Astronauts aboard the International Space Station (ISS) follow a rigorous exercise routine to counteract the lack of gravity, which affects muscles and bones. While missions usually last six months, some astronauts stay up to a year. Researchers are confident in maintaining astronaut health over this duration.

On Earth, even basic movement builds muscle and strengthens bones due to gravitational resistance. However, in orbit, astronauts rely on three exercise machines, including a resistance device installed in 2009. This device simulates free weights using vacuum tubes and flywheel cables.

A two-hour daily workout routine is essential for astronaut fitness. “The best results that we have to show that we’re being very effective is that we don’t really have a fracture problem in astronauts when they return to the ground,” said Bokhari. However, bone loss remains detectable in scans.

Balance and fluid shifts pose major concerns

Space travel disrupts balance, affecting all astronauts, even those on short missions. Emmanuel Urquieta, vice chair of Aerospace Medicine at the University of Central Florida, stated that astronauts must undergo NASA’s 45-day post-mission rehabilitation program to retrain their bodies.

Another issue is “fluid shift,” where bodily fluids move toward the head in microgravity. This can increase calcium levels in urine, raising the risk of kidney stones. Additionally, fluid shifts can lead to increased intracranial pressure, altering the shape of the eyeball and causing spaceflight-associated neuro-ocular syndrome (SANS), resulting in mild-to-moderate vision impairment.

Interestingly, in some cases, SANS has led to improved vision. NASA astronaut Jessica Meir, for instance, experienced a rare benefit. “When I launched, I wore glasses and contacts, but due to globe flattening, I now have 20/15 vision—most expensive corrective surgery possible. Thank you, taxpayers,” she remarked.

Managing radiation risks

Radiation exposure remains a significant concern. While the ISS passes through the Van Allen radiation belt, Earth’s magnetic field offers some protection. However, radiation levels remain higher than on Earth. NASA aims to limit astronauts’ increased lifetime cancer risk to within three percent.

Future deep-space missions to the Moon and Mars will expose astronauts to even greater radiation levels. Astrophysicist Siegfried Eggl explained that while heavy materials like lead or water provide effective shielding, their vast quantity requirements make them impractical.

Space probes could offer some warning for coronal mass ejections—plasma clouds from the Sun—but cosmic radiation remains largely unpredictable.

Possible solutions: Artificial gravity and propulsion advancements

One solution to counteract health issues is artificial gravity, created by rotating spacecraft frames, which could help astronauts remain functional after extended travel. Another approach is using powerful acceleration and deceleration to simulate Earth’s gravity, reducing both the effects of microgravity and radiation exposure. However, this method requires nuclear propulsion technologies that are still under development.

Psychological challenges in space missions

Beyond physical health, maintaining team dynamics in confined environments is crucial. Joseph Keebler, a psychologist at Embry-Riddle Aeronautical University, highlighted the difficulty of long-duration space travel.

“Imagine being stuck in a van with anybody for three years: these vessels aren’t that big, there’s no privacy, there’s no backyard to go to,” he explained. “I really commend astronauts that commit to this. It’s an unfathomable job.”

Astronaut Sunita Williams and Butch Wilmore are finally on their way back to Earth after spending over nine months in space. NASA confirmed that the spacecraft carrying them successfully undocked from the International Space Station (ISS), marking the beginning of their return journey.

The Crew Dragon spacecraft, launched by SpaceX atop a Falcon 9 rocket, detached from the ISS at 10:35 AM (IST). NASA also shared a video of the moment, showcasing the long-awaited departure.

Nine-month delay after Boeing Starliner failure

Sunita Williams and Butch Wilmore initially traveled to the ISS on June 5 last year aboard Boeing’s Starliner for what was supposed to be an eight-day mission. However, technical issues with the Starliner’s propulsion system left them stranded in space. The capsule was deemed unfit to bring them back and was returned to Earth without a crew in September.

With uncertainty looming over their return, NASA reassigned them to SpaceX’s Crew-9 mission. Unlike the usual four-member crew, SpaceX sent a Dragon spacecraft with only two astronauts to the ISS in September, ensuring the stranded crew could return.

Four astronauts onboard return mission

After multiple delays, the SpaceX Dragon spacecraft successfully docked at the ISS on Sunday. Now, with the undocking complete, the crew has begun their 17-hour journey back to Earth.

The return flight includes four astronauts: Sunita Williams, Butch Wilmore, NASA’s Nick Hague, and Roscosmos cosmonaut Aleksandr Gorbunov. Their spacecraft is expected to splash down off the Florida coast at approximately 3:27 AM (IST) on Wednesday.

An indigenously developed gene therapy for specific blood cancers has demonstrated a 73% response rate in clinical trials, offering new hope for patients in India. The findings, published in The Lancet Haematology, highlight the success of CAR T-cell therapy, which modifies a patient’s immune cells to combat cancer.

A breakthrough in cancer treatment

The therapy was developed through a collaboration between the Indian Institute of Technology-Bombay (IIT-B) and Tata Memorial Hospital, Mumbai. It has been designed to treat patients with relapsed or refractory B-cell malignancies, including leukemia and lymphoma, which often have poor outcomes due to limited treatment options.

Speaking on the impact of this therapy, Rahul Purwar, lead author and IIT-B professor, stated,

“The clinical trials of India’s first gene therapy for cancer offer hopes of another chance to live among these patients, that there is one more drug that doctors can try.”

Affordable alternative to global therapies

Unlike CAR T-cell therapies in developed nations, which cost between $373,000 to $475,000, the India-made injection ‘talicabtagene autoleucel’ is available for $30,000—making it significantly more affordable.

Developed over 11 years, the therapy was tested in two trial phases:

• Phase 1: Included 14 patients (18+ years) with B-cell lymphoma.
• Phase 2: Expanded to 50 patients (15+ years) with B-cell leukemia or lymphoma.

Among the 51 patients analyzed, the overall response rate was 73%, with two treatment-related deaths. Common side effects included neutropenia (low white blood cell count), thrombocytopenia (low platelet count), and anemia.

Future scope and clinical advancements

Dr. Hasmukh Jain, a medical oncology professor at Tata Memorial Hospital, emphasized the long-term benefits of CAR T-cells in preventing cancer relapse. He noted that new trials are underway to test the therapy in earlier settings and in combination with other immunotherapies at Tata Memorial Centre.