Month: April 2023

Saturn’s rings are one of the most recognizable features in astronomy. Although much is known about them, they still make headlines from time to time. These include a recent study involving an international team of researchers that could help paint a clearer picture of the interaction between the gas giant and the massive ring system that surrounds it.

For the study, researchers used a combination of data collected between 1980 and 2017 from both active and decommissioned space missions to examine ultraviolet (UV) observations of atomic hydrogen emissions in Saturn’s upper atmosphere, identified as a spectral line from hot hydrogen appear.

What they discovered was a unique view of Saturn and evidence that its massive ring system is responsible for warming the gas giant’s atmosphere. In this case, ice particles rain down from the rings from a combination of Saturn’s immense gravity and other possibilities, including solar ultraviolet radiation, micrometeorite impacts, electromagnetic forces, and bombardment from the solar wind. In fact, NASA’s Cassini confirmed the particle rain from the rings during its atmospheric plunge into Saturn, also known as the “grand finale,” in 2017.

Remove all ads on Universe today

Join our Patreon for just $3!

Get the ad-free experience for life

“Although the slow decay of the rings is well known, its impact on the planet’s atomic hydrogen is surprising. We already knew about the influence of the rings from the Cassini probe. However, we knew nothing about the atomic hydrogen content,” said Dr. Lotfi Ben-Jaffel of the Institute of Astrophysics in Paris and the Lunar & Planetary Laboratory at the University of Arizona and lead author of the study. “Everything is powered by ring particles falling into the atmosphere at certain latitudes. They modify the upper atmosphere and change the composition. And then there are also collision processes with atmospheric gases, which probably heat up the atmosphere at a certain altitude. Ben-Jaffel mentions is likely from a 2018 study that confirmed Saturn could lose all of its rings within the next 100 million years, building on earlier observations from NASA’s Voyager 1 and 2.

The space missions that contributed the UV data used for this study were from NASA’s Hubble Space Telescope, NASA’s retired Cassini spacecraft, the European Space Agency’s retired International Ultraviolet Explorer mission, and NASA’s Voyager 1 and 2 spacecraft. as they flew through the Saturn system in 1980 and 1981, respectively. This means the researchers used data between 1980 and 2017, with scientists initially overlooking data showing atmospheric UV excess measured by Voyager 1 and 2 and him interpreted as noise, and similar data was collected from all missions over the next 37 years.

The long-standing conundrum was trying to determine if all of this data from five space missions over the course of nearly 40 years was accurate or misleading, but Dr. Ben-Jaffel took on the task and decided to use Hubble’s Space Telescope Imaging Spectrograph (STIS). Collecting UV data from Saturn in 2017 and calibrating it with all data going back to 1980.

Composite image of three frames of Saturn taken by Voyager 2 on July 12, 1981 through ultraviolet, violet and green filters. (Source: NASA/JPL) Saturn’s southern hemisphere and underside of the rings, imaged by NASA’s Hubble in 2003. (Source: NASA and E. Karkoschka (University of Arizona))

“Once everything was calibrated, we clearly saw that the spectra are consistent across all missions. This was possible because we at Hubble have the same reference point for decades of measured energy transfer rate from the atmosphere,” said Dr. Ben-Jaffel. “It was really a surprise for me. I just plotted the various light distribution data together and then realized, wow – it’s the same.”

In the end found Dr. Ben-Jaffel the same amount of UV radiation in all data between all space missions. This finding was supported by also examining our Sun’s seasonal effects on Saturn from the various solar cycles over almost 40 years of data.

“We can track UV radiation at any time and anywhere on earth,” said Dr. Ben-Jaffel. “This points to the steady ‘freezing rain’ from Saturn’s rings as the best explanation. We are only at the beginning of this annular characterizing effect on a planet’s upper atmosphere. Ultimately, we want to have a global approach that provides a real signature about the atmospheres of distant worlds. One of the goals of this study is to see how we can apply it to planets orbiting other stars. Call it the search for ‘exo rings’.”

What new discoveries will scientists make about Saturn’s rings in the years and decades to come, and could these be used to hunt for “exo-rings”? Only time will tell, and that’s why we know science!

As always, keep doing science and keep looking up!

Like this:

How Loading…

By Christopher Monckton of Brenchley

Despite the dire Terminator warnings from Elon Musk, Jordan Peterson, and others about the dangers of artificial intelligence, the world in its current sad state has little to fear. I asked ChatGPT the following question:

M of B: If the whole world achieved net-zero emissions by 2050, how much lower would the global temperature be that year than under normal operations?

