Astronomy

Companies attract venture funding for redesigned psychedelic drugs

On June 21, 2004, SpaceShipOne reached the final frontier for the first time, notching a huge milestone for private spaceflight and paving the way for space tourism.

What happens if a star gets too close to a black hole?

This colorized and digitally sharpened image of the Sun is composed of

Boeing's Starliner capsule will remain docked with the ISS until at least July 2, in part to give mission team members more time to assess helium leaks and thruster issues.

Mars holds a very special place in our hearts. Chiefly because of all the other planets in the Solar System Mars is probably the place we are going to find some tantalising clues or maybe even evidence of prehistoric life. NASA Perseverance Rover has been trundling around the Jezero Crater looking for evidence that it was once hospitable to life. To that end it has not only been collecting rock samples but air samples too and scientists can’t wait to get their hands on them. 

The Mars Perseverance Rover is part of NASA’s Mars 2020 mission. It launched on 30 July 2020 and landed in the Jezero Crater successfully on 18 February 2021. The site was picked because it’s a dried up river bed and if there is any evidence of ancient primitive life on Mars, it is a likely location. Perseverance is equipped with a host of instruments including a drone named Ingenuity to survey the planet. 

Mars Perseverence rover sent back this image of its parking spot during Mars Solar Conjunction. Courtesy NASA/JPL-Caltech

One exciting element of the mission is the collection of rock samples as part of the Mars Sample Return Campaign. Twenty four core samples have been collected to date and deposited on the surface ready for collection by a future mission. It’s not just rock samples that have been collected though. Known as ‘headspace’ there is air in the space around the rock samples and it is this that has got scientists excited. 

Not only do the rocks hold secrets about Mars but the atmosphere does too. It’s an atmosphere rich in Carbon Dioxide but is expected to have trace amounts of other gasses  too. Information about the current climate can be gained from the trapped gasses but it’s also possible to learn about the evolution of the atmosphere through analysis of the rocks. There is one particularly important tube that has been filled entirely with gas from the atmosphere. 

Image of the Martian atmosphere and surface obtained by the Viking 1 orbiter in June 1976. (Credit: NASA/Viking 1)

With the sample sat on the surface of Mars potentially for many years, the gas trapped will interact with the rock in the sample tube. It will only be when the tubes are opened up when they arrive back here on the Earth that the interaction will cease. It’s hoped to understand more about the levels of water vapour near the Martian surface. 

It isn’t just the water vapour that is of interest but the levels of trace gas too are of interest. Through analysing the gas samples we can tell if there are gasses like neon, argon and xenon which are non reactive gasses. Because these gasses do not react then there presence in the tube samples may suggest that Mars stated with an atmosphere. We know that it had a much thicker atmosphere in the past but we don’t know whether it has always been there or whether it developed later.  

There are many benefits that will come from analysing the samples even, the prevalence of dust that will help future human exploration. As Justin Simon from NASA’s Johnson Space Center in Houston said “The gas samples have a lot to offer Mars scientists, even those who don’t study Mars would be interested because it will shed light on how the planet forms and evolves.”

Source : Why Scientists Are Intrigued by Air in NASA’s Mars Sample Tubes

The post It’s Not Just Rocks, Scientists Want Samples Mars’s Atmosphere appeared first on Universe Today.

A spinning magnetic wind blows from supermassive black holes, paving the way for more matter to fall into them, scientists say.

Some scientists believe they may be able to find buried liquid water on the Red Planet by studying seismic and magnetic readings to reconstruct the aftermath of marsquakes.

The Gaia space telescope has spotted the dim companions of eight bright stars, suggesting we can expect new glimpses of distant planets.

The long-term economic effects of tropical cyclones far outweigh the direct damages from high winds and flooding, with local incomes declining for years after the storm hits

The long-term economic effects of tropical cyclones far outweigh the direct damages from high winds and flooding, with local incomes declining for years after the storm hits

A SpaceX Falcon Heavy is scheduled to launch NOAA's GOES-U weather satellite on June 25. Here's how to watch live.

