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Space travel comes with risk − and SpaceX’s Polaris Dawn mission will push the envelope further than any private mission has before

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theconversation.com – Chris Impey, University Distinguished Professor of Astronomy, University of Arizona – 2024-09-06 07:30:06

Spacewalks are among the more dangerous activities associated with human spaceflight.

Ignatiev/E+ via Getty Images

Chris Impey, University of Arizona

Space is an unnatural environment for humans. We can’t survive unprotected in a pure vacuum for more than two minutes. Getting to space involves being strapped to a barely contained chemical explosion.

Since 1961, fewer than 700 people have been into space. Private space companies such as SpaceX and Blue Origin hope to boost that number to many thousands, and SpaceX is already taking bookings for flights to Earth orbit.

I’m an astronomer who has written extensively about space travel, including a book about our future off-Earth. I think a lot about the risks and rewards of exploring space.

As the commercial space industry takes off, there will be accidents and people will die. Polaris Dawn, planned to launch early in September 2024, will be a high-risk mission using only civilian astronauts. So, now is a good time to assess the risks and rewards of leaving the Earth.

Space travel is dangerous

Most Americans vividly recall the disasters that led to the loss of 14 astronauts’ lives. Two of the five space shuttles disintegrated, Challenger in 1986 soon after launch and Columbia in 2003 on reentry.

The Challenger and Columbia accidents are two of the most prominent examples of the risk that comes with human spaceflight.

In total, 30 astronauts and cosmonauts have died while training for or during space missions.

There have also been dozens of close calls. Two astronauts are currently staying on the International Space Station for an extra six months because NASA declared their Boeing Starliner vehicle unsafe for the return journey. Starliner has had many problems during its development, including flammable tape, stuck valves and inadequate parachute systems. But a critical thruster malfunction is what caused NASA to abandon it as a return vehicle.

It’s not always safe on the ground, either. In addition to the three Apollo 1 astronauts who died in a 1967 launch pad fire, about 120 people died in the launchpad explosion of an unmanned rocket in Russia in 1960, and hundreds died in 1996 when a Chinese rocket veered off course and crashed into a nearby village.

The fatality rate of people traveling in space is about 3%. That sounds low, but it’s higher than extreme sports such as BASE jumping or jumping off a cliff wearing a wingsuit. The only recreations that rival the risk of space travel are solo free-climbing and climbing above 19,685 feet (6,000 meters) in the Himalayas.

Civilians in space

The 2020s have kicked off the era of civilian astronauts. After the death of schoolteacher Christa McAuliffe in the Challenger disaster, NASA stopped sending civilians into space. But for commercial space companies, it’s part of the business model.

The first all-civilian crew to reach orbit rode a SpaceX Dragon spacecraft in 2021, the Inspiration 4 mission. Since 2020, 69 private astronauts have gone to space, although only 46 reached the Kármán line – the formal definition of the edge of space.

The commercial space industry’s safety record is not perfect. No civilian has died in space, but one pilot died and another was seriously injured in a test flight of Virgin Galactic’s SpaceShipTwo craft in 2014. This accident followed three deaths and three injuries in an explosion during a prelaunch test of the SpaceShipTwo rocket in 2007.

SpaceX, the largest commercial space company with 13,000 employees and a market value of US$180 billion, has seen no fatalities in flight, but it has recorded one death and hundreds of injuries in the workplace.

The Polaris Dawn mission was planned to launch Aug. 27, 2024, though a helium leak and bad weather has delayed it. It will push the envelope of risk for civilians in space. This SpaceX flight will reach an altitude of 435 miles (700 kilometers), higher than any astronauts since Apollo.

Four astronauts wearing white suits and helmets stand in front of a rocket on a launchpad.

The Polaris Dawn crew during their launch-day rehearsal.

Polaris Program/John Kraus, CC BY-NC-ND

The Polaris Dawn’s four-person civilian crew will receive a hefty dose of radiation, getting as much in a few hours as they would in 20 years on the Earth. NASA is doing research to understand the extent of the health risks from radiation.

