NASA has just realized one of the deepest images of the Universe from James Webb a few days before July 12
Article by: Andacs Robert Eugen, on 07 July 2022, at 01:03 am Los Angeles time
A few days before July 12, 2022, when the James Webb Space
Telescope is about to show us more images of the distant universe, exoplanets, and galaxies (Read more here), NASA is now showing us a deep image of the
universe captured by the telescope in May.
The image you can see above was made using Webb's Fine Guidance Sensor (FGS) from the Canadian space agency.
It took Webb more than 72 exposures and 32 hours of observations to take, according to Webb scientists, "one of the deepest images of the universe ever made."
The image shows stars and galaxies at an impressive distance, and even though it was not an image for scientific observation, this test image shows us the power of the telescope and how long Webb can remain stuck on the same target.
"When FGS' aperture is open, it is not using color filters like the other science instruments - meaning it is impossible to study the age of the galaxies in this image with the rigor needed for scientific analysis. But even when capturing unplanned imagery during a test, FGS is capable of producing stunning views of the cosmos," said NASA.
What you see above is indeed one of the deepest images of the Universe ever made, but let's not confuse it with the image that comes on July 12th. That will probably be much deeper and will not be a test image like this.
"With the Webb telescope achieving better-than-expected image quality, early in commissioning we intentionally defocused the guiders by a small amount to help ensure they met their performance requirements. When this image was taken, I was thrilled to clearly see all the detailed structure in these faint galaxies. Given what we now know is possible with deep broad-band guider images, perhaps such images, taken in parallel with other observations where feasible, could prove scientifically useful in the future," said Neil Rowlands, program scientist for Webb's Fine Guidance Sensor, at Honeywell Aerospace.
"The FGS image is colored using the same reddish color scheme that has been applied to Webb's other engineering images throughout commissioning. In addition, there was no "dithering" during these exposures. Dithering is when the telescope repositions slightly between each exposure. In addition, the centers of bright stars appear black because they saturate Webb's detectors, and the pointing of the telescope didn't change over the exposures to capture the center from different pixels within the camera's detectors. The overlapping frames of the different exposures can also be seen at the image's edges and corners," the space agency continued.
"In this engineering test, the purpose was to lock onto one star and to test how well Webb could control its "roll" - literally, Webb's ability to roll to one side like an aircraft in flight. That test was performed successfully - in addition to producing an image that sparks the imagination of scientists who will be analyzing Webb's science data," said Jane Rigby, Webb's operations scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland.
"The faintest blobs in this image are exactly the types of faint galaxies that Webb will study in its first year of science operations," Rigby said.