UDFy-38135539
| UDFy-38135539 | |
|---|---|
Hubble Space Telescope image of UDFy-38135539.
|
|
| Observation data | |
| Constellation | Fornax |
| Right ascension | 03h 32m 38.13s |
| Declination | −27° 45′ 53.9″ |
| Distance | 13.1 billion light-years (light travel distance) ~30 billion light-years (present proper distance) |
| Apparent magnitude (V) | V fainter than 30.2 H160 = 28.1 (detected by HST in J and H bands) |
| Characteristics | |
| Type | Dwarf |
| Number of stars | 1 billion (1×109) |
| Size | 10,000 ly (diameter) |
| Apparent size (V) | 0.0025 x 0.0025 |
| Other designations | |
| HUDF.YD3, TST2010 3, MDC2010 1721 | |
Coordinates: 
3h 32m 38.13s, −27° 45′ 53.9″
UDFy-38135539 (also known as "HUDF.YD3") is the Hubble Ultra Deep Field (UDF) identifier for a galaxy which was calculated as of October 2010[update] to have a light travel time of 13.1 billion years with a present proper distance of around 30 billion light-years.
It was discovered by three teams in September 2009 in sensitive infrared Hubble Space Telescope images and identified by these as source UDF-38135539 (R Bouwens et al.,) source HUDF.YD3 (A Bunker et al.) and source 1721 (R McLure et al.), and additionally reported in the Astrophysical Journal, and the Monthly Notices of the Royal Astronomical Society. All teams independently identified the source likely an extremely distant galaxy because there were no measurable light at visible wavelengths (caused by absorption of hydrogen gas along the line of sight). Following the discovery of this candidate distant galaxy, another team targeted this object with ground-based spectroscopy to confirm the distance, reporting a redshift z=8.6. However, attempts to replicate this observation strongly suggest the original claim was in error, meaning that at the present time the galaxy only has a photometric redshift estimate.
...
Wikipedia