The mission will also include a spacewalk – the first for nongovernment astronauts. It will use spacesuits never tested in space. Since the spacecraft they’re using – the SpaceX Dragon – has no airlock, the inside of the capsule will be exposed to the vacuum of space, with all the crew members wearing spacesuits.

Russian cosmonaut Alexei Leonov nearly died during the first spacewalk in 1965, and other spacewalks have led to temporary blindness, near drowning and nearly being lost in space forever. A spacesuit is like a miniature spacecraft, and it has to withstand rapid temperature changes of hundreds of degrees when moving in and out of direct sunlight. Even a small tear or puncture can be fatal.

But while space travel comes with dangers, it also has rewards. Since Polaris Dawn will travel higher than any previous mission that did not go to the Moon, the crew will be able to do research on high-radiation environments. They will investigate the effects of spaceflight on the human body and evaluate how future deep-space travelers might diagnose and treat themselves.

A less tangible but potentially profound benefit is the overview effect – many astronauts report a feeling of awe from experiencing the Earth from space.

Space boom

Space is booming – hopefully just metaphorically and not literally. SpaceX makes money by launching Starlink satellites and ferrying supplies and people to the International Space Station, with estimated revenues of $15 billion this year. Blue Origin sells rocket engines and has contracts with NASA.

Both companies sell rides into space to high-net-worth individuals, but that’s a small fraction of their revenues. Space tourism is not available to the masses yet. Virgin Galactic offers a short, suborbital ride for $450,000, but getting to Earth orbit will cost you $55 million.

The space tourism market was $750 million in 2023, and that’s projected to grow to $5.2 billion over the next decade. Reusable rockets have made the cost of launching a spacecraft 10 times cheaper than it was a decade ago.

For space tourism to take off with a demographic broader than multimillionaires and thrill-seekers, it needs to be safe – both in perception and in reality. Many space entrepreneurs expect space travel to follow aviation’s arc, which also started by attracting rich people and thrill-seekers.

Since 1930, improvements in technology and safety features have lowered the number of fatal accidents in the aviation industry per million miles flown by a factor of 3,000. A more realistic target may be to make space travel as safe as driving. That’s a more lenient target, since driving is more dangerous than flying. Your annual odds of dying in a car crash are 1 in 5,000, compared with annual odds of 1 in 11 million of dying in a plane crash.

In the United States, the government has kept regulations light on the commercial space industry to encourage entrepreneurs.

Elon Musk’s dreams of millions of passengers and a city on Mars may not become reality. But if the cost of a jaunt to Earth’s orbit comes down to the cost of a high-end cruise, many people could experience the thrill of weightlessness and of seeing the Earth as a beautiful planet from above.The Conversation

Chris Impey, University Distinguished Professor of Astronomy, University of Arizona

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As Gaza ceasefire takes hold, Israeli forces turn to Jenin – a regular target seen as a center of Palestinian resistance

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theconversation.com – Maha Nassar, Associate Professor in the School of Middle Eastern and North African Studies, University of Arizona – 2025-01-22 17:42:00

Maha Nassar, University of Arizona

Just two days after a shaky ceasefire took hold in the Gaza Strip, Israel on Jan. 21, 2025, launched a large-scale incursion of the Jenin refugee camp in the West Bank.

Soldiers raided hundreds of homes in the West Bank city in what the Israeli military called a “counterterrorism” operation, aiming to reassert control there. Many analysts have suggested the raid is an attempt by Israeli Prime Minister Benjamin Netanyahu to appease far-right members of his coalition who oppose the ceasefire deal.

Whatever the motive, the offensive has been devastating for many of the camp’s residents. The Israeli military has destroyed infrastructure, closed entrances to local hospitals and forcibly displaced about 2,000 families, according to reports on the raids. As it was, life for inhabitants of the densely populated camp – home to some 24,000 Palestinian refugees – was hard. The West Bank director of UNRWA, the U.N. agency overseeing refugees, recently described camp conditions as “nearly uninhabitable.”

