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NASA boosts impact risk from 'potentially hazardous' asteroid Bennu – Yahoo Movies Canada

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NASA boosts impact risk from ‘potentially hazardous’ asteroid Bennu

Potentially hazardous asteroid Bennu just became slightly more potentially dangerous.

Over a century from now, in 2135, a half-kilometre-wide asteroid named 101955 Bennu will pass between the Earth and the Moon. While there is absolutely no chance of an impact with Bennu at that time, the close encounter throws uncertainty into the predictions. As a result, there’s no saying for sure that Earth will be safe from Bennu afterward.

Before NASA sent their OSIRIS-REx spacecraft to Bennu, astronomers tracked asteroid Bennu using telescopes. Their observations gave us very accurate calculations of Bennu’s orbit. The relatively close passes of Bennu in 1999, 2005 and 2011 helped with this. Although it was officially classified as a “Potentially Hazardous Asteroid” (PHA), NASA could rule out any possibility of a Bennu impact for the next 100+ years.

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However, the September 2135 encounter added an extra complication. The asteroid comes very close to Earth at that time. On September 24 of that year, its absolute minimum distance could be around 110,000 km from the planet’s surface or less than one-third the distance to the Moon. As it flies past, it will encounter one of several ‘gravitational keyholes’. As it passes through one of these tiny points in space, Earth’s gravity will tug on the asteroid and alter its orbit around the Sun.

Bennu Sept 2135 keyholes - NASA/GoddardBennu Sept 2135 keyholes - NASA/Goddard

Bennu Sept 2135 keyholes – NASA/Goddard

This screenshot of an animation used during the NASA press briefing on Wednesday, August 11, 2021, shows the potential paths of Bennu during the 2135 flyby, based on the most up-to-date telescope observations, with a separate ‘gravitational keyhole’ for each path. Credit: NASA/Goddard

Even with the carefully plotted orbit of Bennu, the minor uncertainties made it challenging to tell which ‘keyhole’ it would pass through during that 2135 flyby. Thus, there was no way to know with any certainty which orbit it would end up on afterward.

This was of great concern to scientists because it introduced over 150 possible impacts, with a cumulative 1 in 2,700 impact chance between 2135 and 2300. The most likely impact would be on September 24, 2182.

Bennu Sept 2182 potential impact - NASA/GoddardBennu Sept 2182 potential impact - NASA/Goddard

Bennu Sept 2182 potential impact – NASA/Goddard

The effects of one particular ‘gravitational keyhole’ could have disastrous results in 2182. Credit: NASA/Goddard

With OSIRIS-REx following along with the asteroid for over two years, though, it gave scientists an unprecedented chance to closely track the influence of the Yarkovsky effect.

The Yarkovsky effect is a tiny, constant ‘push’ that an asteroid receives as it radiates heat into space.

Watch below: How the Sun pushes asteroids around the solar system

Click here to view the video

According to Davide Farnocchia from the Center for Near Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Lab, who is the lead author of a new study published this week, the force of this ‘push’ on Bennu is equivalent to about the weight of three grapes.

“Think about that, just three grapes,” Farnocchia said in a NASA teleconference on Wednesday. “Because this acceleration is persistent, its effect builds up over time, and it becomes very significant by the time we get to 2135.”

“The OSIRIS-REx data give us so much more precise information, we can test the limits of our models and calculate the future trajectory of Bennu to a very high degree of certainty through 2135,” Farnocchia said in a NASA press release. “We’ve never modelled an asteroid’s trajectory to this precision before.”

Based on their study of the Yarkovsky effect on Bennu, Farnocchia and his colleagues calculated an updated cumulative probability of a Bennu impact between 2135 and 2200. Instead of 1 in 2,700, the chance is now just 1 in 1,750. The individual chance of an impact on September 24, 2182, is now 1 in 2,700.

It should be noted that these probabilities are tiny.

A 1 in 1,750 chance is equal to a 0.057 per cent impact probability, while 1 in 2,700 is equivalent to 0.037 per cent. That means there’s over a 99.94 per cent chance that Bennu will miss Earth on all the potential encounters it has towards the end of the 22nd century. Specifically for September 2182, there’s a 99.96 per cent chance of a miss.

During their research, Farnocchia and the others accounted for every conceivable force that could affect Bennu’s orbit. They even considered whether the Touch-and-Go (TAG) maneuver that netted NASA a sample of the asteroid was enough to alter its trajectory.

