Pi4 Orionis

{{Short description|Binary star system in the constellation Orion}}

{{Starbox begin

| name=π⁴ Orionis

}}

{{Starbox image

| image=

{{Location mark

|image=Orion constellation map.svg|alt=|float=center|width=280

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=π⁴ Orionis

|x=888|y=360

}}

|caption=Location of π⁴ Orionis (circled)

}}

{{Starbox observe

| epoch = J2000.0

| equinox = J2000.0 (ICRS)

| constell = Orion

| ra = {{RA|04|51|12.36472}}

| dec = {{DEC|+05|36|18.3723}}

| appmag_v = 3.685

}}

{{Starbox character

| class = B2 III

| u-b = −0.797

| b-v = −0.180

| r-i =

}}

{{Starbox astrometry

| radial_v = 23.3

| prop_mo_ra = −2.21

| prop_mo_dec = +0.85

| parallax = 3.10

| p_error = 0.18

| parallax_footnote =

| absmag_v =

}}

{{Starbox orbit

| reference =

| period_unitless = 9.5191 d

| eccentricity = 0.03

| periastron = {{Val|2418275.65|10.0|fmt=commas}}

| periarg = 165

| k1 = 25.8

}}

{{Starbox detail

| component1 = π⁴ Ori A

| mass = {{Val|10.95|0.97}}

| radius = 9.1

| luminosity = 19,726

| temperature = {{Val|21874|126|fmt=commas}}

| gravity = 3.59

| metal_fe = −0.31

| rotational_velocity = 38

| rotation =

| age_myr = {{Val|15.4|1.0}}

}}

{{Starbox catalog

| names = π⁴ Ori, 3 Orionis, BD+05°745, FK5 179, HD 30836, HIP 22549, HR 1552, SAO 112142

}}

{{Starbox reference

| Simbad = 3+Ori

}}

Pi⁴ Orionis (π⁴ Ori, π⁴ Orionis) is a binary star system in the western part of the Orion constellation. It is visible to the naked eye with an apparent visual magnitude of 3.7. Based upon an annual parallax shift of 3.1 mass, it is located roughly 1,050 light-years from the Sun.

This is a spectroscopic binary star system with an orbital period of 9.5 days and an eccentricity of 0.03. The primary component is a B-type star with a stellar classification of B2 III. The stellar spectrum of π⁴ Ori A shows a strong depletion of the element boron. It has nearly 11 times the mass of the Sun and nine times the Sun's radius. The star is 15.4 million years old and has a projected rotational velocity of 38 km/s. It shines with 19,726 times the solar luminosity from its outer atmosphere at an effective temperature of {{Val|21874|fmt=commas|ul=K}}.

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