The focus of the latest Israeli operation is not new. The Jenin refugee camp, on the western edge of the town of Jenin in the north of the occupied West Bank, has often experienced violence between Israeli soldiers and Palestinian militants.

That violence has escalated since the Oct. 7, 2023, attacks, when Hamas gunmen led an incursion into Israel in which around 1,200 people were killed. The camp has faced repeated large-scale military operations by Israeli forces, including drone strikes, ground raids, and airstrikes that have caused widespread destruction. Meanwhile, Israeli settlers have torched Palestinian cars and properties, with 64 such attacks in the Jenin area alone since Oct. 7, 2023. Last December, the Palestinian Authority, which coordinates with Israel to oversee security in parts of the West Bank, also attacked local militants.

These events have deepened political tensions and worsened the economic and humanitarian crises in the West Bank. According to the U.N., more than a quarter of the 800-plus Palestinians killed in the West Bank since Oct. 7 attack have come from the Jenin district; several Israeli civilians have also been killed in the West Bank during the same period.

As a scholar of Palestinian history, I see this recent episode as the latest chapter in a much longer history of Palestinian displacement and defiance of Israeli occupation. Understanding this history helps explain why the Jenin camp in particular has become a target of Israeli offensives and a center of Palestinian militant resistance.

Camp conditions

Jenin, an agricultural town that dates back to ancient times, has long been a center of Palestinian resistance. During the 1948 Arab-Israeli War, Arab fighters successfully pushed back Israeli attempts to capture the town.

At the end of that war, the town became a refuge for some of the hundreds of thousands of Palestinian refugees who fled or were expelled from lands that became part of Israel. Jenin, along with the hilly interior of Palestine known as the West Bank, was annexed by Jordan.

The U.N. Relief and Works Agency established the Jenin camp in 1953, just west of the city. Since then, the agency has provided basic services to the camp’s residents, including food, housing and education.

Camp conditions have always been difficult. In the early years of the camp, refugees had to stand in long lines to receive food rations, and for decades their cramped homes lacked electricity or running water.

The Jenin camp soon became the poorest and most densely populated of the West Bank’s 19 refugee camps. And given its location near the “Green Line” – the armistice line that serves as Israel’s de facto border – camp residents who were expelled from northern Palestine could actually see the homes and villages from which they were expelled. But they were prevented from returning to them.

The rise of militancy

Since 1967, Jenin, along with the rest of the West Bank, has been occupied by the Israeli military.

The Israeli occupation of Jenin compounded the difficulties of these refugees. As stateless Palestinians, they couldn’t return home. But under Israeli occupation, they couldn’t live freely in Jenin, either. Human rights groups have long documented what has been described as “systematic oppression,” which includes discriminatory land seizures, forced evictions and travel restrictions.

Seeing no other path forward, many of the camp’s young refugees turned to armed resistance.

In the 1980s, groups such as the Black Panthers, which was affiliated with the Palestinian nationalist Fatah organization, launched attacks on Israeli targets in an effort to end the occupation and liberate their ancestral lands. Throughout the first intifada – a Palestinian uprising lasting from 1987 to 1993 – the Israeli army raided the Jenin camp many times, seeking to arrest members of militant groups. In the process, Israeli forces also sometimes demolished family members’ homes and arrested relatives. Such acts of apparent collective punishment reinforced the idea for many Palestinians that the Israeli occupation could only be ended by force.

A group of men in headscarves stand in front of flags and banners. One holds a pistol up in the air.
Members of the militant group Fatah in Jenin in 1991.
Esaias Baitel/Gamma-Rapho via Getty Images)

The Oslo peace process of the 1990s – which consisted of a series of meetings between Israeli government and Palestinian representatives – led some former militants to hope that the occupation could be ended through negotiations instead. But Jenin’s camp residents remained marginalized in the West Bank and sealed off from Israel, seeing little improvement in their lives, even after the transfer of administrative powers from Israel to the Palestinian Authority in 1995.

