Graphic on the different types of "exoplanets" which the new James Webb telescope will be investigating to determine the composition of their atmospheres and the presence of water. Posted on 07/14/2022 4:05:41 PM PDT by LibWhacker
Graphic on the different types of "exoplanets" which the new James Webb telescope will be investigating to determine the composition of their atmospheres and the presence of water.
The first stunning images from the James Webb Space Telescope were revealed this week, but its journey of cosmic discovery has only just begun.
Here is a look at two early projects that will take advantage of the orbiting observatory's powerful instruments.
The first stars and galaxies
One of the great promises of the telescope is its ability to study the earliest phase of cosmic history, shortly after the Big Bang 13.8 billion years ago.
The more distant objects are from us, the longer it takes for their light to reach us, and so to gaze back into the distant universe is to look back in the deep past.
"We're going to look back into that earliest time to see the first galaxies that formed in the history of the universe," explained Space Telescope Science Institute astronomer Dan Coe, who specializes in the early universe.
Astronomers have so far gone back 97 percent of the way back to the Big Bang, but "we just see these tiny red specks when we look at these galaxies that are so far away."
"With Webb, we'll finally be able to see inside these galaxies and see what they're made of."
While today's galaxies are shaped like spirals or ellipticals, the earliest building blocks were "clumpy and irregular," and Webb should reveal older redder stars in them, more like our Sun, that were invisible to the Hubble Space Telescope.
Coe has two Webb projects coming up—observing one of the most distant galaxies known, MACS0647-JD, which he found in 2013, and Earendel, the most distant star ever detected, which was found in March of this year.
Webb will turn its instruments on distant stars like Earendel, seen in here in an image taken by Hubble.
While the public has been enticed by Webb's stunning pictures, which are shot in infrared because light from the far cosmos has stretched into these wavelengths as the universe expanded, scientists are equally keen on spectroscopy.
Analyzing the light spectrum of an object reveals its properties, including temperature, mass, and chemical composition—effectively, forensic science for astronomy.
Science doesn't yet know what the earliest stars, which probably started forming 100 million years after the Big Bang, will look like.
"We might see things that are very different," said Coe—so-called "Population III" stars that are theorized to have been much more massive than our own Sun, and "pristine," meaning they were made up solely of hydrogen and helium.
These eventually exploded in supernovae, contributing to the cosmic chemical enrichment that created the stars and planets we see today.
Some are doubtful these pristine Population III stars will ever be found—but that won't stop the astronomical community from trying.
Anyone out there?
Astronomers won time on Webb based on a competitive selection process, open to all regardless of how advanced they are in their careers.
Graphic on the James Webb space telescope. which began releasing a new wave of cosmic images.
Olivia Lim, a doctoral student at the University of Montreal, is only 25 years old. "I was not even born when people started talking about this telescope," she told AFP.
Her goal: to observe the roughly Earth-sized rocky planets revolving around a star named Trappist-1. They are so close to each other that from the surface of one, you could see the others appearing clearly in the sky.
"The Trappist-1 system is unique," explains Lim. "Almost all of the conditions there are favorable for the search for life outside our solar system."
In addition, three of Trappist-1's seven planets are in the Goldilocks "habitable zone," neither too close nor too far from their star, permitting the right temperatures for liquid water to exist on their surface.
The system is "only" 39 light year away—and we can see the planets transit in front of their star.
This makes it possible to observe the drop in luminosity that crossing the star produces, and use spectroscopy to infer planetary properties.
It's not yet known if these planets have an atmosphere, but that's what Lim is looking to find out. If so, the light passing through these atmospheres will be "filtered" through the molecules it contains, leaving signatures for Webb.
The jackpot for her would be to detect the presence of water vapor, carbon dioxide and ozone.
Trappist-1 is such a prime target that several other science teams have also been granted time to observe them.
Finding traces of life there, if they exist, will still take time, according to Lim. But "everything we're doing this year are really important steps to get to that ultimate goal."
Minor point... Even if it is infinitely large it can have a shape. For instance, A sphere with an infinitely long spike, or spikes, on it.
Hmm, I know it’s a joke, but it must be the same as the speed of light... Let’s say you switch off A laser beam. The tail end of the beam continues to travel outward at the speed of light, followed by dark, which cannot overtake it. Therefore, it’s traveling at the same speed. Doncha just LOVE physics?!!
Just as I figured. A non response.
Anyway, speed of light is a convention, agreed upon by international standards.
Why? Because you can’t use two clocks, due to issues with physics and relativity. Can’t use one clock because then it is an average. An average of two legs means neither one leg can be known, but they add up to a cumulative elapsed duration.
So, being unable to determine a one way leg, the duration of either individual leg is impossible to know, except by averaging.
0+8/2=4, 3+5/2=4, 6+2/2=4 solution is 4.
Replace any speed of light system, radar, for example, with any solution for a two way duration and it works.
But, anyway.
Regards
In the old days I would turn off the tube tv and watch the light shrink to a dot then disappear slowly.
I am also baffled by the new laws of physics. Such as - If Joe Biden, a communist, a pedophile, and a pervert enter a bar for the duration and only one comes out at closing time - How can this be?
We don’t really exist-We are only perturbations in the higgs field.
“Anyway, speed of light is a convention, agreed upon by international standards.”
ROTFLMAO!
A second is convention based on the measured speed of light.
A meter is convention based on the measured speed of light.
You should get a beer for your work in this thread. Just incredible.
TY
Look up Einstein’s opinion in 1908....
It is all workable solutions. None absolute.
I noticed you didn’t try to refute my claim that the one way speed of light is currently undetermined.
I have no idea what you are referring to.
“I noticed you didn’t try to refute my claim that the one way speed of light is currently undetermined.”
I said you should do your homework.
Been studying.
I restated:
Question: what is the one way speed of light?
Answer: not only unknown, but undefined.
Rebut?
Now they only need to figure out God Speed.
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