AU 2 publications

σ Orionis IRS1 A and B: A Binary Containing a Proplyd
A deep look into the cores of young clusters. I. σ-Orionis

Orbital Period

—

Eccentricity

—

Angular distance

0.25

arcsec

ω

—

T_peri

—

Radius

13.7

R_J

Inclination

—

Detection Method

Imaging

Mass Meas. Method

Spectrum

Radius Meas. Method

—

Primary transit

—

Secondary transit

—

λ

—

Impact Parameter b

—

Time V_r=0

—

Velocity Semiamplitude K

—

Calculated temperature

2795.0 (\begin{matrix} + 205.0 \\ - 395.0 \end{matrix})

K 1 publication

σ Orionis IRS1 A and B: A Binary Containing a Proplyd

Measured temperature

—

Hottest point longitude

—

Geometric albedo

—

Surface gravity log(g/g_H)

—

Alternate Names

[BHM2009] SigOri-MAD-8

Data Source	Type	Result Value	Result Figure	Notes	Reference

Molecule	Data Source	Type	Result Value	Result Figure	Notes	Reference

Spectral type M7.5, L = 0.109 L_Sol. The brown dwarf lies 0.25 arcseconds away from the primary source (105 AUs at 420 pc) and is likely embedded in a protoplanetary disk that is being photoevaporated by the UV flux of the nearby Sigma Orionis multiple system (Hodapp et al. 2009). Along with the young age of the system, this would account for the unusually large radius of the substellar object calculated through the Stefan-Boltzmann constant formula.

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Star

Name

sig Ori IRS1

Distance

420.0 pc 1 publication

σ Orionis IRS1 A and B: A Binary Containing a Proplyd

Spectral type

M1V

Apparent magnitude V

—

Apparent magnitude I

—

Apparent magnitude J

—

Apparent magnitude H

—

Apparent magnitude K

—

Mass

0.55 (\pm 0.25)

M_Sun 1 publication

σ Orionis IRS1 A and B: A Binary Containing a Proplyd

Age

0.001 Gyr 1 publication

σ Orionis IRS1 A and B: A Binary Containing a Proplyd

Effective temperature

3705.0 (\pm 150.0)

K 1 publication

σ Orionis IRS1 A and B: A Binary Containing a Proplyd

Radius

2.25 R_Sun

Metallicity [Fe/H]

—

Detected Disc

IR Excess

Magnetic Field

—

RA₂₀₀₀

05:38:44.9

Dec₂₀₀₀

-02:35:57.0

Alternate Names

[BHM2009] SigOri-MAD-9

The source is 3.85 arcseconds away from Sigma Orionis multiple system, which translates into a separation of 1617 AUs if both located at 420 pc and gravitationally bound.
Hodapp et al. (2009) reckon the protostar truly tied to Sigma Orionis triple system whose total luminosity exceeding the 50,000 L_Sol would explain the proplyd photoevaporation in sig Ori IRS1, since this would be receiving the same irradiation of an object located 3-4 AUs away from a Sun-like star.

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