Independent projects like the The Freedom Theatre provided some relief to the camp’s refugee children, but it was not enough to overcome the grinding poverty or the violence they faced from Israeli soldiers and settlers. By the time the second intifada broke out in 2000, many of the camp’s teenagers joined militant groups. That included Freedom Theatre co-founder Zakaria Zubeidi, who joined the Fatah-affiliated Al-Aqsa Martyrs Brigade. Like the youth of the 1980s, they, too, concluded that only armed resistance would bring an end to the occupation.

A cycle of violence?

In April 2002, the Israeli army invaded the Jenin camp, hoping to put an end to such armed groups. There were fierce clashes between Israeli soldiers and young Palestinian men in the camp, solidifying Jenin’s reputation among Palestinians as “the capital of the resistance.”

The lack of progress on peace talks since then, Israel’s settlement building on occupied land – deemed illegal under international law – and the inclusion of hard-line Israeli politicians in the government have exacerbated resentment in the camp. Polls show Palestinians increasingly support armed resistance.

Seeking to protect the camp from Israeli incursions, in 2021 a group of local residents formed the Jenin Brigades. While its founder was affiliated with Palestinian Islamic Jihad, the group quickly drew in militants from various political factions. Members acquired weapons, patrolled the streets and fought off Israeli military incursions. By 2022, they had declared parts of the camp to be “liberated” from the Israeli occupation.

Seemingly alarmed by the increase in militancy and the stockpiling of weapons in the camp, Israel dramatically stepped up its raids in 2022. It was during such a raid that Palestinian American journalist Shireen Abu Akleh was killed by an Israeli soldier.

On July 3, 2023, the Israeli military again invaded Jenin, withdrawing after two days of heavy aerial bombardment and a ground invasion that killed 12 Palestinians and wounded over 100.

The latest offensive could well surpass that death toll, with at least 10 killed in the first day of fighting. But the militancy associated with the camp was built on decades of resistance and defiance to occupation that Israel has had little success in extinguishing. Similarly this time, I believe, such militancy within the camp will only increase with the latest deaths and destruction.

This article is an updated version of a story that was first published by The Conversation on July 5, 2023.The Conversation

Maha Nassar, Associate Professor in the School of Middle Eastern and North African Studies, University of Arizona

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What is seditious conspiracy, which is among the most serious crimes Trump pardoned?

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theconversation.com – Amy Cooter, Director of Research, Academic Development and Innovation at the Center on Terrorism, Extremism and Counterterrorism, Middlebury – 2025-01-22 15:12:00

The Jan. 6, 2021, storming of the Capitol was the result of a planned conspiracy to disrupt the government, prosecutors alleged.
AP Photo/John Minchillo

Amy Cooter, Middlebury

Several of the highest-profile figures in the Jan. 6, 2021, insurrection were charged with, and convicted of, the crime of seditious conspiracy, which is defined as the act of getting together with other people to overthrow the government. They were among the roughly 1,500 people involved in the insurrection who were pardoned or had their prison sentences commuted by Donald Trump on his first day in office.

Seditious conspiracy is a serious crime of conspiring to overthrow the government or stop its normal functioning. Historically, seditious conspiracy has been difficult to successfully prosecute.

In 2009, for example, a state judge ruled that prosecutors had failed to provide sufficient evidence for members of the Michigan Hutaree militia to go to trial on that charge. Certain militia members had been accused of plotting violence against police officers. While some members faced other charges for their actions, the judge determined that a plot against law enforcement was not sufficient to support charges of attempting to overthrow the government.

In contrast, the U.S. Department of Justice charged 18 people associated with the Jan. 6 attack on the U.S. Capitol with that crime, asserting that they had intended to “oppose by force the lawful transfer of presidential power” or had committed other actions that would undermine the entire system of government.

