- Jonathan Amos
- BBC science correspondent
This picture doesn’t seem to have much to see. It’s just a cluster of bright red dots with the strange name JADES-GS-z13-0.
But this faint spot image, taken by the James Webb Space Telescope, is the “most distant galaxy” ever confirmed by internationally standardized measurement methods.
This constellation image occurred 325 million years following the Big Bang.
If the universe is 13.8 billion years old, that means we’re looking at JADES-GS-z13-0. When this universe was only 2% of its present age.
The light from this constellation took a long time to reach us.
“I am so proud and grateful to be a part of this moment,” said Dr Emma Curtis-Lake, who was part of an international team that published details of the findings on Friday. Dec.)
Previously, the Hubble Space Telescope which was used before the James Webb Space Telescope. It has discovered the “most distant galaxy” called GN-z11. This galaxy is a little closer to us. Occurs while the universe is regarding 400 million years old only.
But the important thing is The stick has now been passed from Hubble to James Webb. From a great telescope to the next great telescope As scientists try to trace the earliest times when stars were formed,
In fact, NASA’s recent deployment of the James Webb Space Telescope US space agency It has the main objective of finding the first stars to shine in this universe.
JADES-GS-z13-0 Not from that time But we are getting closer every moment. But there was a question. No more distant galaxies have been reported. JADES-GS-z13-0 From observations by the James Webb Space Telescope last summer?
The answer is “maybe” and this uncertainty depends on the differences in the techniques used to determine the distance.
Astronomers use the word “redshift” in terms of distance
It uses a method to measure wavelengths that stretch light as it travels from distant galaxies.
The distance will be farther If there is a lot of stretch This makes the redshift number even higher (the JADES Galaxy has a redshift number of 13.2, which is what the name implies).
Scientists have studied many aspects. to help make this assessment more accurate as well It includes the brightness and color of the studied subject using a few specific filters in the camera. This technique is known as metering.
Different galactic bands, or “slits,” may lighten or darken them in different filters, and can be an indication of their distance.
This is just a guideline. But it’s not always possible to believe.
If there is a lot of dust in a galaxy It may make the subject appear redder. and farther than it is
To measure the most accurate Astronomers tend to use more spectral analysis tools. which is a more detailed technique The components of the light signal are separated into different wavelengths.
This allows them to better locate “rifts” within the galaxy’s spectrum. You can also see the emission lines of elements such as hydrogen, oxygen and neon.
Comparison of measured wavelengths with wavelengths obtained in laboratory experiments. will help to indicate directly that how much light is stretched The same goes for redshift and distance.
Both JADES-GS-z13-0 and GN-z11 were confirmed with a spectrum analyzer. which is an international standard method The higher red shifts seen in reports over the past few months have been attributed to light metering.
This is a tough job all around. The target is very vague. even on a James Webb camera and its 6.5 meter wide giant mirror
Dr. Curtis-Lake And her JADES (JWST Advanced Deep Extragalactic Survey) colleague spent hours collecting fragments of images at the Hub Space Telescope. The original Ble can see
“It’s an incredible piece of sky. It is equivalent to seeing the Queen’s eyes on a pound coin held from arm’s length,” said Dr Rensk Smit of Liverpool John Moores University. that Webb sees tens of thousands of galaxies.”
image source, NASA, ESA, CSA, M. Zamani, JADES COLLABORATION
JADES has made observations that the Hubble Space Telescope has done before. but have studied more deeply
this new space telescope A near-infrared light spectrum detector is installed. The European Space Agency’s powerful near-infrared spectrometer (NIRSpec) is also included. NIRSpec’s job is to thoroughly analyze faint light signals.
It will serve to select objects to study. In that piece of sky The team selected 250 promising objects, four of which turned out to be very distant galaxies.
by the farthest JADES-GS-z13-0 The approaching part is JADES-GS-z12-0, JADES-GS-z11-0 and JADES-GS-z10-0
image source, AIRBUS
NIRSpec is a significant European contribution to the James Webb project.
“The James Webb Space Telescope was built to do this work. and the NIRSpec instrument built by the European Space Agency. It’s at the heart of it,” said Professor Mark McCorn, senior scientific adviser to the European Space Agency.
“Finding the ‘first light’ in the universe requires a cool, big space telescope. and has a light-sensitive infrared camera to find out what might be in the faint galaxies that formed 200-300 million years following the Big Bang.”
“But there are many haystacks. While there are so few needles out there, you need to consider a number of options. Take the little light obtained from each option and convert it into a spectrum. and use a tracer to see if Are they the correct distance and age? Being able to efficiently monitor hundreds of targets at the same time, NIRSpec enables cosmic magnetism to be applied to those haystacks,” he told BBC News.
