Accumulated evidence does not demonstrate that elderberry has meaningful beneficial effects.
The post Elderberry (What is it good for) first appeared on Science-Based Medicine.We often talk about Jupiter’s Great Red Spot quite candidly but forget that hurricanes can be devastating, destructive forces here on Earth. Hurricane Milton is a reminder of the awful effects here on Earth. It came out of nowhere, appearing in the Gulf of Mexico as a tropical storm and two days later was a category 5 hurricane. It tracked a course and hit land near Siesta Key in Florida. NASA have been tracking the storm from space, recording high sea temperatures that fuelled the storm allowing it to grow. Images have been released from the ISS showing the sheer enormity of the hurricane.
Hurricanes form over warm oceans, typically in tropical regions of Earth. Their formation tends to start as a collection of thunderstorms over bodies of water where the temperature is at least 26.5 degrees celsius. The warm, moist air over the ocean rises creating a region of lower pressure at the surface.
Hurricanes Gordon and HeleneThe low pressure causes air to flow inward, warming and rising as it goes. It then cools and condenses to form clouds that release the heat. The heat then warms the surrounding air creating a continuous cycle of rising warm air and an inward movement of air. The system grows and eventually takes on a rotational movement due to the rotation of the Earth. When the winds are recorded to be sustained above 119 kilometres per hour, it is classed as a hurricane. They can continue to grow as long as their is a source of warm moist air so typically they hit landfall and start to weaken.
Watch this video of Hurricane Milton from the International Space Station
The inhabitants of Florida only just recovered from the effects of Hurricane Helene before warnings were received from another hurricane brewing over the Gulf of Mexico. Hurricane Milton started to form on 5 October and two days later had become a category 5 hurricane. Fuelling this leviathan of a hurricane are the higher than average sea temperatures in the Gulf of Mexico. Milton’s wind speeds rapidly increased from 28 to 281 kilometres per hour in 24 hours as the hurricane strengthened.
It wasn’t just warm oceans that intensified Milton so rapidly though, vertical wind shear was also a vital component. This change in winds with height interacts with the brewing thunderstorms to usually diminish a hurricanes ferocity. In the case of Milton, it was in a low-shear environment which means with changing altitude, there is usually very little difference in wind speed or direction. This allowed the storm to grown without being checked.
Thunderstorms over BrazilThe National Hurricane Centre (part of the National Oceanic and Atmospheric Administration) have been tracking Milton since its formation, paying particular attention to where it was likely to hit land and what path it was likely to follow. They were also able to determine (largely from imagery and data from orbiting infrastructure) that an eye-wall replacement cycle had completed. This process occurs when a new eye begins to develop around the old eye. The new eye slowly decreases in size and eventually replaces the old eye. Events such as these can cause the hurricane to grow but reduce wind speed. It can happen several times but then grow in intensity again if the conditions permit.
The eye of Hurricane Milton can be clearly seen in this image from the International Space Station
International Space Station. Credit: NASAWith astronauts on board the space station and the remote sensing technology available to them, NASA are a key part of disaster management teams. Their Disasters Response Coordination System has been used to support agencies dealing with the storm on the ground. They provide maps, images and data to help manage flooding, power outages and rain fall levels.
Our thoughts go out to all those effected by Hurricane Milton from all the team at Universe Today.
Source : Fuel for Hurricane Milton
The post NASA Reveals the Mind-Boggling Scale of Hurricane Milton seen from Space appeared first on Universe Today.
The total number of exoplanets discovered to date totals 5,288. Among them are a host of rocky, Earth-like exoplanets but none of them seem to have atmospheres. It’s a fairly challenging observation to make but a team of researchers think they’ve come up with a new, simpler technique. It involves measuring the combined temperature of a star and the exoplanet just before the planet passes behind. If it’s lower than expected, the planet is likely to have an atmosphere regulating its temperature!
The search for alien worlds has of course in itself an exciting journey. Finding other planets around distant stars helps us to understand more about possibility of life in the Universe. Finding other planets that could sustain life is perhaps one of the most exciting goals in modern science. Before we can get to that stage however, we need to first find worlds with atmospheres.
Coronagraph allowing the direct imaging of exoplanetsAtmospheres around Earth-like planets are key components for the development of life (I should add life like us since there could be a whole host of different biologies out there!) The layer of gas surrounding rocky worlds insulates the planet and acts to regulate its temperature to. Our own atmosphere warms during the day and cools at night but it redistributes the heat of the Sun around the planet keeping it a moderately temperate climate for life.