Watch below: NASA’s OSIRIS-REx tags asteroid Bennu

Click here to view the video

“The force exerted on Bennu’s surface during the TAG event were tiny even in comparison to the effects of other small forces considered,” Rich Burns, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center, said in the press release. “TAG did not alter Bennu’s likelihood of impacting Earth.”

The next steps in determining Bennu’s true potential as a threat to Earth will come in 2023 and 2037.

In 2023, OSIRIS-REx will swing past Earth. On its way past, it will drop off the sample it collected from Bennu’s surface back in the Fall of 2020. As scientists examine these samples in the laboratory, we will learn more about Bennu’s composition. This might provide information about how we could deflect such an asteroid on an impact trajectory.

In 2037, Bennu will be making its next close (but safe) flyby past Earth. During this pass, radio telescopes can gather radar data on the asteroid. These readings will help confirm the calculations made based on OSIRIS-REx’s data and give us an even better estimate of its exact path for that 2135 encounter.

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Ancient plankton migration offers clues to future marine extinctions – Open Access Government

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image: @CHUNYIP WONG | iStock

Researchers reveal new insights into how marine communities responded to extreme global warming events millions of years ago and how that informs our research today

The research teams from the University of Bristol, Harvard University, the University of Texas Institute for Geophysics, and the University of Victoria look at the potential impact of current and future climate change on marine ecosystems.  

Past climate events 

The research focused on the Early Eocene Climatic Optimum, a period about 66 million years ago known for its exceptionally high global temperatures, similar to the most severe global warming scenarios predicted today. 

During this time, marine organisms, particularly plankton, faced unusual heat stress. The findings suggest that most marine communities, except for highly specialised species, migrated towards cooler regions to escape the tropical heat.

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Dr Adam Woodhouse from the University of Bristol’s School of Earth Sciences, who led the study, explained the significance of these discoveries: “We knew that biodiversity amongst marine plankton groups has changed throughout the last 66 million years, but no one had ever explored it on a global, spatial, scale through the lens of a single database.”

Using the past to predict the future 

The team used the Triton dataset developed by Dr. Woodhouse during his PhD to analyse global biodiversity changes over millions of years. By applying innovative network analysis techniques to micropalaeontology, they reconstructed global spatial changes in marine community structures across the Cenozoic era.

“The fossil record of marine plankton is the most complete and extensive archive of ancient biological changes available to science,” noted Dr. Woodhouse. “By applying advanced computational analyses to this archive we were able to detail the global community structure of the oceans since the death of the dinosaurs, revealing that community change often precedes the extinction of organisms.”

This study will hold importance for modern marine ecosystems; it is important to continue monitoring and researching. By using the new data, it will be easier to predict the impacts of climate change on marine biodiversity. 

By expanding the research to other marine groups and incorporating new models, the team aims to use historical patterns to predict future changes in marine community structures under different warming scenarios. 

Understanding how marine communities responded to ancient climate extremes provides insights into the resilience and vulnerability of modern ecosystems. 

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April 20: Why this Indigenous researcher thinks we can do science differently and more… – CBC.ca

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Quirks and Quarks54:00Why this Indigenous researcher thinks we can do science differently, and more…


On this episode of Quirks & Quarks with Bob McDonald:

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This researcher wants a new particle accelerator to use before she’s dead

Quirks and Quarks9:05This researcher wants a new particle accelerator to use before she’s dead

Physicists exploring the nature of reality need ever more capable particle colliders, so they’re exploring a successor to the Large Hadron Collider in Europe. But that new machine is at least decades away. Tova Holmes, an assistant professor at the University of Tennessee, Knoxville, is one of the physicists calling for a different kind of collider that can come online before the end of her career – or her life. This device would use a particle not typically used in particle accelerators: the muon.

A 2021 CERN file photo of the Large Hadron Collider inside the 27-kilometre tunnel near Geneva, Switzerland. The proposed new particle accelerator would require an even larger tunnel, one that’s over 100 kilometres. Physicists calling for the development of a muon accelerator say it will require much less space. (Samuel Joseph Hertzog/CERN)

Is venting the best way to deal with anger? The scientist says chill out.

Quirks and Quarks6:51Is venting the best way to deal with anger? The scientist says chill out

It turns out that acting out your anger might not be the best way to get rid of it. Sophie Kjaervik, a researcher at Virginia Commonwealth University in Richmond, Va., analyzed 154 studies of the different ways to deal with anger. Her results, published in the journal Clinical Psychology Review, suggest that techniques that reduce your heart rate and calm your mind are more effective than blowing off steam.