The Earth-sized storm on Jupiter known as the red spot was thought by many to have been first observed in 1665, but it turns out that may have been an entirely different enormous storm, with today's storm dating back only to 1831

The Earth-sized storm on Jupiter known as the red spot was thought by many to have been first observed in 1665, but it turns out that may have been an entirely different enormous storm, with today's storm dating back only to 1831

The Crab Nebula has always fascinated me, albeit amazed me that it doesn’t look anything like a crab! It’s the result of a star that exploded at the end of its life back in 1054 CE, leaving behind what is known as a supernova remnant. Back then the explosion would have been visible to the naked eye, even in daytime. It was thought that the supernova that led to the cloud was from a less evolved star with a core made from oxygen, neon and magnesium. Recent studies by the James Webb Space Telescope reveals that it may actually be the core collapse of an iron rich star. 

The Crab Nebula can be found in the constellation Taurus measuring 11 light years across. Deep inside the cloud, which expands at a rate of 1,500 kilometres per second, lies a rapidly rotating neutron star known as a pulsar. It emits a beam of electromagnetic radiation that sweeps across space much like a lighthouse sweeping out across the ocean. It has been the subject of many studies to learn about the dynamics of stellar evolution. 

Previous studies have attempted to understand the total kinetic energy of the original explosion based upon the velocity of the expanding cloud. The data suggested that the supernova was relatively low energy so the progenitor star was likely to be in the range of 8 to 10 times the mass of the Sun. If it had been more massive it would have experienced a more violent supernova which would be revealed in higher velocity of the expanding gas cloud. But there was a problem. 

The Fred Lawrence Whipple Observatory’s 48-inch telescope captured this visible-light image of the Pinwheel galaxy (Messier 101) in June 2023. The location of supernova 2023ixf is circled. The observatory, located on Mount Hopkins in Arizona, is operated by the Center for Astrophysics | Harvard & Smithsonian. Hiramatsu et al. 2023/Sebastian Gomez (STScI)

The observations of the Crab Nebula, particularly the high rotational speed of the pulsar, seemed to conflict with current supernova theory. In the model for lower mass stars like that which was the progenitor star of the Crab Nebula, the oxygen in the core ignites as the core collapses. This process does not have sufficient energy to generate such a fast rotating pulsar. 

A team of astronomers have addressed this curiosity using MIRI (Mid-Infrared Instrument) and NIRCam (Near-Infrared Camera) onboard the James Webb Space Telescope to collect data from the Crab Nebula. The team was led by Tea Temim from the Princeton University in New Jersey. They report that the gas composition of the cloud suggests the star may have been more evolved with some iron in the core which could have led to a higher energy supernova than previously thought.

Artist impression of the James Webb Space Telescope

With Webb’s sensitive infrared instruments, the iron and nickel emission lines can be seen with more clarity than ever before. Studying the bright lines in the spectrum of the nebula has allowed a much more reliable estimate of the iron and nickel ratio to be deduced. They found it was a higher percentage compared to the Sun which was expected for a more energetic supernova. 

The results are promising but the readings were taken from two small regions of the nebula so to rule out variations across the entire 11 light years further readings are needed. If the data from Webb is representative from the entire nebula then it’s possible one of the mysteries of the nebula may finally be solved.

Source  : Investigating the Origins of the Crab Nebula With NASA’s Webb

The post Something’s Always Been Off About the Crab Nebula. Webb Has Revealed Why! appeared first on Universe Today.

Lynn Conway, a trans woman and advocate for LGBTQ rights, was underappreciated and often underrecognized for her work in chip design

The rotation of Earth's inner core began to slow down more than a decade ago, altering the length of our days by fractions of a second.

Historians have claimed the people of Easter Island overexploited natural resources, causing a population crash, but new evidence suggests they lived sustainably for centuries

Historians have claimed the people of Easter Island overexploited natural resources, causing a population crash, but new evidence suggests they lived sustainably for centuries

Distant Titan is an oddball in the Solar System. Saturn’s largest moon—and the second largest in the entire Solar System—has an atmosphere denser than Earth’s. It also has stable lakes and seas of liquid hydrocarbons on its surface.

New research shows that waves on these seas are eroding Titan’s coastlines.

The research is “Signatures of Wave Erosion in Titan’s Coasts,” and it’s published in Science Advances. The lead author is Rose Palermo, an MIT graduate and research geologist at the U.S. Geological Survey.

