Humans are explorers. Since before the dawn of civilization, we’ve been lured over the horizon to find food or more space, to make a profit, or just to see what’s beyond those trees or mountains or oceans.

Despite decades of scientific and technological achievements,

We’ve successfully put laboratories onto the surface

Astronauts are far from the shops, so they have to rely on regular deliveries of food. Every few months an automated spacecraft, such as ESA’s Automated Transfer Vehicle or the Russian Progress, arrives loaded with fresh fruit, water and pre-packed meals.

Some recycled water is produced on the Station, but extra supplies have to be sent up on resupply missions. Drinks range from coffee, tea and orange juice to fruit punches and lemonade.

Eating in space has improved a lot since the days of cold paste in aluminium tubes and cube-shaped bites.

You could also develop a sleep disorder because your circadian rhythm might be thrown off due to the 38 extra minutes each day on Mars, or by a small, noisy environment, or the stress of prolonged isolation and confinement. Depression could occur.  Fatigue is inevitable given that there will be times with heavy workload and shifting schedules. 

Isolation/Confinement. NASA has learned that behavioral issues among groups of people crammed in a small space over a long time, no matter how well trained they are, are inevitable.  Expedition crews selected for a stay aboard the space station are carefully chosen, trained, and supported to make sure they can work effectively as a team for six months.  Crews for a Mars mission will undergo even more scrutiny and preparation, since they will travel farther and longer than any previous human, being more isolated and confined than we can imagine.

You will get proper nutrition, including vitamin D supplements since you can’t walk outside under the sun.  And last, good old regular exercise has been shown to keep your heart healthy, your bones and muscles strong, your mind alert, your outlook more positive, and may even help with your balance and coordination.  

  Compression cuffs worn on your thighs will help keep the blood in your lower extremities to counteract those vision changes.  Your back pain would be monitored by obtaining spinal ultrasounds.  You will perform periodic fitness self-evaluations that help researchers better understand the decline in cardiovascular function that can occur during spaceflight. Some medicines, like potassium citrate (K-Cit), may help you combat the physiological change that could increase the risk for developing kidney stones.  Bisphosphonates drugs have shown to be effective in preventing bone loss. 

By analyzing how your body changes in weightlessness and after returning to Earth’s gravity, protection against these changes for a Mars mission can be developed.  Functional task testing is in place to help detect and minimize the effects of space on your balance and performance. 

  If you have to land a spacecraft on Mars, it could be a pretty dangerous situation.  NASA has learned that without gravity working on your body, your bones lose minerals, with density dropping at over 1% per month.  By comparison, the rate of bone loss for elderly men and women on Earth is from 1% to 1.5% per year.  Even after returning to Earth, your bone loss might not be corrected by rehabilitation, so you could be at greater risk of osteoporosis-related fractures later in life.  If you don’t exercise and eat properly, you will lose muscle strength, endurance, and experience cardiovascular deconditioning since it does not take effort to float through space.  The fluids in your body will shift upwards to your head, which could put pressure on your eyes causing vision problems.  You’re apt to develop kidney stones due to dehydration and increased excretion of calcium from your bones.  Medications react differently in your body in space.  Nutrition, including eating enough, becomes important, otherwise you could compromise your health since nutrients are required for the function of every cell and system in your body.

Gravity fields, isolation/confinement, hostile/closed environments, space radiation, and distance from Earth.          

Scientists have finally captured the first image of a black hole.

After five nights of observing, the project had collected 5 billion megabytes of data. That is the equivalent of 960 hard drives containing two billion high-quality photographs.

"If we could actually fill in that final hole, show that the universe was working again in a way we arrived at by reason," he said, "that would be pretty cool.

Yet it wasn't long before scientists started seeing proof of black holes' presence everywhere they looked. Models showed that black holes could form when giant stars died.

he foundations for this discovery were laid more than 100 years ago, when Albert Einstein published the equations that defined modern gravitational physics. General relativity, first described in 1915, explained gravity as a force created when matter warps the geometry of space and time. In turn, curved space and time ("spacetime") tells matter how to move.

The new image is of a supermassive black hole located around 54 million light-years away from Earth. It sits at the center of Messier 87, the largest known galaxy.

Messier 87

Scientists have captured the first direct image of a supermassive black hole. The cosmic portrait belongs to the black hole at the center of Messier 87, the largest galaxy we know of, about 54 million light-years away. Photo by: Event Horizon Telescope collaboration