A view of Earth’s atmosphere from space. Credit: NASAA new study led by PhD student Qiao Xue from the University of Chicago has developed an intriguing new way to hunt for Earth-like planets with an atmosphere. Typically we we have relied upon the study of the light from the host star as the planet passes in front to reveal the presence of an atmosphere. It’s an approach which turns out to be far more efficient and simpler than previous methods.
The idea was first proposed in 2019 by Bean and Megan Mansfield to analyse the temperatures of the exoplanet and the star. More accurately the difference between the temperature of the exoplanet when at its hottest and the predicted temperature at its coldest. An atmosphere around an exoplanet would disperse the heat around the surface, reducing the day time temperature. The team theorised that if the actual temperature of an exoplanet is not as hot as it could be then an atmosphere must be present and redistributing the warmth. Until now thought, the technology was not sensitive enough. The James Webb Space telescope has changed that though.
Artist impression of the James Webb Space TelescopeAs an exoplanet passes in front of the host star, some of the star’s light is blocked and so the overall brightness decreases. As the planet passes almost behind the star then the light from the star and a little from the exoplanet allows for a measure of the brightness of the full system. As the planet passes behind then we can measure stellar brightness alone and, analysing the changes in light, the brightness and hence temperature of the planet can be deduced.
Using this technique, the team applied their attention to planet known as GJ1132 b 41 light years away. They concluded that it does not have an atmosphere because its measured temperature is too close to the calculated maximum temperature. It therefore cannot have an atmosphere redistributing the energy from its host star. It is therefore not a suitable candidate for live!
Source : UChicago researchers use new method of finding atmospheres in distant planets
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Mars has captured our imagination for centuries. Ever since the invention of the telescope our imagination has often drifted toward the possibility of life on Mars. Exploration of the red planet has often revealed that Mars once had plenty of water on its surface but it’s no longer there. Now NASA’s Curiosity rover has found deposits of carbon-rich minerals that could give us a much needed clue.
Mars Curiosity Rover was launched by NASA to the red planet in 2011. It’s part of the Mars Science Laboratory mission and, like many of the explorers, is a robotic mission. It arrived at Gale Crater on 6 August 2012 and was designed to explore the geological and climatic environments of Mars, search for signs that it was once a habitable world and to that end, was essentially a sampling and analysis mission. Originally it was a two year mission but Curiosity has continued long passed the intended duration, operating now for over a decade.
New simulations are helping inform the Curiosity rover’s ongoing sampling campaign. Credit:NASA/JPL-Caltech/MSSSMars, the fourth planet from the Sun, has been known to be a fairly hostile world devoid of any signs of life. Gale Crater was chosen as the target for Curiosity because it’s an impact crater formed just under 4 billion years ago. The layered rock formations found on the crater walls make it an ideal location to study the red planets geological history. The analysis is completed using the on board instruments SAM (Sample Analysis at Mars) and TLS (Tunable Laser Spectrometer) that heat up the samples to almost 900 degrees Celsius with the resultant gasses being analysed.
There’s methane on Mars, but only in Gale Crater, and only sporadically. Image Credit:As Curiosity explores Mars it has been measuring the isotopic composition (the ratios of different isotopes) of the minerals found in the crater. Isotopes are elements that have different masses than usual for example as water evaporates, lighter version of carbon and oxygen were likely to evaporate leaving heavier ones behind. Eventually, over time, the heavier versions (isotopes) became an integral part of the rocks that Curiosity is analysing. The minerals are largely carbon rich but they point toward high levels of evaporation suggesting they could only have formed when Mars could support liquid water.
David Burtt from NASA’s Goddard Space Flight Centre and lead author of the paper that describes the findings do not rule out ancient life either. He said “Our samples are not consistent with an ancient environment with life on the surface of Mars, although this does not rule out the possibility of an underground biosphere or a surface biosphere that began and ended before the carbonates formed.”
Their paper that was published in the National Academy of Sciences suggests there may have been two possible formation processes for the carbonates. A series of wet-dry cycles within the Gale Crater are one such possibility with the formation of carbonates in highly salty water under cold temperatures the other.
The two possible formation scenarios point to two different climate models and different habitability. The wet-dry cycling suggests an alternating climate between more and less habitable conditions. Alternatively the salty water process with cold temperatures would indicate a less habitable environment with most water locked up in ice and the rocks. Neither scenario is ideal for the establishment of complex life forms but as Burtt highlighted, it doesn’t rule out the possibility further back in the history of Mars.
Source : NASA: New Insights Into How Mars Became Uninhabitable
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