Of those 18, four pleaded guilty, and 10 were found guilty at trial. The remaining four were found not guilty of seditious conspiracy but were convicted of other crimes that were related to the insurrection.

Capitol entry not required

Oath Keepers militia leader Stewart Rhodes’ seditious conspiracy conviction was especially significant because, unlike some other defendants, Rhodes did not physically enter the Capitol building. He was instead in “the restricted area of Capitol grounds,” according to a Justice Department statement.

His conviction was based in part on his communications, including text messages, both before Jan. 6 and on the day itself. Prosecutors successfully argued that these communications were part of a broader conspiracy to disrupt the election certification by organizing and encouraging others to participate in more direct action.

Two men walk in front of a group of masked men with the Washington Monument in the background.
Proud Boys members Joseph Biggs, left, and Ethan Nordean, right with megaphone, walk toward the U.S. Capitol in Washington, D.C., on Jan. 6, 2021.
AP Photo/Carolyn Kaster

Militias respond to convictions – and clemency

Many observers believed successful prosecutions for these charges sent a strong message that violence against a democratically elected government was not acceptable.

Scholars of militia activity like me saw a period of relative quiet through much of Joe Biden’s presidency, which was, in part, likely due to the consequences the Jan. 6 defendants faced.

Some groups, however, continued social media discussions of their beliefs that the 2020 election had been “stolen,” as Trump continues to falsely claim, and which was used as justification by militia members for their attack. Trump himself said publicly he thought the defendants were unjustly persecuted and promised to pardon them if and when he returned to power.

The full effect that the pardons will have on militia actors and related groups in coming years is uncertain: Will the pardons send the message to all Americans that political violence is acceptable, or at least that it can be overlooked or forgiven if the right political figures are in power?The Conversation

Amy Cooter, Director of Research, Academic Development and Innovation at the Center on Terrorism, Extremism and Counterterrorism, Middlebury

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Ozempic and similar weight loss drugs may lower risk of 42 health conditions, but also pose risks

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theconversation.com – Ziyad Al-Aly, Clinical Epidemiologist, Washington University in St. Louis – 2025-01-22 14:11:00

The research shows the health effects of these drugs are significant and wide-ranging.
Mario Tama via Getty Images News

Ziyad Al-Aly, Washington University in St. Louis

Several years ago, a little-known drug named Ozempic – previously used only to treat diabetes – emerged as a promising new drug for weight management.

The Food and Drug Administration’s approval of Ozempic in 2021 for weight loss treatment ushered in a new era for the class of drugs called glucagon-like peptide-1 agonists, or GLP-1.

Today, GLP-1 drugs, including Wegovy, Mounjaro and Zepbound, have become household names and key tools in the fight against obesity: 1 in 8 American adults say they have used a GLP-1 drug, and forecasts show that by 2030, 1 in 10 Americans will likely be using these medications.

Now, research from my lab and others suggests that GLP-1 drugs could help treat dozens of other ailments as well, including cognitive issues and addiction problems. However, my colleagues and I also found previously unidentified risks.

I am a physician-scientist and I direct a clinical epidemiology center focused on addressing public health’s most urgent questions. My team works to address critical knowledge gaps about COVID-19, long COVID, influenza, vaccines, effectiveness and risks of commonly used drugs, and more.

On Jan. 20, 2025, my team published a study of more than 2.4 million people that evaluated the risks and benefits of GLP-1 drugs across 175 possible health outcomes. We found that these drugs lowered risks of 42 health outcomes, nearly a quarter of the total that we analyzed. These include neurocognitive disorders such as Alzheimer’s disease and dementia, substance use and addiction disorders, clotting disorders and several other conditions.

Unfortunately, we also found that GLP-1 drugs come with significant side effects and increase the risk of 19 health conditions we studied, such as gastrointestinal issues, kidney stones and acute pancreatitis, in which the pancreas becomes inflamed and dysfunctional.

Initially, GLP-1 drugs were developed to treat diabetes.

