After NASA announced that the James Webb Space Telescope nears completion of its first phase of aligning its primary mirror, it released 18 images of a single star. These photos were taken by Webb’s 18 primary mirror segments. It then resulted in an image mosaic of 18 randomly organized dots of starlight.
James Webb Telescope Images
The same star that the observatory viewed was rendered deliberately into a hexagonal shape 18 times. The shots were initially unfocused but eventually were aligned perfectly into a sharp focus. What came out was a star repeated in a hexagonal pattern which is a stunning reminiscence of a celestial snowflake.
According to one of NASA’s tweets, this confirms that each of Webb’s mirror segments can see starlight. Thus, declaring the mission as a success. With this, the team has now started the “Segment Alignment” phase. This will fix significant positioning errors in the individual segments of Webb’s primary mirror. They will also include the update of the secondary mirror’s alignment.
Matthew Lallo, systems scientist and Telescopes Branch manager at the Space Telescope Science Institute, also said that the familiar arrangement would provide the wavefront team with an intuitive and more natural way of visualizing the changes. He confirms that they can now view the primary mirror slowly forming into its exact shape.
When the second alignment is completed, the team will then move on to the next phase. This is what they call “image stacking”. This will bring all 18 images on top of each other to form one clear view. What seems like a simple and blurry photo of a starlight will now become the foundation to align and focus the telescope. This will allow it to send unprecedented views of the universe a few months from now.
The NASA Webb team is ecstatic with this new development. The scientists were delighted to see that light is now making its way into NIRCam (Near Infrared Camera). This was the first phase and took months to align the observatory’s primary mirror using this instrument.
How It All Started
The James Webb telescope image capturing process began on February 2, 2022. The team repointed Webb towards 156 different positions around the approximated location of the star. This endeavor generated up to 1,560 images through the NIRCam’s ten powerful detectors totaling 54 gigabytes of raw data.
This process took 25 hours to be finished. But within the first six hours and 16 exposures, it has located the target star in each of the 18 mirror segments. They then stitched the images to come up with a single mosaic that captured the signature of each mirror all in a single frame: an image with more than 2 billion pixels.
Michael McElwain, Webb observatory project scientist at NASA’s Goddard Space Flight Center, said that while the launch of the Webb was an exciting event in itself, this was something more exhilarating for them. He calls this their pinnacle moment, the time when light from a star successfully makes its way “through the system down onto a detector.”
From here on, the James Webb telescope images will only be more precise and more detailed. This is due to its three other instruments that have arrived at their intended cryogenic operating temperatures and their start of data gathering.
The team is now expecting the observatory’s first scientific images this year in the summer. What’s even more crucial for them is that this development confirms that the Webb telescope is fully functioning. They are now busy preparing the telescope for its entire scientific operations using four of its instruments in the months ahead.
