What Has the James Webb Space Telescope Discovered (So Far)?
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On December 25, 2021, NASA's James Webb Telescope was launched from the European Space Agency's Launch Center in French Guiana. After six months of testing and configuring the telescope, in July of 2022, its first images were transmitted. Since then, we have received a flood of images and data that have caused astronomers to rethink much of what we know about the universe.

Learn more about the discoveries made by the James Webb Space Telescope so far on this episode of Everything Everywhere Daily. This episode is sponsored by NerdWallet. When it comes to general knowledge and history, you know I've got you covered. But who do you turn to when you need smart financial decisions? If your answer is NerdWallet, then you're absolutely right. And if it's not, let me change your mind.

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Learn more at shopify.com/enterprise. I should start by noting that this episode is a follow-up to an episode I recorded back in December of 2021. That episode was recorded just before the James Webb Space Telescope was launched and deployed. And to recap, the Webb is the largest space telescope ever built. Its mirror has a diameter of 6.5 meters or 21.3 feet.

As a point of comparison, the Hubble Space Telescope has a diameter of 2.4 meters or 7.9 feet. So the total light gathering area of the web is 6.25 times greater than that of the Hubble. Whereas the Hubble is designed to observe in the visible part of the spectrum, the web is designed to observe in the infrared part of the spectrum. The reason why it was built to observe in the infrared part of the spectrum is because it's designed to observe some of the furthest objects possible in the universe.

The further away something is, the further back in time you're looking. As the universe is expanding, the light from these distant objects is being stretched into longer wavelengths. This is known as the redshift, and it's the light equivalent of the Doppler effect that you can hear when vehicles approach you and then drive away. The launch and deployment of the Webb was a very risky and intricate affair. The telescope had 344 single-point failures.

That means there were 344 things that if any one of them went wrong, would scuttle the entire mission. Unlike other space telescopes, the Webb is not in Earth orbit. Rather, it's located at a gravitationally stable point known as L2 or Lagrange Point 2, which is located at a point in space on the other side of the moon from the Earth. After years and years of planning, everything went perfectly.

NASA spent more than six months testing and tweaking the camera before it was ready to start making observations. I should note one other thing so that some of these observations make sense. Astronomy is a different type of science. If you really want to apply the scientific method properly, you develop a hypothesis and then you test it with an experiment.

But you can't really do that in astronomy. You can't build a star to see how it works. Instead, astronomy relies on observations. You can make a prediction, but then you have to find something to verify it. For example, this was the case with gravitational lensing. Albert Einstein first predicted that gravity could act like a lens to bend light in 1912. Decades after his prediction, in 1979, such an example was found.

Most of the time, astronomers will observe something and then develop a theory to try and explain it. And when they observe something that doesn't jibe with the theory, then the theory needs to be adjusted or replaced altogether. So, with that being said, what have astronomers discovered? Let's start with the big stuff. The web has peered back about as far as is possible and found something that shouldn't exist.

According to existing cosmological theories, the universe is about 13.787 billion years old. This is determined by the cosmic microwave background radiation and the universe's expansion rate, also known as the Hubble constant. We also have a theory for how galaxies and stars form and how long the process of formation takes. The galaxies that were observed were far larger and older than what we think should be possible going back that far.

By analyzing the light emitted from these galaxies, it was determined that they were viewing light that was emitted 500 to 700 million years after the Big Bang. Given how old they are and how much time had elapsed since the Big Bang, these galaxies shouldn't be that big. And perhaps more importantly, the red stars in the galaxy shouldn't be that old.

Previous observations by the Hubble have found blue stars in distant early galaxies. Blue stars are younger because they have more mass and burn hotter. They expected galaxies with about a billion solar masses, but they ended up finding some with 50 billion solar masses. As of now, there is no consensus explanation for these observations, but several theories have been put forward.

One is that the process of galactic formation in the early universe was either different than it is today, or some other variable, such as a large black hole in the center of the galaxy, accelerated the formation of galaxies. Another theory holds that we underestimated how quickly stars formed in the early universe. If stars formed in massive bursts shortly after the Big Bang, this could lead to the rapid evolution of galaxies, making them appear more mature at earlier times than our models predict.

Another theory is that perhaps physics just worked differently in the early universe. Yet another theory is reviving an older idea known as tired light. This theory, which challenges the concept of cosmic expansion causing redshift, posits that photons lose energy over time due to interactions with other particles or with space itself. If this is true, this could mean that the universe's age has been underestimated because we've misinterpreted redshift.

Some estimates suggest that the universe could be 26.7 billion years old, removing the need for dark matter by altering how we understand the expansion of the universe and light's behavior. And of course, we can't rule out the possibility of simple errors in measurement and observation. We have no clue what the answer is at this moment, but resolving these discrepancies is going to be one of the hottest areas of cosmological research over the next several years.