Cognitive benefits

One of the most important health benefits we found was that the GLP-1 drugs lowered the risk of neurodegenerative disorders, including Alzheimer’s disease and dementia. These findings align with other research, including evidence from preclinical studies showing that these drugs may reduce inflammation in the brain and enhance the brain’s ability to form and strengthen connections between its cells, improving how they communicate with one another. These effects contribute to mitigating cognitive decline.

Two other key studies have shown that patients treated with a GLP-1 drug for diabetes had a lower risk of dementia.

All of these studies strongly point to a potential therapeutic use of GLP-1 drugs in treatment of the cognitive decline. Ongoing randomized trials – the gold standard for evaluating new uses of drugs – are looking at the effects of GLP-1 drugs in early Alzheimer’s disease, with results expected later in 2025.

Curbing addiction and suicidal ideation

GLP-1 drugs have also demonstrated potential in reducing risks of several substance use disorders such as those involving alcohol, tobacco, cannabis, opioids and stimulants. This may be due to the ability of these drugs to modulate reward pathways, impulse control and inflammatory processes in the brain.

The effectiveness of GLP-1 drugs in curbing addictive behavior may explain their spectacular success in treating obesity, a chronic disease state that many have suggested is indeed a food addiction disorder.

Our study demonstrated a reduced risk of suicidal thoughts and self-harm among people using GLP-1 drugs. This finding is particularly significant given earlier reports of suicidal thoughts and self-injury in people using GLP-1 drugs. In response to those reports, the European Medicines Agency conducted a review of all available data and concluded that there was no evidence of increased risk of suicidality in people using GLP-1 drugs.

Now at least two studies, including our own, show that GLP-1 drugs actually reduce the risk of suicidality.

Other benefits

In addition to the well-documented effects of GLP-1 drugs in reducing risks of adverse cardiovascular and kidney outcomes, our study shows a significant effect in reducing risk of blood clotting as well as deep vein thrombosis and pulmonary embolism.

One puzzling finding in our study is the reduced risk of infectious diseases such as pneumonia and sepsis. Our data complements another recent study that came to a similar conclusion showing that GLP-1 drugs reduced risk of cardiovascular death and death due to infectious causes, primarily COVID-19.

This is especially important since COVID-19 is regarded as a significant cardiovascular risk factor. Whether GLP-1 drugs completely offset the increased risk of cardiovascular disease associated with COVID-19 needs to be thoroughly evaluated.

GLP-1 drugs may also be useful in treating fatty liver disease and conditions ranging from asthma to chronic obstructive pulmonary disease, sleep apnea, osteoarthritis, depression and eye disorders.

Some doctors are prescribing GLP-1 drugs to help with fertility issues.

Risks and challenges

Despite their broad therapeutic potential, GLP-1 drugs are not without risks.

Gastrointestinal issues, such as nausea, vomiting, constipation and gastroesophageal reflux disease are among the most common adverse effects associated with GLP-1 drugs.

Our study also identified other risks, including low blood pressure, sleep problems, headaches, formation of kidney stones, and gall bladder disease and diseases associated with the bile ducts. We also saw increased risks of drug-induced inflammation of the kidneys and pancreas – both serious conditions that can result in long-term health problems. These findings underscore the importance of careful monitoring in people who are taking GLP-1 medications.

A significant challenge with using GLP-1 drugs is the high rates at which patients stop using them, often driven by their exorbitant cost or the emergence of adverse effects. Discontinuation can lead to rapid weight gain.

That’s a problem, because obesity is a chronic disease. GLP-1 drugs provide effective treatment but do not address the underlying causes of obesity and metabolic dysfunction. As a result, GLP-1 drugs need to be taken long term to sustain their effectiveness and prevent rebound weight gain.

In addition, many questions remain about the long-term effectiveness and risks of these drugs as well as whether there are differences between GLP-1 formulations. Addressing these questions is critical to guide clinical practice.The Conversation

Ziyad Al-Aly, Clinical Epidemiologist, Washington University in St. Louis

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