High intensity wildfires may release toxic forms of metals

Quirks and Quarks8:37High intensity wildfires may release toxic forms of metals

Wildfire smoke might be more dangerous than you think. A recent study in the journal Nature Communications found that when wildfires pass over soils or rocks rich in a normally harmless metal called chromium, it is transformed into a toxic form. The hotter and more intense the wildfire is, the more of this metal becomes toxic. Scott Fendorf, an Earth system science professor at Stanford University, said this study shows we should factor in the type of geology wildfires pass over to provide more targeted air quality warnings about smoke risks. 

A man sitting on a balcony with the backdrop of Montreal's skyline behind him is talking on the phone while wearing two masks: one surgical one still on his face and a black one that in this photo is pulled down below his chin.
A man wears a face mask as he cycles by the skyline of Montreal, Sunday, June 25, 2023. A smog warning is in effect for Montreal and multiple regions of the province due to forest fires. (Graham Hughes/The Canadian Press)

AI might help solve the problem of runaway conspiracy theories

Quirks and Quarks7:35AI might help solve the problem of runaway conspiracy theories

Conspiracy theories seem to have multiplied in the internet era and so far, we haven’t had much luck in debunking these beliefs. The preliminary findings of a new study on PsyArXiv, a site for psychology studies that have yet to be peer-reviewed, suggests that artificial intelligence may have more success. Thomas Costello, a postdoctoral psychology researcher at MIT was the lead author on this study, and said their findings can provide a window into how to better debunk conspiracy beliefs. 

One eye takes up the entire frame and directly in the centre of their pupil, you see the reflection of the ChatGPT logo.
This illustration photograph taken with a macro lens shows The OpenAI company logo reflected in a human eye at a studio in Paris on June 6, 2023. ChatGPT is a conversational artificial intelligence software application developed by OpenAI. (Joel Saget/AFP/Getty Images)

An Indigenous scientist explores the medicine the Earth needs

Quirks and Quarks19:12An Indigenous ecologist on why we need to stop and listen to save the planet

Earth day is April 22. And Earth is not in great shape to celebrate the day. Overheated, overpopulated, overexploited – we’re not being particularly careful with our planet. We talk to Indigenous ecologist Jennifer Grenz of the University of British Columbia about her new book, which is part memoir, part prescription for the medicine our planet needs – a compound of science and traditional wisdom.  Her book is Medicine Wheel for the Planet: A journey toward personal and ecological healing.

READ MORE: An Indigenous ecologist on why we need to stop and listen to save the planet

A shot of a woman wearing big green glasses outside, looking at a tree branch.
Jennifer Grenz is an Indigenous Ecologist and author of Medicine Wheel for the Planet: A journey toward personal and ecological healing. (Paulo Ramos/UBC)

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Dragonfly: NASA greenlights most important mission of the century – Earth.com

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In a remarkable development, NASA has given the green light to the Dragonfly mission, a revolutionary rotorcraft designed to investigate the complex chemistry of Saturn‘s moon Titan.

This confirmation allows the mission to proceed with the final design, construction, and testing of the spacecraft and its scientific instruments.

Deciphering the prebiotic chemistry on Titan

The Dragonfly mission, led by Dr. Melissa Trainer of NASA’s Goddard Space Flight Center, will carry a cutting-edge instrument called the Dragonfly Mass Spectrometer (DraMS).

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This powerful tool will help scientists delve into the intricate chemistry at work on Titan, potentially shedding light on the chemical processes that led to the emergence of life on Earth, known as prebiotic chemistry.

“We want to know if the type of chemistry that could be important for early pre-biochemical systems on Earth is taking place on Titan,” explains Dr. Trainer, a planetary scientist and astrobiologist specializing in Titan.

Titan: Dragonfly’s target

Titan, the largest moon of Saturn, is shrouded in a dense nitrogen-rich atmosphere, bears a striking resemblance to Earth in many ways. With a diameter of 5,150 kilometers, Titan is the second-largest moon in our solar system, surpassed only by Jupiter’s Ganymede.

Dense atmosphere and unique climate

One of Titan’s most distinctive features is its thick atmosphere, which is composed primarily of nitrogen and methane. This dense atmosphere creates a surface pressure 1.5 times higher than Earth’s, making it the only moon in our solar system with a substantial atmosphere.

The presence of methane in Titan’s atmosphere leads to a fascinating hydrological cycle, similar to Earth’s water cycle, but with methane as the primary liquid.

Titan’s surface is dotted with numerous lakes and seas of liquid hydrocarbons, predominantly methane and ethane. These liquid bodies, some of which are larger than the Great Lakes on Earth, are the result of Titan’s unique climate and atmospheric conditions.

