Pi Draconis

{{Starbox begin

| name = Pi Draconis

}}

{{Starbox observe

| epoch = J2000.0

| equinox = J2000.0 (ICRS)

| constell = Draco

| ra = {{RA|19|20|40.09333}}

| dec = {{DEC|+65|42|52.3095}}

| appmag_v = 4.59

}}

{{Starbox character

| class = A2 IIIs

| b-v = +0.02

| u-b = +0.06

| r-i =

| variable =

}}

{{Starbox astrometry

| radial_v = {{Val|−28.1|1.1}}

| prop_mo_ra = +15.09

| prop_mo_dec = +41.12

| parallax = 14.25

| p_error = 0.12

| parallax_footnote =

| absmag_v = +0.37

}}

{{Starbox detail

| source =

| mass = 2.70

| radius = 3.2

| luminosity = 60

| temperature = 9,125

| gravity = 3.80

| metal_fe = 0.42

| rotational_velocity = {{Val|26|1}}

| age_myr = 350

}}

{{Starbox catalog

| names = {{odlist|B=π Dra | F=58 Dra | BD=+65°1345 | FK5=3547 | HD=182564 | HIP=95081 | HR=7371 | SAO=18299 }}

}}

{{Starbox reference

| Simbad = pi.+Dra

}}

Pi Draconis, Latinized from π Draconis, is a solitary star in the northern circumpolar constellation of Draco. It is visible to the naked eye with an apparent visual magnitude of 4.59. Based upon an annual parallax shift of 14.25 mas as measured from Earth, it is located around 229 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of {{Val|0.063|0.10}} due to interstellar dust.

With an age of 350 million years, this is an A-type star of stellar classification A2 IIIs, where the luminosity class of III typically indicates an evolved giant star and the 's' means the spectrum displays sharp absorption lines. It is a candidate Am star, meaning there are some chemical peculiarities. The measured angular size is {{Val|0.427|0.062|u=arc seconds}}. At the estimated distance of Pi Draconis, this yields a physical size of about 3.2 times the radius of the Sun. It has about 2.70 times the mass of the Sun and is radiating 60 times the solar luminosity from its photosphere at an effective temperature of 9,125 K.

References

{{reflist|refs=

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{{citation

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| arxiv=0901.1206 | postscript=.

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{{citation

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}} The radius (R_*) is given by:

: $\begin{align} 2\cdot R_*
& = \frac{(70.2\cdot 0.427\cdot 10^{-3})\ \text{AU}}{0.0046491\ \text{AU}/R_{\bigodot}} \\
& \approx 6.4\cdot R_{\bigodot}
\end{align}$

{{citation | postscript=.

| title=Elemental Abundance Analyses with DAO Spectrograms. XXXIV. A Three-Dimensional Graphical Examination of the Elemental Abundances of the Mercury-Manganese and Metallic-Line Stars

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| journal=Publications of the Astronomical Society of the Pacific

| volume=126 | issue=938 | pages=345 | date=April 2014

| doi=10.1086/676335 | bibcode=2014PASP..126..345Y | doi-access=free }}

{{citation

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