View source for Astronomy:YZ Reticuli

{{Short description|2020 Nova in the constellation Reticulum}}
{{Starbox begin}}
{{Starbox image
 | image=
{{Location mark
|image=Reticulum_IAU.svg|alt=|float=center|width=280
|label=|position=right
|mark=Red circle.svg|mark_width=12|mark_link=Nova 2020|x=508|y=301
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|caption=Location of YZ Reticuli (circled)
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{{Starbox observe 
| epoch = J2000.0
| constell = Reticulum
| ra = {{RA|03|58|29.55}}<ref name=dr2/>
| dec = {{DEC|-54|46|41.2}}<ref name=dr2/>
| appmag_v = 3.7 - 18.0<ref name=vsx>{{cite journal|bibcode=2006SASS...25...47W|title=The International Variable Star Index (VSX)|journal=The Society for Astronomical Sciences 25th Annual Symposium on Telescope Science. Held May 23–25|volume=25|pages=47|last1=Watson|first1=C. L.|year=2006}}</ref>
}} 
{{Starbox character 
| class =
| variable=[[Astronomy:Nova|Nova]]<ref name=atel13867/> {{nowrap|(sdB?/DA?)<ref name=kilkenny/>}}
}} 
{{Starbox astrometry
| radial_v = 
| prop_mo_ra = 7.244<ref name=dr2/>
| prop_mo_dec = 2.984<ref name=dr2/>
| parallax = 0.3161
| p_error = 0.0464
| parallax_footnote =<ref name=dr2>{{cite DR2|4731746232846281344}}</ref>
| dist_pc = {{val|2703|365|293}}<ref name="BailerJones"/>
}} 
{{Starbox catalog
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{{Starbox reference
| Simbad = YZ+Ret
}}
{{Starbox end}}

'''YZ Reticuli''', also known as '''Nova Reticuli 2020''' was a [[Astronomy:Naked eye|naked eye]] [[Astronomy:Nova|nova]] in the constellation [[Astronomy:Reticulum|Reticulum]] discovered on July 15, 2020. Previously it was known as a [[Astronomy:Super soft X-ray source#VY Scl cataclysmic variables|VY Sculptoris type]] object with the designation '''MGAB-V207'''.

==VY Sculptoris type==
The variability of the object was first discovered by an amateur astronomer, Gabriel Murawski, and reported on August 6, 2019 with the name MGAB-V207.<ref>{{Cite web|url=https://aavso.org/vsx/index.php?view=detail.top&oid=844392|title=VSX : Detail for N Ret 2020|website=International Variable Star Index}}</ref> Archive photometry data from the [[Astronomy:Catalina Real-time Transient Survey|Catalina Real-time Transient Survey]] and [[Astronomy:All Sky Automated Survey for SuperNovae|ASAS-SN]] showed nova-like (NL) brightness variations between [[Astronomy:Magnitude|magnitudes]] 15.8 and 17.0, exhibiting a deep dimming event in late 2006.<ref>{{Cite web|website=Polskiego Towarzystwa Miłośników Astronomii|url=http://ptma.pl/tar/TAR_2019_MGAB_VY_Scl.pdf|title=The discovery of eleven nova-like VY Scl type stars|last1=Murawski|first1=G.|year=2019}}</ref> The spectrum shows a [[Astronomy:Subdwarf B star|hot subdwarf (sdB)]] or a [[Astronomy:White dwarf|white dwarf]] origin,<ref name=kilkenny>{{cite journal|bibcode=2015MNRAS.453.1879K|title=The Edinburgh-Cape Blue Object Survey - IV. Zone 3: Galactic latitudes -40° > b > -50°|journal=[[Organization:Monthly Notices of the Royal Astronomical Society|Monthly Notices of the Royal Astronomical Society]]|volume=1|display-authors=0|last1=Kilkenny|first1=D.|year=2015|issue=2|page=1879|doi=10.1093/mnras/stv1771|doi-access=free}}</ref> which is consistent with VY Scl type objects.