The Cassini mission, which explored the Saturn system from 2004 to 2017, provided stunning images and data of these extraterrestrial lakes and seas.

Dragonfly mission to search Titan for prebiotic chemistry and life

The complex chemistry occurring on Titan’s surface and in its atmosphere has drawn significant attention from astrobiologists.

With its abundant organic compounds and the presence of liquid methane, Titan is considered a prime candidate for studying prebiotic chemistry and the potential for life to emerge in environments different from Earth.

Beneath Titan’s icy crust lies another intriguing feature: a global subsurface ocean of liquid water and ammonia. This ocean, which is believed to be salty and have a high pH, may potentially host microbial life.

The presence of this subsurface ocean, along with the unique chemistry on Titan’s surface, makes this moon a fascinating target for future exploration and scientific research.

Pushing the boundaries of rotorcraft exploration

Nicky Fox, associate administrator of the Science Mission Directorate at NASA Headquarters, emphasized the significance of the Dragonfly mission, stating, “Exploring Titan will push the boundaries of what we can do with rotorcraft outside of Earth.”

Titan’s unique characteristics, including its abundant complex carbon-rich chemistry, interior ocean, and past presence of liquid water on the surface, make it an ideal destination for studying prebiotic chemical processes and the potential habitability of an extraterrestrial environment.

Innovative design and cutting-edge technology

The Dragonfly robotic rotorcraft will leverage Titan’s low gravity and dense atmosphere to fly between different points of interest on the moon’s surface, spanning several miles apart.

This innovative approach allows the entire suite of instruments to be relocated to new sites once the previous one has been thoroughly explored, providing access to samples from diverse geological environments.

DraMS, developed by the same team responsible for the Sample Analysis at Mars (SAM) instrument suite aboard the Curiosity rover, will analyze surface samples using techniques tested on Mars.

Dr. Trainer emphasized the benefits of this heritage, stating, “This design has given us an instrument that’s very flexible, that can adapt to the different types of surface samples.”

Dragonfly mission challenges and funding

The Dragonfly mission successfully passed its Preliminary Design Review in early 2023. However, due to funding constraints, the mission was asked to develop an updated budget and schedule.

The revised plan, presented and conditionally approved in November 2023, hinged on the outcome of the fiscal year 2025 budget process.

With the release of the president’s fiscal year 2025 budget request, Dragonfly is now confirmed with a total lifecycle cost of $3.35 billion and a launch date set for July 2028.

This reflects a cost increase of approximately two times the initially proposed cost and a delay of more than two years from the original selection in 2019.

Despite the challenges posed by funding constraints, the COVID-19 pandemic, supply chain issues, and an in-depth design iteration, NASA remains committed to the Dragonfly mission.

Additional funding has been provided for a heavy-lift launch vehicle to shorten the mission’s cruise phase and compensate for the delayed arrival at Titan.

Rigorous testing and validation

To ensure the success of the Dragonfly mission, researchers on Earth have conducted extensive testing and validation of the designs and models for the nuclear-powered, car-sized drone.

The mission team has carried out test campaigns at NASA’s Langley Research Center, utilizing the Subsonic Tunnel and the Transonic Dynamics Tunnel (TDT) to validate computational fluid dynamics models and gather data under simulated Titan atmospheric conditions.

Ken Hibbard, Dragonfly mission systems engineer at APL, emphasized the importance of these tests, stating, “All of these tests feed into our Dragonfly Titan simulations and performance predictions.”

As the Dragonfly mission progresses, it marks a new era of exploration and scientific discovery. Dr. Trainer expressed her excitement, saying, “Dragonfly is a spectacular science mission with broad community interest, and we are excited to take the next steps on this mission.”

Turning science fiction into fact with the Dragonfly mission

In summary, the Dragonfly mission embodies the essence of human curiosity and the relentless pursuit of knowledge. As NASA prepares to send this revolutionary rotorcraft to the alien world of Titan, we stand on the brink of a new era of exploration and discovery.

With its innovative design, cutting-edge technology, and the unwavering dedication of the mission team, Dragonfly will unlock the secrets of prebiotic chemistry and shed light on the potential for life beyond Earth.

As we eagerly await the launch of this titanic mission, we can only imagine the wonders that await us on Saturn’s enigmatic moon. The Dragonfly mission is a testament to the indomitable human spirit and our boundless capacity to push the frontiers of knowledge.

In the words of Ken Hibbard, “With Dragonfly, we’re turning science fiction into exploration fact,” and that fact will undoubtedly inspire generations to come.

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