In 2007, the Cassini spacecraft spotted lakes and seas of liquid hydrocarbons, mostly methane and ethane, on Saturn’s moon Titan. Titan and Earth are the only two bodies in the Solar System known to have surface liquids. Scientists have only Cassini data from Titan to work with, and they’ve been poring over the data in an effort to understand this strange world.

The moon’s seas are one of the most intriguing features throughout the entire Solar System. But they’re difficult to observe because of the thick atmosphere. Researchers have wondered if waves shape the coastlines, but there are conflicting signs about the nature of the seas. They could be rough, or they could be smooth. A paper from 2014 suggested that transient features in Titan’s northern sea, Ligeia Mare, could be waves.

But there’s no certainty.

“We found that if the coastlines have eroded, their shapes are more consistent with erosion by waves than by uniform erosion or no erosion at all.”

Rose Palermo, lead author, U.S. Geological Survey

“Some people who tried to see evidence for waves didn’t see any, and said, ‘These seas are mirror-smooth,'” lead author Palermo said in a press release accompanying the research. “Others said they did see some roughness on the liquid surface but weren’t sure if waves caused it.”

It seems likely that there would be waves on Titan. To investigate this question, researchers at MIT compared Titan’s shorelines to shorelines on Earth to see if they match.

The seas and lakes on Titan look much like some on Earth. They appear to be flooded valleys and depressions. But scientists are uncertain if these bodies of water are eroding their coastlines like those on Earth. “Spacecraft observations and theoretical models suggest that wind may cause waves to form on Titan’s seas, potentially driving coastal erosion, but the observational evidence of waves is indirect, and the processes affecting shoreline evolution on Titan remain unknown,” the authors write in their paper.

The problem is that there’s no reliable way to connect shoreline morphology directly to the mechanisms that shape it, even on Earth. To try to understand how erosion affects Titan’s coastlines, the researchers started with Earth. They examined how different coastal erosion mechanisms shape Earth’s coastlines, then applied the framework to Titan.

There are basically two types of coastal erosion: wave-driven erosion and uniform erosion. Each type produces different coastlines.

Wave erosion is driven by wind and produces a change proportional to the strength of the waves. Waves are usually stronger the farther they travel before they hit a coast. Wave erosion creates long, smooth stretches of coast where the coast is fully exposed and bays in protected areas where less erosion occurs. The distance the wind can blow to generate waves on a particular water body before striking a coast is called ‘fetch.’

“Wave erosion is driven by the height and angle of the wave,” Palermo explained. “We used fetch to approximate wave height because the bigger the fetch, the longer the distance over which wind can blow and waves can grow.”

Uniform erosion is different. It doesn’t rely on mechanical wave action. The compositional differences between Earth and Titan are apparent when it comes to uniform erosion. “Titan’s crust consists mainly of water ice, but its surface solids may also include heavy hydrocarbon molecules, such as benzene, that are soluble in liquid methane and ethane, such that the liquid lakes and seas may slowly dissolve the solid coasts of the north polar terrain,” the authors explain in their research.

Over a long enough period of time, uniform erosion occurs at the same rate in all locations, producing distinct morphological features: shorelines that are generally smooth even inside bays with sharp headlands that punctuate them.

“Here, we test the hypothesis that coastal erosion has shaped Titan’s seas by investigating whether coastline shapes are most consistent with wave-driven erosion, uniform erosion, or no coastal erosion,” the authors write.

This figure from the research illustrates how the two types of erosion would shape shorelines. The images are based on simulated Titan landforms and shorelines. A shows the initial condition of Titan’s water bodies, where rivers carved out channels, and rising seas flooded them. B shows the morphology that wave erosion would produce, where the erosion rate depends on fetch. C shows the morphology that Uniform erosion would produce, where the erosion is uniform in all locations. Darker blue indicates deeper water and lighter yellow indicates higher land. Image Credit: Palermo et al. 2024.

The different morphological features produced by wave-driven erosion and uniform erosion are obvious. Wave-driven erosion tends to smooth exposed sections of the coastline where fetch is large and preserve the coastline where fetch is small inside embayments.