Another area where the web has made exciting new discoveries is in the area of exoplanets. If you remember back to my episode on exoplanets, the vast majority of the 5,765 known exoplanets, as of the time of this recording, have been discovered by their influence on the star they orbit. Either the gravity of the planet causes the star to wobble, or it slightly dims the light coming from the star when it passes in front of it.

Given how powerful the web is, it's able to do something that hasn't been done before. It can directly analyze the atmosphere of some exoplanets. Of particular interest was planet WASP-39b. The planet was first discovered in 2011, and it was a high priority for the web to look at. Webb analyzed the planet's light spectrum and determined that it had water, carbon dioxide, sodium, and sulfur dioxide in its atmosphere.

WASP-96b is a planet that's about half the mass of Jupiter that orbits its star at one-ninth the distance that Mercury does the Sun. The web found out that it had water in its atmosphere and that it probably has clouds and hazes in its atmosphere as well.

Water isn't the only type of cloud that was found. Exoplanet VHS 1256 b showed signs of silicate clouds and a variety of organic compounds, including carbon dioxide, water, methane, and carbon monoxide, suggesting a dynamic and potentially rich atmospheric chemistry. VHS 1256 b is actually closer to a brown dwarf than a planet. It's huge, but it isn't big enough to start fusion and become a star.

The silicate clouds in its atmosphere might actually be a type of liquid sand. One of the reasons VHS 1256b could be observed so well is that, unlike many exoplanets that orbit close to their star, this one is four times the distance from its star than Pluto is from our Sun. And it's 19 times as massive as Jupiter. Its distance means that it could be observed without the bright light of its star overwhelming the observation.

The very first exoplanet that the Webb discovered was LHS 475b. What makes this planet so special is that its diameter is 99% that of Earth's, and its mass is approximately 91%. Unfortunately, it probably isn't a good candidate for future colonization. It has a surface temperature of around 313 Celsius, and it orbits its star every two days.

The Webb isn't just observing fully formed stars and exoplanets. It has also made observations of stars that are in the process of forming. By studying the disks around young stars where planets are believed to form, the Webb has provided insights into the initial stages of planet formation. Observations of these protoplanetary disks reveal the presence of chemicals that are necessary for life.

The molecular cloud, known as Chameleon 1, about 500 light-years from Earth, has been found to contain carbon, oxygen, hydrogen, nitrogen, and sulfur. The infrared camera on the web has been able to see some things that other telescopes simply can't. In the constellation Cetus, there are two galaxies that are in the middle of colliding. Known as IC 1623, it's been obscured by the enormous amounts of dust.

Webb, however, can peer through the dust in infrared wavelengths, and it has observed that the colliding galaxies are forming new stars at an accelerated pace. One particularly bright section is making stars at 20 times the rate of the Milky Way. The Webb has also found an entirely new class of object which have been dubbed JUMBOs, which stand for Jupiter Mass Binary Objects. Webb has found 40 pairs of JUMBOs so far, and they share one remarkable trait.

None of them orbit a star. The fact that such large planet-type objects can exist outside of the orbit of a star has changed many of our ideas of planet formation. While the major focus of the web has been making observations at the edge of the known universe, it's also made some observations in our solar system. Titan, the largest moon of Saturn, is one of the most intriguing moons on the solar system for one reason: Titan has an atmosphere. In fact, it has a relatively thick atmosphere.

It's believed that on Titan, it is the only place in the solar system other than Earth that you could walk around without a pressurized suit. You'd still certainly need protection from the incredibly low temperatures and the toxic atmosphere, but you wouldn't need pressure. Or at least not very much. On November 4th, 2022, Webb captured an image of Titan that showed clouds in its atmosphere.

Two days later, the Keck Observatory in Hawaii captured an image of Titan that showed that the clouds that were seen by the Webb Telescope had moved. There was weather on Titan. On top of all the discoveries I've just mentioned, there are many, many more observations that have been made by the Webb Telescope so far. And all of this has been done in just under two and a half years.

NASA traditionally has very conservative estimates for the duration of its unmanned missions, but they often surpass those estimates by years. For example, the Opportunity rover on Mars was only scheduled for 90 days, but it ended up being operational for 14 years. The Webb mission had an initial span of just five and a half years. However, because of the amount of propellant on board, it's entirely possible that the Webb could be operational for another 20 years.

Assuming it continues to function, and based on previous NASA missions, this is highly likely. So there should be a lot more discoveries made by the James Webb Telescope. And some of those may require astronomers to reconsider what we know about the universe. The executive producer of Everything Everywhere Daily is Charles Daniel. The associate producers are Benji Long and Cameron Kiefer.

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