Travelers In The Night

Since in its early history the Earth’s surface was hot and lifeless it is likely that asteroids formed in the same era as Bennu delivered the raw materials for life when they impacted our home planet long ago

On Earth, human life is enabled by plants which provide us with calories, vitamins, fuel, medicines, and oxygen to breathe. In addition, recent scientific studies indicate that plant cultivation reduces anxiety and depression and has a positive influence on diabetes, heart disease, obesity, and longevity. Perhaps this is the reason that 80% of the cultivated plant species on planet Earth are not used for any food related purpose. On long duration space missions astronauts live in close quarters isolated from the natural world where the basic activities like eating, sleeping, and attending to bodily functions are difficult and stress producing. Recent research conducted on the International Space Station suggests that space gardening helps astronauts to cope with the sterile space craft interior, allows them to combat boredom, as well as some of the other negative psychological effects of their long period of confinement. Specific examples of International Space Station gardens include astronaut Scott Kelly's first zinnia to bloom in space and astronaut Peggy Whitson's small crop of space soybeans. For many thousands of years people making long journeys have taken plants for food and recreation with them. It is likely that when humans travel to Mars they will continue this practice. The plants that Mars explorers take with them will provide a source of fresh fruits and vegetables , fresh air to breathe, and perhaps a psychological benefit that is crucial to the success of their mission.

In the distant past things in our solar system were very much more wild and violent than they are today. 4.5 billion years ago a Mars sized object called Theia impacted Earth producing our Moon. Scientists are able research this event using the current chemical compositions of the Earth and Moon.

In less than 24 hours, while observing with the Catalina Sky Survey's 60 inch telescope on Mt. Lemmon, Arizona , I discovered two 25 foot diameter space rocks that theoretically can pass less than a quarter of the Moon's distance from us. After I posted my discovery observations on the Minor Planet Center's Near Earth Object Confirmation page one of them received immediate attention, as an incoming object, and was tracked by observers at 14 different observatories around the world. Scientists at the Minor Planet Center used these data to calculate it's 926 day orbital path around the Sun, estimate it's size, and give it the name 2017 TH5. 36 hours after I first spotted 2017 TH5 streaking through the night sky it came to less than 60,000 miles from the surface of our planet traveling at 7.6 miles per second. 8 hours and 49 minutes later it passed less than half a lunar distance from the surface of our moon. If 2017 TH5 would have been on an impact trajectory with Earth humans would have had time to prepare for a spectacular light show. Approximately once every 5 years a tiny asteroid like 2017 TH5 enters our atmosphere exploding at an altitude about 3 times higher than airliners fly releasing the energy of about 5,000 tons of TNT. Asteroid hunters are well on our way towards being able to issue a warning to stay away from doors and windows should a small space rock be discovered to be on an impact trajectory with planet Earth.

My Catalina Sky Survey teammate David Rankin was asteroid hunting in the evening twilight with our 60 inch telescope on Mt. Lemmon Arizona when he spotted an unknown object in the constellation of Lyra. The largest telescopes on Earth will likely track David's discovery until it becomes too faint to observe in 2027 and catch it again when it again becomes bright enough to track in 2050. Fortunately it is extremely unlikely that it will strike Earth when it again comes close to our home planet in 2052.