A space telescope James Webb has started his day job.
The new photo, taken only for research, was released less than a week after the first photos. On Tuesday, July 12, the US space administration Nasa presented to the general public what Webb is capable of.
In the first year, Webb will photograph space for at least 286 different groups of astronomers. The objects are diverse.
July The picture published on the 19th looks strange to the human eye. It is from the area of infrared, or heat radiation. The picture shows the thermal radiation of the galaxy’s dust.
The image was taken from the center of the spiral galaxy NGC 628. In a normal picture, the galaxy would look like a normal spiral galaxy, like our home galaxy the Milky Way.
The image offers clues about dust movements in galaxies in general.
The image is a combination of different wavelengths. They are combined from three datasets. The image data was collected by the team responsible for the mid-infrared wavelengths of Webb’s images.
I picture compiled with permission from NASA from various files by an astronomer Gabriel Brammer from the University of Copenhagen, Denmark. He is not directly involved in the group filming with Webb.
Brammer defined infrared wavelengths as red, green and blue. Then he combined them into a picture.
The galaxy NGC 628 has previously been imaged with ordinary telescopes. Webb’s predecessor, the Hubble Space Telescope, has also imaged it.
When the image is perpendicularly above the plane of the galaxy, it looks like our Milky Way in the photo.
Infrared light resolution reveals galaxy structures from a new angle.
If our eyes could see at these infrared wavelengths, the night sky might show more from red or purple, says Brammer, according to New Scientist magazine.
The purple color is due to the chemistry of the dust clouds in the galaxy NGC 628. Dust consists of large molecules. They are called polycyclic aromatic hydrocarbons, says Michael Merrifield from the University of Nottingham, UK, according to New Scientist.
Molecules only emit certain wavelengths of light. When Brammer mapped the three wavelengths into red, green and blue, there was very little green involved.
There was more red and blue left. Because of that, the color of the picture is focused on purple.
I picture the data can tell how dust is distributed in galaxies. However, the image is perhaps too detailed for that.
It may not be possible to infer how dust moves in other galaxies.
The picture was amazingly easy to complete, says Brammer. Easy access to data is one of Webb’s advantages.
In principle, any astronomer can compile images from Webb’s data, he says.
A micrometeoroid hit the space telescope sometime between the 22nd and 24th May. It damaged one of Webb’s 18 hexagonal gold-plated mirrors. One large main mirror was assembled from them.
The US space agency NASA has investigated the damage caused by the impact of a small micrometeoroid to the lower part of the mirror.
The extent of the damage can be seen in Webb’s self-portrait. The mirror was damaged worse than initially thought, he says website Space.com. The attached picture shows the status of the mirror in the summary.
The impact does not yet affect the quality of the images. But if a lot of similar ones accumulate over the years, it starts to show in the quality of the pictures.
Nasa prepared for these attacks in the risk calculation in advance. It was known that there are many small stones moving in space. What makes them dangerous is that the speed of the stones can be fierce. The stone then hits the mirror like a bullet.
Now space engineers are considering whether to place the mirror in the opposite direction when Webb is not observing.
If the mirrors would be placed away from Webb’s direction of travel, at least violent head-on collisions with rocks would be avoided.
Webb orbits a small circle about 1.5 million kilometers from Earth at the so-called Lagrange point L2. One round takes half a year.
Webb’s propellant can last even more than 20 years.
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