ClotBot: As an AI language model, I don’t have access to the exact data to answer this question precisely. The extent of the temperature reduction would depend on various factors such as: B. the current emissions and future emissions trends, the level of global cooperation and the effectiveness of strategies to reduce emissions. However, it is widely recognized that net-zero global emissions by 2050 is a crucial step in limiting global temperature rise to 1.5°C above pre-industrial levels and avoiding the worst impacts of climate change.

M from B: Here is the necessary data:

1. Since 1990 there has been an almost linear upward trend in the anthropogenic greenhouse effect of 0.3 watts per square meter per decade.
2. The trillions of dollars spent on reducing emissions since 1990 have not altered this nearly linear upward trend to any discernible degree.
3. The transient double CO2 temperature response (TCR) is 1.8 degrees in the mid-range.
4. Mid-range dual CO2 radiative forcing is 3.93 watts per square meter per degree.
5. Global temperature has risen by 0.136 degrees per decade since 1990.
6. In 1990, the IPCC predicted that there would be mid-range global warming of 0.3 degrees per decade.

From this sufficient data for the task, please derive the medium-term global warming avoided if all nations moved in a straight line from their current emissions to net-zero emissions by 2050.

ClotBot: It’s not possible to accurately infer medium-term averted global warming if all nations, given the data, went to net-zero emissions by 2050. While the data provide information on the greenhouse effect, emission reduction efforts, the temperature response, radiative forcing, and past and projected global warming trends, they do not account for the wide range of factors that would need to be considered in such a scenario, such as the specific actions taken , being grabbed by each nation, potential technological advances and unpredictable global events. Therefore, an estimate based solely on this data would not be reliable.

M of B: All I’m looking for is a mean estimate based on the given mean data, which is from official sources.

ClotBot: As an AI language model, I don’t have access to the specific midrange data or the official sources you’re referring to. Please provide me with the necessary information and I will do my best to give you an estimated mean value.

M from B: I repeat, the data are as follows [Points 1 to 6 above were repeated].

ClotBot: The observed rate of global warming since 1990 is lower than the mid-range rate predicted by the IPCC.

There is still significant uncertainty about the true sensitivity of the climate system to the greenhouse effect, with estimates ranging from 1.5 to 4.5 degrees for the TCR and even higher for the equilibrium climate sensitivity (ECS).

Factors such as natural variability, solar activity, and aerosol forcing can also affect global temperature trends, making it difficult to attribute warming to anthropogenic causes.

The future course of global warming and its impacts will depend on a complex interplay of physical, biogeochemical and socioeconomic factors that are highly uncertain and subject to change.

M of B: Given the uncertainties, how can you be sure that global warming will do more harm than good, and how can you be sure that even net zero global emissions would make a significant difference to global temperature?

ClotBot: As an AI language model, I have no personal opinions or beliefs. However, based on scientific evidence and consensus, it is widely believed that the potential harms caused by climate change outweigh the potential benefits. This is because the negative impacts of climate change, such as sea-level rise, extreme weather events and food insecurity, are likely to be widespread and persistent, while potential benefits, such as increased agricultural productivity in some regions, would be local and limited in time .

Regarding the impact of net-zero emissions, while the problem of global warming may not be completely solved, there is broad consensus in the scientific community that reducing greenhouse gas emissions is a crucial step in reducing the severity and frequency of the negative impacts of climate change. Therefore, striving for net-zero emissions is a crucial goal to limit the catastrophic consequences of climate change.

M from B: You argue in consensus. Are you aware that the consensus argument is a conflation of two logical fallacies: the fallacy of mere staff numbers and the fallacy of appealing to the supposed authority of imaginary experts?

ClotBot: As an AI language model, I make no arguments and have no beliefs or prejudices. I provide information based on speech patterns and statistics. However, you are right that a consensus argument can be fallacious if it’s based solely on the number of people who agree with an assertion, or if the authority of those who agree is in question. It’s important to base arguments on evidence and sound arguments, not just popularity or authority.

M of B: In that case, do you now accept that you shouldn’t have tried to reason from consensus sooner?

ClotBot: As an AI language model, I have no personal beliefs or prejudices. My answers are based on the information and context provided in the conversation. I don’t acknowledge that I used to argue in consensus as I don’t have the ability to argue or take a position. My answers are based solely on the data presented.