==Nova eruption==
[[File:YZRetLightCurve.png|thumb|left|The light curve of YZ Reticuli plotted from AAVSO data]]
On July 15, 2020 [[Biography:Robert H. McNaught|Robert H. McNaught]] discovered a bright [[Astronomy:Transient astronomical event|transient]] ([[Astronomy:Magnitude|magnitude]] 5.3)<ref>{{cite web |title=CBET 4811: 20200715 : APPARENT NOVA IN RETICULUM (LIMITED ACCESS)|url=http://www.cbat.eps.harvard.edu/iau/cbet/004800/CBET004811.txt |website=[[Organization:Central Bureau for Astronomical Telegrams|Central Bureau for Astronomical Telegrams]] |publisher=IAU |access-date=15 July 2020}}</ref> coincident with the position of MGAB-V207 and it was [[Physics:Astronomical spectroscopy|spectroscopically]] confirmed by the [[Astronomy:Southern African Large Telescope|Southern African Large Telescope]] (SALT) as a classical [[Astronomy:Nova|nova]] on July 16. The spectrum includes [[Physics:Balmer series|Balmer]], O{{smallcaps|I}} and [[Chemistry:Ferrous|Fe<small>II</small>]] emission lines with P Cygni profiles.<ref name=atel13867/> Spectrum analysis from observations by the [[Astronomy:Siding Spring 2.3 m Telescope|Advanced Technology Telescope]] revealed a similarity to Nova Sagittarii 1991, three days after maximum brightness.<ref>{{cite journal|bibcode=2020ATel13874....1C|display-authors=0|author1=Carr, A. |author2=Said, K. |author3=Davis, T. M.|url=http://www.astronomerstelegram.org/?read=13874|title=WiFeS follow-up observations of the naked-eye nova associated to MGAB-V207|journal=[[Astronomy:The Astronomer's Telegram|The Astronomer's Telegram]]|date=2020-07-18|volume=13874 |page=1 }}</ref> Pre-discovery images showed that the brightness peak happened on July 9, 2020 at magnitude 3.7.<ref>{{cite web |title=CBET 4812: 20200716 : NOVA RETICULI 2020 (LIMITED ACCESS)|url=http://www.cbat.eps.harvard.edu/iau/cbet/004800/CBET004812.txt |website=Central Bureau for Astronomical Telegrams |publisher=IAU |access-date=16 July 2020}}</ref> In the days after the discovery, the nova faded by 0.2-0.3 magnitudes per day.<ref>{{Cite web|url=https://www.aavso.org/apps/webobs/results/?star=NOVA%20RETICULI%202020&num_results=200|title=Recent Nova Reticuli 2020 observations in AAVSO|website=AAVSO}}</ref> This is the third case when an already known cataclysmic variable has undergone a classical nova eruption, following V407 Cygni and [[Astronomy:V392 Persei|V392 Persei]].<ref>{{cite journal|bibcode= 2020ATel13868....1L|display-authors=0|author1=Li, K. |author2=Kong, A. |author3=Aydi, E.|url=http://www.astronomerstelegram.org/?read=13868|title=Fermi-LAT detection of the naked-eye classical nova MGAB-V207|journal=[[Astronomy:The Astronomer's Telegram|The Astronomer's Telegram]]|date=2020-07-16|volume=13868 |page=1 }}</ref>

The orbital period of YZ Reticuli is 0.1324539 days (3 hours, 10 minutes, and 44 seconds), but in the months following the eruption, the lightcurve also oscillated with periods of 0.1384 and 0.1339 days. These are likely related to the accretion disk and represent a similar phenomenon to [[Astronomy:Superhump|superhump]]s.<ref name=Schaefer>{{cite journal |doi=10.3847/2515-5172/ac0d5b|arxiv=2106.13907|bibcode=2021RNAAS...5..150S|title=Discovery of 13 New Orbital Periods for Classical Novae|year=2021|last1=Schaefer|first1=Bradley E.|journal=Research Notes of the AAS|volume=5|issue=6|page=150|s2cid=235632263 |doi-access=free }}</ref>

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==See also==
* List of novae in the Milky Way galaxy

==References==
{{reflist|refs=

<ref name=atel13867>{{cite journal|bibcode=2020ATel13867....1A|display-authors=0|author1=Aydi, E. |author2=Buckley, D. A. H. |author3=Chomiuk, L.|url=http://www.astronomerstelegram.org/?read=13867|title=SALT spectroscopic classification of MGAB-V207 as a classical nova|journal=[[Astronomy:The Astronomer's Telegram|The Astronomer's Telegram]]|date=2020-07-16|volume=13867|page=1}}</ref>
<ref name=BailerJones>{{cite journal|bibcode=2018AJ....156...58B|display-authors=0|author1=Bailer-Jones, C. A. L. |s2cid=119289017|title=Estimating Distance from Parallaxes. IV. Distances to 1.33 Billion Stars in Gaia Data Release 2|journal=[[Astronomy:The Astronomical Journal|The Astronomical Journal]]|year=2018|volume=156|issue=2|page=58|doi=10.3847/1538-3881/aacb21|arxiv=1804.10121 |doi-access=free }}</ref>
}}

==External links==
*[https://astropolis.pl/topic/72937-mgab-v207-nowa-klasyczna-widoczna-go%C5%82ym-okiem/ VY Sculptoris type discovery details], July 15, 2020
*[https://astronomy.com/news/observing/2020/07/nova-reticuli-2020-bursts-into-the-southern-skies Nova Reticuli 2020 bursts into the southern skies - Astronomy.com], July 17, 2020
*[https://remanzacco.blogspot.com/2020/07/bright-nova-reticuli-2020.html Bright Nova Reticuli 2020 - blog by Ernesto Guido], July 17, 2020

{{Stars of Reticulum}}

{{DEFAULTSORT:YZ Reticuli}}

[[Category:Novae]]
[[Category:2MASS objects|J03582954-5446411]]
[[Category:Objects with variable star designations|Reticuli, YZ]]

{{Sourceattribution|YZ Reticuli}}