What’s in a name?

Esahubble_potw2339a_1024

esahubble_potw2339a September 25th, 2023

Credit: ESA/Hubble & NASA, R. Tully

This Hubble Picture of the Week includes the pithily-named galaxy SDSS J103512.07+461412.2, visible in the centre of this image as a dispersed sweep of dust and stars with a denser, brighter core. SDSS J103512.07+461412.2 is located 23 million light-years from Earth in the constellation Ursa Major. The seemingly rambling name is because this galaxy was observed as part of the Sloan Digital Sky Survey (SDSS), a massive survey that began in 2000 with the aim of observing and cataloguing vast numbers of astronomical objects. So far, it has recorded several hundred million astronomical objects. In the early days of astronomy catalogues, astronomers painstakingly recorded individual objects one by one. As an example, the Messier catalogue includes only 110 objects, identified by the astronomer Charles Messier because they were all getting in the way of his comet-hunting efforts. As the Messier catalogue is so limited, it is sufficient to simply refer to those objects as M1 to M110. In contrast, when a survey as massive in scope as the SDSS is involved, and when huge volumes of data need to be processed in an automated manner, the names assigned to objects need to be both longer, and more informative.  To that end, every SDSS object has a designation that follows the format of: ‘SDSS J’, followed by the right ascension (RA), and then the declination (Dec). RA and Dec define the position of an astronomical object in the night sky. RA is analogous to longitude here on Earth, whilst the Dec corresponds to latitude. To be more exact, RA measures the longitudinal distance of an astronomical object from the point where the celestial equator (the mid-point between the north and south celestial poles) intersects with the ecliptic (the plane in which Earth orbits around the Sun). The entire night sky is then carved into 24 slices, known as ‘hours’, measured eastwards from that starting point (which is designated as zero hour). This means that the RA can be expressed in ‘hours’, ‘minutes’ and ‘seconds’. Dec is the angle north or south of the celestial equator, and is expressed in degrees. The RA and Dec of the objects featured in each Hubble Picture of the Week can be found on the lower right side of the webpage! Thus, the SDSS J103512.07+461412.2 name simply tells us that the galaxy can be found 10 hours, 35 minutes and 12 seconds east of the zero-hour point on the celestial equator, and just over 46 degrees to the north of the celestial equator. So that lengthy name is really an identifier and a detailed location in one! [Image Description: A galaxy in the centre of a wide view of space. It is surrounded by a variety of differently-shaped small galaxies. A wide and very flat spiral galaxy, and one star with four prominent diffraction spikes, are noticeable. The galaxy itself is a broad horizontal streak of tiny stars, extending left and right from a dense and bright core of stars in the centre.]

Provider: Hubble Space Telescope | ESA

Image Source: https://esahubble.org/images/potw2339a/

Curator: ESA/Hubble, Baltimore, MD, United States

Image Use Policy: Creative Commons Attribution 4.0 International License

Image Details

Image Type
Observation
Object Name
SDSS J103512.07+461412.2
Esahubble_potw2339a_128
 

Position Details

Position (ICRS)
RA = 10h 35m 12.4s
DEC = 46° 14’ 14.7”
Orientation
North is 35.2° CW
Field of View
3.2 x 1.6 arcminutes
Constellation
Ursa Major

Color Mapping

  Telescope Spectral Band Wavelength
Blue Hubble (ACS) Optical (V) 606.0 nm
Green Hubble (ACS) Optical (V) 606.0 nm
Green Hubble (ACS) Optical (I) 814.0 nm
Red Hubble (ACS) Optical (I) 814.0 nm
Spectrum_base
Blue
Green
Green
Red
Esahubble_potw2339a_1280
×
ID
potw2339a
Subject Category
Subject Name
SDSS J103512.07+461412.2
Credits
ESA/Hubble & NASA, R. Tully
Release Date
2023-09-25T06:00:00
Lightyears
Redshift
Reference Url
https://esahubble.org/images/potw2339a/
Type
Observation
Image Quality
Distance Notes
Facility
Hubble Space Telescope, Hubble Space Telescope, Hubble Space Telescope, Hubble Space Telescope
Instrument
ACS, ACS, ACS, ACS
Color Assignment
Blue, Green, Green, Red
Band
Optical, Optical, Optical, Optical
Bandpass
V, V, I, I
Central Wavelength
606, 606, 814, 814
Start Time
Integration Time
Dataset ID
None, None, None, None
Notes
Coordinate Frame
ICRS
Equinox
J2000
Reference Value
158.80167028239885, 46.23742858023907
Reference Dimension
3846.0, 1901.0
Reference Pixel
1923.0, 950.5
Scale
-1.3875952105571877e-05, 1.3875952105571877e-05
Rotation
-35.240000000000116
Coordinate System Projection:
TAN
Quality
Full
FITS Header
Notes
Creator (Curator)
ESA/Hubble
URL
https://esahubble.org
Name
Email
Telephone
Address
ESA Office, Space Telescope Science Institute, 3700 San Martin Dr
City
Baltimore
State/Province
MD
Postal Code
21218
Country
United States
Rights
Creative Commons Attribution 4.0 International License
Publisher
ESA/Hubble
Publisher ID
esahubble
Resource ID
potw2339a
Metadata Date
2023-09-13T22:59:07+02:00
Metadata Version
1.1
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Detailed color mapping information coming soon...

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There is no distance meta data in this image.

 

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