NGC 4490

{{Short description|Interacting galaxy in constellation Canes Venatici}}

{{Infobox galaxy

| name = NGC 4490

| image = NGC4490.jpg

| caption = NGC 4490 and satellite galaxy, NGC 4485

| epoch = J2000

| type = SB(s)d pec {{cite web

| website=NASA/IPAC Extragalactic Database

| title=Results for object NGC 4490

| url=http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+4490

| access-date=2016-01-18 }}

| ra = {{RA|12|30|36.2390}}

| dec = {{DEC|41|38|38.032}}

| dist_ly = 25.1 ± 5.0 Mly (7.7 ± 1.5 Mpc)

| z = 0.001885{{r|ned}}

| h_radial_v = 565 ± 3 km/s

| appmag_v = 9.8

| size_v = {{Val|6.3|×|3.1|u=arcminute}}

| size = ~{{convert|12.34|kpc|ly|abbr=on|lk=on|order=flip}} (estimated){{r|ned}}

| constellation name = Canes Venatici

| notes =

| names = {{odlist | name= HOLM 414A | IRAS= 12281+4155 | MCG= +07-26-014 | CGCG= 216-008 | VV= 030a | Arp= 269 NED02 | UGC= 7651 | PGC= 41333}}

}}

NGC 4490, also known as the Cocoon Galaxy, is a barred spiral galaxy in the constellation Canes Venatici. It was discovered by German-British astronomer William Herschel on 14 January 1788.{{cite web | url = https://cseligman.com/text/atlas/ngc44a.htm#4490 | title = New General Catalogue Objects: NGC{{nbsp}}4490 | last = Seligman | first = Courtney | website = Celestial Atlas | access-date = 20 April 2025 }} It is known to be of the closest interacting/merging galactic system. The galaxy lies at a distance of 25 million light years from Earth making it located in the local universe. It interacts with its smaller companion NGC 4485 and as a result is a starburst galaxy. NGC 4490 and NGC 4485 are collectively known in the Atlas of Peculiar Galaxies as Arp 269. The two galaxies have already made their closest approach and are rushing away from each other. It has been discovered that NGC 4490 has a double nucleus.{{Cite journal |last1=Lawrence |first1=A. L. |last2=Kerton |first2=C. R. |last3=Struck |first3=Curtis |last4=Smith |first4=Beverly J. |date=2020-02-27 |title=Revealing the Double Nucleus of NGC 4490 |journal=The Astrophysical Journal |volume=891 |issue=1 |pages=11 |doi=10.3847/1538-4357/ab6c6a |arxiv=2001.05601 |bibcode=2020ApJ...891...11L |issn=1538-4357 |doi-access=free }}

NGC 4490 is located 3/4° northwest of beta Canum Venaticorum and with apparent visual magnitude 9.8, can be observed with 15x100 binoculars.{{cite book|last1=Craig Crossen, Gerald Rhemann|title=Sky Vistas: Astronomy for Binoculars and Richest-Field Telescopes|date=2012|publisher=Springer Science+Business Media |isbn=978-3-7091-0626-6|page=233 |url=https://books.google.com/books?id=3vELBwAAQBAJ&pg=PA233}} It is a member of the Herschel 400 Catalogue. It belongs to the Canes II Group. NGC 4490 has a system of satellite galaxies oriented roughly in a plane.{{cite journal | doi=10.1051/0004-6361/202449954 | arxiv=2405.06016 | bibcode=2024A&A...688A.153P | title=The satellite galaxy plane of NGC 4490 in light of ΛCDM | date=2024 | last1=Pawlowski | first1=Marcel S. | last2=Müller | first2=Oliver | last3=Taibi | first3=Salvatore | last4=Júlio | first4=Mariana P. | last5=Kanehisa | first5=Kosuke Jamie | last6=Heesters | first6=Nick | journal=Astronomy & Astrophysics | volume=688 | pages=A153 }}

Stellar stream

A stellar stream 25,000 light years long connects the two interacting galaxies. The stellar stream is made of bright knots and large gas rich pockets. Young blue hot massive stars are formed in this region.{{Cite web |last=information@eso.org |title=Distant view of a galactic crash — NGC 4490 and NGC 4485 (ground-based image) |url=https://www.spacetelescope.org/images/heic1910b/ |access-date=2023-11-25 |website=www.spacetelescope.org |language=en}}

Supernovae and Luminous Red Nova

Two supernovae and one luminous red nova (LRN) have been observed in NGC 4490:

SN 1982F (type unknown, mag. 16) was discovered by Paul Wild on 15 April 1982.{{cite journal | bibcode=1982IAUC.3689....1W| title=Probable Supernova in NGC 4490| last1=Wild| first1=P.| journal=International Astronomical Union Circular| date=1982| issue=3689| page=1}}{{cite web | website=Transient Name Server | title=SN{{nbsp}}1982F | url=https://www.wis-tns.org/object/1982F | publisher = IAU | access-date=5 December 2024}}
AT 2011kp (type LRN, mag. 16.7) was discovered by Giancarlo Cortini and Stefano Antonellini on 16 August 2011.{{cite journal | bibcode=2011CBET.2789....1C | title=PSN J12304185+4137498 in NGC 4490 | last1=Cortini | first1=G. | last2=Borkovits | first2=T. | last3=Szakats | first3=R. | last4=Brimacombe | first4=J. | journal=Central Bureau Electronic Telegrams | date=2011 | issue=2789 | page=1 | url= http://www.cbat.eps.harvard.edu/iau/cbet/002700/CBET002789.txt}}{{cite web | website=Transient Name Server | title=AT{{nbsp}}2011kp | url=https://www.wis-tns.org/object/2011kp | publisher = IAU | access-date=20 April 2025}}
SN 2008ax (type II, mag. 13) was discovered by the Lick Observatory Supernova Search (LOSS) on 3 March 2008{{cite journal | bibcode=2008CBET.1280....1M| title=Possible Supernova in NGC 4490| last1=Mostardi| first1=R.| last2=Li| first2=W.| last3=Filippenko| first3=A. V.| journal=Central Bureau Electronic Telegrams| date=2008| issue=1280| page=1}} and by Kōichi Itagaki on 4 March 2008.{{cite journal | bibcode=2008CBET.1286....1N| title=Supernova 2008ax in NGC 4490| last1=Nakano| first1=S.| journal=Central Bureau Electronic Telegrams| date=2008| issue=1286| page=1}}{{cite web

|title = Supernova 2008ax in NGC 4490

|website = Rochester Astronomy

|author = David Bishop

|url = https://www.rochesterastronomy.org/sn2008/sn2008ax.html

|access-date = 5 December 2024

}}{{cite web | website=Transient Name Server | title=SN{{nbsp}}2008ax | url=https://www.wis-tns.org/object/2008ax | publisher = IAU | access-date=5 December 2024}}

Gallery

Result of a galactic crash.jpg|Extreme tidal forces have carved out the shapes and properties of NGC 4490.{{cite web|title=Bursting with Starbirth|url=https://www.spacetelescope.org/news/heic1716/|website=www.spacetelescope.org|access-date=28 September 2017}}