The largest near-infrared image of galaxies ever made by the Hubble Space Telescope has provided a playing field for astronomers looking for potential targets for the James Webb Space Telescope.
The image is the result of a project called 3D-DASH and was captured by the Hubble Space TelescopeWide Field Camera 3 (WFC3), with additional archive data from Hubble’s Advanced Survey Camera. It occupies 1.35 square degrees of the sky, equivalent to about six full moons, and contains thousands of galaxies. The goal is to identify galaxies worthy of further study by the James Webb Space Telescope and another telescopes in the future.
“I’m curious about the giant galaxieswhich are the most massive in the universe formed by the merger of other galaxies, “said Lamiya Mowla, an astronomer at the Dunlap Institute for Astronomy and Astrophysics at the University of Toronto and a leader in new research. statement. “How did their structures grow and what drove the changes in their shape? It was difficult to study these extremely rare events using existing images, which is what motivated the design of this large survey.”
Related: The best images from the Hubble Space Telescope of all time!
It would have taken Hubble about 2,000 hours of observation to create such a large image, but Mowla’s team used a new technique called Drift and Shift (DASH), which takes several photographs and joins them together, bringing together eight individual images. times larger. than the typical WFC3 field of view (0.04 x 0.04 degrees). Also, instead of taking a picture every time it orbits EarthHubble could take eight images using the DASH technique. With a total of 1,256 individual WFC3 shots, it only took 250 hours of observation to complete the entire mosaic.
Most galaxies in the image are visible as infrared light spots. The farthest ones look like they existed about 10 billion years ago, and the light from the bright regions of star formation within them has been shifted to red by expansion of the universe in near-infrared wavelengths. You can see these galaxies in more detail in an interactive online version of the galaxy image 3D-Dash Image Explorer.
Unlike Hubble, Webb will be able to scrutinize these galaxies in more detail, thanks to the increased light-picking power of the new telescope’s 6.5-meter (21.3-foot) mirror image. With the first scientific quality images from Webb will be released on July 12ththe publication of 3D-DASH data is timely.
A selection of the full 3D-DASH image, which is the largest mosaic ever assembled by the Hubble Infrared Space Telescope. (Image credit: Lamiya Mowla)
For larger survey images, astronomers will have to wait for those from the European Space Agency Euclid mission and NASA Nancy Grace Roman Space Telescopewhich will have larger fields of view (0.79 x 1.16 degrees and 0.8 x 0.4 degrees, respectively) than Hubble and Webb and will be launched in 2023 and 2027, respectively.
The research has been accepted for publication in The Astrophysical Journal and a pre-printed version is available via arXiv database.
Follow Keith Cooper on Twitter @ 21stCenturySETI. follow us on Twitter @Spacedotcom yen Facebook.