Hickson Compact Group 40

Stsci_2022-012a_1024

stsci_2022-012a April 19th, 2022

Credit: NASA, ESA and STScI

NASA is celebrating the Hubble Space Telescope’s 32nd birthday with a stunning look at an unusual close-knit collection of five galaxies, called the Hickson Compact Group 40.

This menagerie includes three spiral-shaped galaxies, an elliptical galaxy, and a lenticular (lens-like) galaxy. Somehow, these different galaxies crossed paths in their evolution to create an exceptionally crowded and eclectic galaxy sampler.

Caught in a leisurely gravitational dance, the whole group is so crowded that it could fit within a region of space that is less than twice the diameter of our Milky Way’s stellar disk.

Though such cozy galaxy groupings can be found in the heart of huge galaxy clusters, these galaxies are notably isolated in their own small patch of the universe, in the direction of the constellation Hydra.

One possibility is that there’s a lot of dark matter (an unknown and invisible form of matter) associated with these galaxies. If they come close together, then the dark matter can form a big cloud within which the galaxies are orbiting. As the galaxies plow through the dark matter they feel a frictional force due to its gravitational effects. This slows their motion and makes the galaxies lose energy so they fall together.

Therefore, this snapshot catches the galaxies at a very special moment in their lifetimes. In about 1 billion years they will eventually collide and merge to form a giant elliptical galaxy.

Astronomers have studied this compact galaxy group not only in visible light, but in radio, infrared, and X-ray wavelengths. Almost all of them have a compact radio source in their cores, which could be evidence for the presence of super-massive black holes. X-ray observations show that the galaxies have been gravitationally interacting due to the presence of a lot of hot gas among the galaxies. Infrared observations reveal clues to the rate of new star formation.

Though over 100 such compact galaxy groups have been cataloged in sky surveys going back several decades, Hickson Compact Group 40 is one of the most densely packed. Observations suggest that such tight groups may have been more abundant in the early universe and provided fuel for powering black holes, known as quasars, whose light from superheated inflating material blazed across space. Studying the details of galaxies in nearby groups like this help astronomers sort out when and where galaxies assembled themselves, and what they are assembled from.

“I remember seeing this on a sky survey and saying, ‘wow look at that!’” said Paul Hickson of the University of British Columbia, Vancouver, Canada. “All that I was using at the time was a big plastic ruler and a magnifying glass while looking over sky survey prints.” He re-discovered the group by browsing through a collection of peculiar galaxies first published by Halton Arp in 1966.

Hubble was deployed into orbit around Earth by the NASA astronauts aboard the space shuttle Discovery, on April 25, 1990. The telescope has taken 1.5 million observations to date, of approximately 50,000 celestial targets. This treasure trove of knowledge about the universe is stored for public access in the Mikulski Archive for Space Telescopes, at the Space Telescope Science Institute in Baltimore, Maryland.

Hubble’s unique capabilities in observing visible and ultraviolet light are a critical scientific complement to the infrared light observations of the new Webb Space Telescope.

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington, D.C.

Provider: Space Telescope Science Institute

Image Source: https://hubblesite.org/contents/news-releases/2022/news-2022-012

Curator: STScI, Baltimore, MD, USA

Image Use Policy: http://hubblesite.org/copyright/

Image Details

Image Type
Observation
Object Name
HCG 40 Arp 321 VV 116
Subject - Local Universe
Galaxy > Type
Galaxy > Component
Galaxy > Grouping > Multiple

Distance

Universescale3
300,000,000 light years
Stsci_2022-012a_128
 

Position Details

Position (FK5)
RA = 9h 38m 58.3s
DEC = -4° 50’ 59.4”
Orientation
North is 41.6° CCW
Field of View
2.7 x 2.5 arcminutes
Constellation
Hydra

Color Mapping

  Telescope Spectral Band Wavelength
Blue Hubble (WFC3/UVIS) Optical (B) 475.0 nm
Green Hubble (WFC3/UVIS) Optical (V) 606.0 nm
Red Hubble (WFC3/UVIS) Optical (Halpha + [NII]) 665.0 nm
Red Hubble (WFC3/UVIS) Optical (I) 814.0 nm
Spectrum_base
Blue
Green
Red
Red
Stsci_2022-012a_1280
×
ID
2022-012a
Subject Category
C.5.1   C.5.4   C.5.5.2  
Subject Name
HCG 40, Arp 321, VV 116
Credits
NASA, ESA and STScI
Release Date
2022-04-19T00:00:00
Lightyears
300,000,000
Redshift
300,000,000
Reference Url
https://hubblesite.org/contents/news-releases/2022/news-2022-012
Type
Observation
Image Quality
Good
Distance Notes
Distance in lightyears
Facility
Hubble, Hubble, Hubble, Hubble
Instrument
WFC3/UVIS, WFC3/UVIS, WFC3/UVIS, WFC3/UVIS
Color Assignment
Blue, Green, Red, Red
Band
Optical, Optical, Optical, Optical
Bandpass
B, V, Halpha + [NII], I
Central Wavelength
475, 606, 665, 814
Start Time
Integration Time
Dataset ID
Notes
Coordinate Frame
FK5
Equinox
2000.0
Reference Value
144.7430137320000085, -4.8498309191100004
Reference Dimension
4021.0000000000000000, 3773.0000000000000000
Reference Pixel
3054.2274169900001652, 1146.7368469200000618
Scale
0.0000110121951274, 0.0000110121951274
Rotation
41.5966255624720702
Coordinate System Projection:
TAN
Quality
Full
FITS Header
Notes
Creator (Curator)
STScI
URL
http://hubblesite.org
Name
Space Telescope Science Institute Office of Public Outreach
Email
outreach@stsci.edu
Telephone
410-338-4444
Address
3700 San Martin Drive
City
Baltimore
State/Province
MD
Postal Code
21218
Country
USA
Rights
http://hubblesite.org/copyright/
Publisher
STScI
Publisher ID
stsci
Resource ID
STSCI-H-p22012a-f-4251x4691.tif
Metadata Date
2022-07-07T08:49:04-04:00
Metadata Version
1.2
×

 

Detailed color mapping information coming soon...

×
Universescalefull
300,000,000 light years