Pi1 Orionis

{{Starbox begin

| name = π¹ 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=π¹ Orionis

|x=860|y=232

}}

|caption=Location of π¹ Orionis (circled)

}}

{{Starbox observe

| epoch = J2000.0

| equinox = J2000.0 (ICRS)

| constell = Orion

| ra = {{RA|04|54|53.72877}}

| dec = {{DEC|+10|09|02.9952}}

| appmag_v = 4.74

}}

{{Starbox character

| class = A3 Va

| u-b = +0.09

| b-v = +0.08

| r-i =

}}

{{Starbox astrometry

| radial_v =

| prop_mo_ra = +41.49

| prop_mo_dec = −128.73

| parallax = 28.04

| p_error = 0.25

| parallax_footnote =

| absmag_v = {{val|1.71|0.09}}

}}

{{Starbox detail

| source =

| mass = {{val|1.90|0.08|0.09}}

| radius = {{val|1.73|0.13}}

| luminosity = {{val|16.91|1.42|1.29}}

| temperature = {{val|8900|131|fmt=commas}}

| gravity = {{val|4.22|0.04|0.05}}

| metal_fe = {{val|-0.12|0.14|0.16}}

| rotational_velocity = 120

| rotation =

| age_myr = 100

}}

{{Starbox catalog

| names = π¹ Ori, 7 Orionis, BD+09°683, HD 31295, HIP 22845, HR 1570, SAO 94201

}}

{{Starbox reference

|Simbad=7+Ori

}}

Pi¹ Orionis (π¹ Ori, π¹ Orionis) is a star in the equatorial constellation of Orion. It is faintly visible to the naked eye with an apparent visual magnitude of 4.74. Based upon an annual parallax shift of 28.04 mas, it is located about 116 light-years from the Sun.

This is an A-type main-sequence star with a stellar classification of A3 Va. It is a Lambda Boötis star, which means the spectrum shows lower-than-expected abundances for heavier elements. Pi¹ Orionis is a relatively young star, just 100 million years old, and is spinning fairly rapidly with a projected rotational velocity of 120 km/s. It has nearly double the mass of the Sun and 173% of the Sun's radius. The star radiates 16.9 times the solar luminosity from its outer atmosphere at an effective temperature of {{Val|8900|fmt=commas|ul=K}}.

An infrared excess indicates there is a debris disk with a temperature of 80 K orbiting {{Val|49|ul=AU}} from the star. The dust has a combined mass 2.2% that of the Earth.

References

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{{citation

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{{cite simbad

| title=* pi.01 Ori

| access-date=2016-11-15 | postscript=. }}

}}

Category:A-type main-sequence stars

Category:Orion (constellation)

Category:Durchmusterung objects