Uniform erosion is different. It widens embayments and smooths out small-scale roughness on the coastline regardless of fetch. Headlands are the exception, which sharpen into thick-necked points that stick out into the main basin.

“We had the same starting shorelines, and we saw that you get a really different final shape under uniform erosion versus wave erosion,” said co-author Taylor Perron, Professor of Earth, Atmospheric and Planetary Sciences at MIT. “They all kind of look like the Flying Spaghetti Monster because of the flooded river valleys, but the two types of erosion produce very different endpoints.”

Titan’s Ligeia Mare is the second largest liquid body on Titan. The researchers say that its coastline appears to be altered by wave-driven erosion. Image Credit: By NASA/JPL-Caltech/ASI/Cornell – http://photojournal.jpl.nasa.gov/catalog/PIA17031, Public Domain, https://commons.wikimedia.org/w/index.php?curid=26294960

“We found that if the coastlines have eroded, their shapes are more consistent with erosion by waves than by uniform erosion or no erosion at all,” Perron said.

But these are just simulations, and they have to be tested rigorously. The team’s next step was to quantify these differences in the real world. The researchers explain that they “developed a technique focusing on local relationships between shoreline roughness and fetch area” to understand and quantify the differences. Specifically, they quantified what they call “roughness” to differentiate wave-driven erosion from uniform erosion. “Simply put, a lower roughness means a smoother stretch of shoreline compared to the rest of the lake, and a higher roughness means a comparatively rough stretch of shoreline,” they write.

This figure from the research shows roughness and fetch area for two of Titan’s seas: Kraken Mare and Ligeia Mare. C and D show roughness for each sea. E and F show the normalized fetch area, assuming waves are fetch-limited. Fetch-limited means waves continue to grow as long as the fetch length increases. G and H show normalized fetch area assuming a saturation fetch length of 20 km. That means that waves only grow up to a certain fetch length and then saturate. In that case, the system is saturation-limited, and the “fetch length in all directions is truncated to a maximum value.” Image Credit: Palermo et al. 2024.

The researchers say that “… shoreline roughness and normalized fetch area can be used to fingerprint wave-driven and uniform erosion and distinguish them from a coastline consisting only of flooded river valleys,” as shown in the first image.

So, what does this all boil down to?

“Our results suggest that the coastlines of Titan’s largest liquid bodies are most consistent with shorelines that have been modified by wave erosion and river incision,” the researchers write in their paper. They analyzed four coastlines and found a less than 5% probability of uniform erosion in a saturation-limited scenario and a less than 20% probability of uniform erosion in a fetch-limited scenario. That leaves wind-driven erosion as the most likely cause of erosion, which seems to confirm that Titan’s lakes and seas experience waves. “Therefore, our results suggest that the largest seas and lakes are not consistent with erosion by uniform processes (i.e., dissolution), as previously hypothesized for some of Titan’s landscapes,” they conclude.

That’s the scientific way of presenting their results, and their paper is like part of a long conversation with other scientists. In the press release, they state their conclusion more plainly for the rest of us.

“We can say, based on our results, that if the coastlines of Titan’s seas have eroded, waves are the most likely culprit,” said Perron, Professor of Earth, Atmospheric and Planetary Sciences at MIT. “If we could stand at the edge of one of Titan’s seas, we might see waves of liquid methane and ethane lapping on the shore and crashing on the coasts during storms. And they would be capable of eroding the material that the coast is made of.”

“Waves are ubiquitous on Earth’s oceans. If Titan has waves, they would likely dominate the surface of lakes,” says Juan Felipe Paniagua-Arroyave, associate professor in the School of Applied Sciences and Engineering at EAFIT University in Colombia, who was not involved in the study.” It would be fascinating to see how Titan’s winds create waves, not of water, but of exotic liquid hydrocarbons.”

The next step is to determine how strong Titan’s winds have to be to create coastal erosion. The researchers also hope to decipher which directions the wind is predominantly blowing from.

“Titan presents this case of a completely untouched system,” Palermo said. “It could help us learn more fundamental things about how coasts erode without the influence of people, and maybe that can help us better manage our coastlines on Earth in the future.”

The post Lake Shorelines on Titan are Shaped by Methane Waves appeared first on Universe Today.