NASA’s Webb Opens New Window on Supernova Science - NASA Science
The James Webb Space Telescope (JWST) continues to allow scientists to witness events almost at the beginning of time - at least when the Universe was just 1.8 billion years old. This comes in the form of supernovae or exploding stars, the light from which has just reached the JWST's detectors, having taken some 12 billion years to get there.
How long does it take light to travel 2 meters? To determine how long it takes light to travel 2 meters, you can use the speed of light in a vacuum, which is approximately \( 299,792,458 \) meters per second. The formula to calculate the time it takes for light to travel a certain distance is: \[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \] Plugging in the values: \[ \text{Time} = \frac{2 \, \text{meters}}{299,792,458 \, \text{meters/second}} \] Let's calculate this: \[ \text{Time} \approx 6.67 \times 10^{-9} \, \text{seconds} \] So, it takes approximately 6.67 nanoseconds for light to travel 2 meters.I have previously explained how witnessing an event, the information about which has taken billions of years to arrive is no less witnessing that event than witnessing an event in the same room, information about which took a few nanoseconds to reach us.
And what the cosmologists have seen is far more supernovae than was previously thought.
The recent press release from NASA explains how these events were seen:
‘A Supernova Discovery Machine’
To make these discoveries, the team analyzed imaging data obtained as part of the JWST Advanced Deep Extragalactic Survey (JADES) program. Webb is ideal for finding extremely distant supernovae because their light is stretched into longer wavelengths — a phenomenon known as cosmological redshift.
Prior to Webb’s launch, only a handful of supernovae had been found above a redshift of 2, which corresponds to when the universe was only 3.3 billion years old — just 25% of its current age. The JADES sample contains many supernovae that exploded even further in the past, when the universe was less than 2 billion years old.
Previously, researchers used NASA’s Hubble Space Telescope to view supernovae from when the universe was in the "young adult" stage. With JADES, scientists are seeing supernovae when the universe was in its “teens” or “pre-teens.” In the future, they hope to look back to the “toddler” or “infant” phase of the universe.
To discover the supernovae, the team compared multiple images taken up to one year apart and looked for sources that disappeared or appeared in those images. These objects that vary in observed brightness over time are called transients, and supernovae are a type of transient. In all, the JADES Transient Survey Sample team uncovered about 80 supernovae in a patch of sky only about the thickness of a grain of rice held at arm’s length. [my highlight]
Pierel and other STScI researchers provided expert analysis to determine which transients were actually supernovae and which were not, because often they looked very similar. The team identified a number of high-redshift supernovae, including the farthest one ever spectroscopically confirmed, at a redshift of 3.6. Its progenitor star exploded when the universe was only 1.8 billion years old. It is a so-called core-collapse supernova, an explosion of a massive star. Image B: Jades Deep Field Transients (NIRCam) Uncovering Distant Type Ia SupernovaeThis is really our first sample of what the high-redshift universe looks like for transient science. We are trying to identify whether distant supernovae are fundamentally different from or very much like what we see in the nearby universe.
Justin Pierel,
NASA Einstein Fellow at the Space Telescope Science Institute (STScI)
Baltimore, Maryland, USA.
Of particular interest to astrophysicists are Type Ia supernovae. These exploding stars are so predictably bright that they are used to measure far-off cosmic distances and help scientists to calculate the universe's expansion rate. The team identified at least one Type Ia supernova at a redshift of 2.9. The light from this explosion began traveling to us 11.5 billion years ago when the universe was just 2.3 billion years old. The previous distance record for a spectroscopically confirmed Type Ia supernova was a redshift of 1.95, when the universe was 3.4 billion years old.
Scientists are eager to analyze Type Ia supernovae at high redshifts to see if they all have the same intrinsic brightness, regardless of distance. This is critically important, because if their brightness varies with redshift, they would not be reliable markers for measuring the expansion rate of the universe.
Pierel analyzed this Type Ia supernova found at redshift 2.9 to determine if its intrinsic brightness was different than expected. While this is just the first such object, the results indicate no evidence that Type Ia brightness changes with redshift. More data is needed, but for now, Type Ia supernova-based theories about the universe’s expansion rate and its ultimate fate remain intact. Pierel also presented his findings at the 244th meeting of the American Astronomical Society.
Looking Toward the Future
The early universe was a very different place with extreme environments. Scientists expect to see ancient supernovae that come from stars that contain far fewer heavy chemical elements than stars like our Sun. Comparing these supernovae with those in the local universe will help astrophysicists understand star formation and supernova explosion mechanisms at these early times.
We’re essentially opening a new window on the transient universe. Historically, whenever we've done that, we've found extremely exciting things — things that we didn't expect.
Matthew Siebert, STScI Fellow
Leader of the spectroscopic analysis of the JADES supernovae.Because Webb is so sensitive, it's finding supernovae and other transients almost everywhere it’s pointed. This is the first significant step toward more extensive surveys of supernovae with Webb.
Eiichi Egami, JADES team member
Research professor at the University of Arizona in Tucson.
By contrast, here is how the Bible describes the universe, which, according to creationists, is just a few thousand years old and was forged by their putative creator god to just look vast and old in order to fool us.
The Universe as described in Genesis 1: 3-18
And God said, Let there be light: and there was light. And God saw the light, that it was good: and God divided the light from the darkness. And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.
And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so. And God called the firmament Heaven. And the evening and the morning were the second day. And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so. And God called the dry land Earth; and the gathering together of the waters called he Seas: and God saw that it was good.
[…]
And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years: And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.
And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also. And God set them in the firmament of the heaven to give light upon the earth, And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.
And God said, Let there be light: and there was light. And God saw the light, that it was good: and God divided the light from the darkness. And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.
And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so. And God called the firmament Heaven. And the evening and the morning were the second day. And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so. And God called the dry land Earth; and the gathering together of the waters called he Seas: and God saw that it was good.
Gen 1:3-10
[…]
And God said, Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years: And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.
And God made two great lights; the greater light to rule the day, and the lesser light to rule the night: he made the stars also. And God set them in the firmament of the heaven to give light upon the earth, And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good.
Gen 1:14-18
And with the authors getting it so laughably wrong, and showing their parochial ignorance, what plausible reason is there to suppose they got anything else right? The idea is just too preposterous for words. If the Bible was discovered for the first time today, we could date it accurately to the Bronze/Early Iron Age by the scientific ignorance and naivety of the authors and place its authorship somewhere around the Middle East by the tribal, despotic brutality and casual misogyny that passes for morality, in it.
Its value is only as a reminder of what simple people from the fearful infancy of our species used to believe before we had science.
Ten Reasons To Lose Faith: And Why You Are Better Off Without It
This book explains why faith is a fallacy and serves no useful purpose other than providing an excuse for pretending to know things that are unknown. It also explains how losing faith liberates former sufferers from fear, delusion and the control of others, freeing them to see the world in a different light, to recognise the injustices that religions cause and to accept people for who they are, not which group they happened to be born in. A society based on atheist, Humanist principles would be a less divided, more inclusive, more peaceful society and one more appreciative of the one opportunity that life gives us to enjoy and wonder at the world we live in.
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