Elias 2-27

{{Starbox image

| image = 250px

| caption = Protoplanetary disk surrounding the young star Elias 2-27, located some 360 light years away{{cite web|title=Spirals with a Tale to Tell|url=https://www.eso.org/public/images/potw1640a/|website=www.eso.org|access-date=6 October 2016}}

}}

{{Starbox observe

| epoch = J2000.0

| constell = Ophiuchus

| ra = {{RA|16|26|45.032}}

| dec = {{DEC|-24|23|07.79}}

| appmag_v = 13.32

}}

{{Starbox character

| type = Pre-main-sequence star

| class = M0

}}

{{Starbox astrometry

| prop_mo_ra = -7.954

| prop_mo_dec = -28.295

| pm_footnote =

| parallax = 9.0853

| p_error = 0.8505

| parallax_footnote =

}}

{{Starbox detail

| source =

| mass = 0.46{{±|0.02|0.03}}

| radius = 2.3

| luminosity =

| luminosity_bolometric =

| luminosity_visual =

| habitable_inner =

| habitable_outer =

| gravity =

| temperature = 3850

| metal =

| metal_fe =

| rotation =

| rotational_velocity =

| age_myr = 0.8

}}

{{Starbox catalog

| names = {{odlist|2MASS=J16264502-2423077|Gaia DR2=6049161819498750208}}

}}

{{Starbox reference

| Simbad = 2MASS+J16264502-2423077

}}

Elias 2-27 (2MASS J16264502-2423077) is a YSO star with a protoplanetary disk around it, located in the Ophiuchus Molecular Cloud (ρ Oph Cld, 5 Oph Cld, Ophiuchus Dark Cloud), a star-forming region in the Ophiuchus constellation, some {{convert|360|ly|pc|abbr=off|lk=on}} away. This star system became the first ever observed with density waves in the disk, giving it a spiral structure. Elias 2-27 is located near the double star Rho Ophiuchi (5 Ophiuchi).{{cite news |url= http://scitechdaily.com/astronomers-discover-density-waves-in-protoplanetary-disk-surrounding-elias-2-27/ |title= Astronomers Discover Density Waves in Protoplanetary Disk Surrounding Elias 2-27 |author= Max Planck Institute |publisher= SciTechDaily |date= 6 October 2016 }}{{cite web |author= Charles Blue |url= https://public.nrao.edu/news/pressreleases/2016-alma-elias-spiral |title= Image Release: Spiral Arms Embrace Young Star |date= 29 September 2016 |publisher= National Radio Astronomy Observatory }}

Disk

In 2016, it was discovered that disk perturbations from density waves organized the disk debris into a pinwheel structure, with sweeping spiral arms; using observations from the Atacama Large Millimeter Array (ALMA) radio telescope. This marks the first instance of such an observation in a protoplanetary disk, though they have been previously predicted. The spiral arms start at {{convert|100|AU|mi km|abbr=on}} and extend out to {{convert|300|AU|mi km|abbr=on}}.{{cite news |url= https://astronomynow.com/tag/elias-2-27/ |title= Protoplanetary disc's spiral arms embrace young star |date= 1 October 2016 |publisher= Astronomy Now }} The disk has a 14 AU wide gap at 69 AU radius with a reduced amount of dust.{{citation|arxiv=2103.14048|year=2021|title=Spiral Arms and a Massive Dust Disk with Non-Keplerian Kinematics: Possible Evidence for Gravitational Instability in the Disk of Elias 2–27|doi=10.3847/1538-4357/abf243 |last1=Paneque-Carreño |first1=T. |last2=Pérez |first2=L. M. |last3=Benisty |first3=M. |last4=Hall |first4=C. |last5=Veronesi |first5=B. |last6=Lodato |first6=G. |last7=Sierra |first7=A. |last8=Carpenter |first8=J. M. |last9=Andrews |first9=S. M. |last10=Bae |first10=Jaehan |last11=Henning |first11=Th. |last12=Kwon |first12=W. |last13=Linz |first13=H. |last14=Loinard |first14=L. |last15=Pinte |first15=C. |last16=Ricci |first16=L. |last17=Tazzari |first17=M. |last18=Testi |first18=L. |last19=Wilner |first19=D. |journal=The Astrophysical Journal |volume=914 |issue=2 |page=88 |bibcode=2021ApJ...914...88P |s2cid=232380120 |doi-access=free }} The disk is very massive at 0.08{{±|0.04}}{{Solar_mass}}.{{citation|arxiv=2104.09530|year=2021|title=A Dynamical Measurement of the Disk Mass in Elias 2–27|doi=10.3847/2041-8213/abfe6a |last1=Veronesi |first1=Benedetta |last2=Paneque-Carreño |first2=Teresa |last3=Lodato |first3=Giuseppe |last4=Testi |first4=Leonardo |last5=Pérez |first5=Laura M. |last6=Bertin |first6=Giuseppe |last7=Hall |first7=Cassandra |journal=The Astrophysical Journal Letters |volume=914 |issue=2 |pages=L27 |bibcode=2021ApJ...914L..27V |s2cid=233307149 |doi-access=free }}

{{OrbitboxPlanet begin

| name =

| table_ref =

| period_unit = day

}}

{{OrbitboxPlanet disk

| disk = protoplanetary disk

| periapsis = 5

| apoapsis = 300

| inclination = 56.2{{±|0.8}}

}}