Travelers In The Night

Every year the Monsoon summer rains come to the American southwest in July and August. After the threat of wild fires has been rained out, monsoon time continues to be difficult for asteroid hunters. Even so this season is used to find interesting objects and to prepare our equipment for the clear skies we hope for in the fall.

The first unmanned test flight of the new NASA Orion Spacecraft went perfectly. It made two orbits of the Earth traveling as far as 3600 miles above the surface of our planet. Its path took it nearly 15 times higher than the international space station. This is further than any spacecraft designed for humans has flown since the Apollo era.

There may be as many as a trillion small icy objects in the Oort cloud near the outer edge of our solar system. Very rarely one of these frozen ice balls is jostled by the gravity of a nearby star causing its distant path about our Sun to be transformed into one which takes it near the planets we know. Most of these small comets pass unnoticed by humans although occasionally one can become bright enough to be seen with the naked eye.

Humans know of approximately half million main belt asteroids orbiting the Sun between Mars and Jupiter. We have also found approximately 11,000 Earth approaching asteroids. Members of these two groups can be recognized by briefly observing their motion since their paths about the Sun are very different. Jupiter Trojans, on the other hand, occupy a point either 60 degrees in front or behind Jupiter as it moves about the Sun. Their orbit around the Sun takes about 5 and a half years so short pieces of one of their orbits can mimic the path of an Earth approaching object. When Jupiter Trojans are opposite to the Sun, their little full moon faces are pointing towards Earth. When they are in this position in the sky we have to sort through a number of them so we can separate them from real near Earth objects.

Our star is only one among hundreds of billions in the Milky Way galaxy which itself is only one of a hundred billion or more galaxies in the known universe. How can it be that humans are the only creatures to look at the night sky and wonder about who else is out there? Perhaps taking a close look at the human race is a way to find extraterrestrials.

Four days after it made its closest approach to Earth, I found a 10 foot diameter asteroid with the NASA funded University of Arizona 60 inch telescope on Mt. Lemmon. At that point it was 838,000 miles from us and was moving away at about 3 miles/second. Previously, It had been about half the distance to the Moon from planet Earth. This small asteroid orbits the Sun every 349 days on a path which crosses our orbit twice a year. Calculations by the NASA - JPL group indicate that it can come within 2 Earth diameters of us.

Some stars can have flares which can cause them to more than double in brightness in a few minutes. Fortunately our Sun does not do that and the Earth's atmosphere and magnetic field protect humans from the smaller flares which do occur on our star. In 2020 the Sun is beginning a new solar cycle and by 2024 we should be seeing solar flares with increased frequency. It will be important to put our electronics into a safe mode should a major solar flare occur.

2014 US7 is called an Aten [Ah tin] type of asteroid. The first of its type was discovered by Dr. Eleanor Key Francis "Glo" Helin in 1976. She was an American astronomer who discovered more than 800 asteroids and several comets. During her long career she made the transition from glass plates to the latest electronic detectors. She was a leader in the establishment of the Near-Earth Tracking Project which discovered more than 36,000 asteroids.

Phaethon (Faith on) is a strange, 4 mile diameter, blueish asteroid. It travels on an orbit which comes so close to the Sun that its exterior is heated to 1,500 F. When you go out to view the Geminids in December you might consider what this space rock has to tell you.

My Catalina Sky Survey teammate Hannes Groeller was asteroid hunting in the constellation of Pegasus with our 60 inch telescope on Mt. Lemmon, Arizona when he discovered a Potentially Hazardous Asteroid . Rest assured that astronomers will continue to track Hannes' discovery to make sure that it does not become a threat to humanity as it crosses the orbits of Earth and Mars.

Marie Curie's discovery of radioactivity started humans on a path which so far has skirted annihilation and has led to cures for cancer and the exploration of the distant regions of our solar system.If you want to get an idea about what our knowledge of the solar system would be like without Radioisotope Power Systems, go to a used bookstore or the library and find an Astronomy text book from the mid 1970's and well as a current one. Look up the planets in both.

The human thirst for knowledge about our mysterious next door neighbor is about to receive more than a sip from robotic emissaries launched in 2020. Recently a group of scientists point out that by having astronauts fly by Venus on their way to Mars and/or on their way back to Earth would save fuel, weight, and cost and allow humans to return home after only a month long stay on the red planet. Additionally when the crew is near Venus they would be able to pilot drones in the Venusian atmosphere and to study a world where global warming has fundamentally changed our sister planet.

It appears that the human population is at more at risk from smaller rather than larger Earth impacting asteroids.During the past 20 years more than 550 small asteroids ranging in size from 3 to 60 feet in diameter have entered the Earth's atmosphere. They had impact energies ranging from 5 to 500,000 tons of TNT. Newly released data show that most of them exploded high above the ground doing little or no damage at the surface.

My Catalina Sky Survey teammate Hannes Groeller was observing in the constellation of Boötes with our 60 telescope on Mt. Lemmon, Arizona when he discovered a potentially hazardous asteroid which had evaded being spotted by the asteroid hunting community on four previous occasions.

Every month we discover small asteroids which come closer than the Moon. There are probably 20 million asteroids in this size range which come near the Earth. A few of these may eventually impact our planet. Those that do are likely to explode high in the atmosphere producing a supersonic boom. We are not more likely to be hit by a small asteroid than we have in the past. However, we are becoming more likely to be able to provide a tornado like warning for people in the affected area to stay away from doors and windows.

If we don't place some new space weather observing satellites into orbit it is possible that you will wake up one day to no electricity, no cell phone, no way to pump gas, and no way to pay for things with a credit card.

Recently my, University of Arizona, Catalina Sky Survey, teammate, Jess Johnson, was searching for Earth Approaching asteroids when he discovered a faint slow moving object in the night sky. Six nights of followup observations revealed that this new object's path is out near the planet Neptune. It takes approximately 173 years for it to travel once about the Sun so it will take observations over the next few years to pin down its orbit. With a diameter of approximately 43 miles it is much larger than the Earth approaching objects we normally encounter.

If the current trend in 11 year solar cycles for the past 50 years continues, we can expect lower than average solar activity and the Earth will continue to receive less than average amounts of solar energy over the next decade. Don't expect lower levels of solar radiation to save us from global temperature increases caused by humans dumping vast amount of carbon dioxide and other green house gases into our atmosphere.

Many scientists have been started on their career paths by an interest in astronomy and the mysteries of space. As technology has developed it has become more difficult for students to be involved in hands-on scientific research. Target Asteroids provides an opportunity for students to participate in real scientific research and to have a chance to discover and name an asteroid.