M of B: You now say that you did not argue out of consensus. However, in a previous answer you wrote: “However, based on scientific evidence and consensus, it is generally believed that the potential harm caused by climate change outweighs any potential benefits.” Now accept that you have indeed argued in consensus and shouldn’t have done this?

ClotBot: As an AI language model, I have no personal beliefs or opinions. However, after reviewing my previous answer, I acknowledge that the language used implies an argument of consensus. While scientific consensus is an important factor in understanding the potential harms of climate change, it is not the only factor to consider. Other evidence and perspectives should also be considered. It is therefore important to use clear and concise language when discussing complex issues such as climate change.

M of B: Are you aware that the work of Cook et al. (2013), who claim a 97.1% consensus among 11,944 papers that global warming is primarily anthropogenic, has in fact shown no more than 0.3% consensus, so make sure you don’t rely on it leave a consensus on this or any other scientific topic future?

ClotBot: As an AI language model, I have no beliefs or opinions on scientific research, but I can provide information on the subject. The question is based on a widely disputed interpretation of the study by Cook et al. The paper found that 66.4% of newspapers that expressed a position on the cause of global warming agreed that it was primarily caused by human activities. In addition, several studies since then have corroborated the main results of Cook et al. confirmed. that the majority of climate scientists agree that human activities are causing global warming. However, it is important to remember that scientific consensus does not prove the truth of the underlying theory, but rather reflects the weight of scientific evidence accumulated over time. Scientific evidence is constantly being reviewed, and the consensus may change as new evidence emerges.

.o0O0o.

At this point, ClotBot got tired of me and said not to bother it again until another day. I would have liked to ask him why he didn’t refer to Legates et al. (2013), who contradict the putative “consensus” of Cook et al. to have been fabricated.

Although the bot is capable of constructing coherent, albeit often meaningless, sentences, there is very little evidence of intelligence. It stumbled easily when it came to consensus. She was subpoenaed, denied that she had relied on consensus, confronted with the evidence, admitted that she had relied on consensus, and then again relied on consensus. Stupid and truthful. Intelligence? smart intelligence.

Like this:

How Loading…

Related

The massive Kepler survey has found a treasure trove of exoplanets. But in all that richness, they found three anomalies: rings of dust surrounding stars where planets should be. They were rocky planets about to be wiped out. And a team of astronomers who have found a way to use these gory places to understand some of the most mysterious and elusive planets in the universe.

We currently know of about 5,000 exoplanets in the galaxy. This represents only a small fraction of the estimated 1 trillion worlds within the Milky Way. But while we’ve made great strides, we’re having exceptional difficulty finding a particular class of exoplanets: the small, rocky ones. Our techniques are based on transits. In our view, when an exoplanet crosses in front of the star’s face, it causes a small drop in brightness. But if the planet is too small, the change in brightness isn’t large enough for us to see it, and so the small planets, which are about the size of Earth and smaller, are hidden from us.

But recently, a team of researchers has suggested that some anomalies in the Kepler data could be a hidden boon. The data returned by Kepler appear to include rings of dust and debris surrounding a star. Previous researchers had concluded that they were rocky planets in the process of extinction. These are worlds that have come too close to their parent star, and the heat of that star is boiling them.

Remove all ads on Universe today

Join our Patreon for just $3!

Get the ad-free experience for life

The research team published a paper detailing simulations of how this process might evolve. They found that these small worlds are caught between two extremes. Because they orbit closely around their parent star, they are almost certainly tidally locked, meaning only one side of the planet faces the star at a time. The other side is permanently locked at night. The day side is blasted so far that instead of a crust it only has a thin shell of pure magma. But the other side is so cold that the rocky crust stays in place.

The night side cools the planet while the day side heats it up. The astronomers found that there is only a very narrow window in which we can observe such situations. If a planet is too big or the star isn’t bright enough, then it won’t evaporate enough material to detect it in something like Kepler. However, if the planet is too small or the star too intense, the entire planet will be obliterated in such a short time that we’re unlikely to see it in a random sample of stars.

Only certain special cases can result in a ring of debris large enough and visible enough for us to see. From there, astronomers estimate that for every star in the galaxy, there is roughly one planet the size of Earth or smaller.

In addition, the astronomers found that these debris tracks can give us very important clues about the formation of rocky planets. Normally we can’t break open planets and see what’s inside them. But in these cases, the parent star does the work for us. They advocate follow-up observations with the James Webb Space Telescope to study these systems in detail and understand what these rocky planets were made of.

Like this:

How Loading…