Travelers In The Night

On a recent training night with Teddy Pruyne at the controls of our 60 inch telescope on Mt. Lemmon, Arizona, this duo discovered six new Earth Approaching Objects, an inner main belt asteroid, and rediscovered an inner main belt asteroid which had been lost.

You are less likely to be injured by a space rock than you might thinkRecently in response to a question from a reader of the "Asteroid Day" blog, my Catalina Sky Survey team captain Eric Christensen, wrote a blog piece entitled "Is It Just Me, Or Are Asteroids More Dangerous They Used To Be?".

On a cold windy night, with clouds frustrating his search, my Catalina Sky Survey teammate Alex Gibbs discovered 8 new celestial visitors while observing with our 60 inch telescope on Mt. Lemmon, Arizona

A careful study of the Earth's motion in space is a key to understanding past climate change and enables us to predict future patterns of flooding and drought.Wobbles tell all.

A large fireball meteor which exploded over Cuba produced a number of interesting results.

Recently a relatively dim object, Comet P/2016 BA14 flew past Earth at about 9 times the distance to our Moon from us. It was the third closest comet approach in recorded history. This situation allowed NASA scientists to use the Goldstone Solar System Radar located in California to obtain detailed RADAR images. These revealed the nucleus of P/2016 BA14 to be about 3000 feet in diameter. It slowly spins once very 35 to 40 hours as it travels on its 5.26 year orbital path around the Sun. Observations by the NASA Infrared Telescope Facility on Mauna Kea reveal the nucleus to be as dark as fresh asphalt which means it's surface is about 4 times darker than that of our moon.

My Catalina Sky Survey Teammate Brian Africano discovered his 4th comet while asteroid hunting in the constellation of Ursa Major with our Schmidt telescope on Mt. Bigelow, Arizona. Observers with small telescopes equipped with electronic cameras are able to track Brian's 4th comet as it comes to near the orbit of Mars before it retreats into the cold dark region of our solar system not to return until 3000 AD.

A gentle method of causing an asteroid to miss planet Earth.Will spray paint save the world?Recently, NASA scientists using the giant RADAR telescope in Puerto Rico measured changes in the orbit of the asteroid Bennu. They found that a tiny sunlight pressure of 1/2 oz on this 68 million ton object has changed it's orbit about a hundred miles over a 12 year period of time. These NASA astronomers thus measured the Yarkovsky force which was first suggested by a Russian engineer more than a hundred years ago. This Yarkovsky force, named for its proposer, occurs because sunlight absorbed by an object in space is reradiated in a directional way and thus acts like a tiny rocket motor. It is likely that, over the eons, this tiny effect has changed the course of families of asteroids between Mars and Jupiter causing some of them to be sent in our direction.

NASA's Double Asteroid Redirection Test or DART for short will test methods to make a dangerous asteroid miss Earth

A pair of possibly related comets pass unusually close to Earth.It is hard to have a personal feel for the microgravity of a comet since it is only a few ten thousandths of the pull of gravity we experience on Earth. When a comet comes near Jupiter or perhaps the Earth the tiny gravity which holds it together can be overwhelmed by gravity of the larger object and the comet's structure disrupted.Astronomers have observed comets breaking up into smaller pieces as they orbit the Sun. In a spectacular example, more than 20 years ago Comet Shoemaker-Levy 9 became a beautiful string of comets before it crashed into Jupiter.Recently on two consecutive days, Comet P/2016 BA14 (PANSTARRS) and Comet 252P (LINEAR) both passed within a few million miles of planet Earth. These two objects have remarkably similar orbits which take them from near Earth out to close to the giant planet Jupiter. This situation suggests that the smaller of the two, P/2016 BA14, could be a fragment of Comet 252P which calved off of the parent o

My Catalina Sky Survey teammate Hannes Groller was asteroid hunting with our Schmidt telescope on Mt. Bigelow, Arizona when he discovered his first comet. After the Sun bakes out all of the frozen gasses, Hannes's Comet, will lose its coma and tail and become indistinguishable from one of the millions of main belt asteroids orbiting the Sun between Mars and Jupiter.

What motivates asteroid hunters?Large dangerous asteroids are still out there to find.

A tiny space rock passes through the cloud of communications satellites surrounding the Earth.

We may be able to learn about the possibilities of life on Mars by studying land forms on the Tibetan Plateau here on Earth.

I was asteroid hunting with our 60 inch telescope on Mt. Lemmon, Arizona when my Catalina Sky Survey teammate Steve Larson sent me an email requesting that I obtain some images of the asteroid 6478 Gault. Several days earlier, using mountain top telescopes in the Hawaiian islands , astronomers working with the ATLAS project reported that the perviously normally appearing asteroid 6478 Gault now has a 250,000 mile long straight tail. I added together four 60 second images which revealed a point of light with a tail which appeared to be similar to a long straight contrail left by a jet airplane high above the Earth. Images taken of 6478 Gault over the past several months suggest that it hit another object in the asteroid belt. If this idea is correct the collision fragments are what are giving this asteroid its long thin tail. Asteroid Gault is approximately 2.3 miles in diameter and thought to be a member of the Phocaea [Pho e ah] Family of main belt asteroids which themselves were formed by a violent collisio

The Catalina Sky Survey now operates three telescopes, 24 nights per month, in the Catalina mountains north of Tucson, Arizona.The Catalina Sky Survey began with the University of Arizona's 30 inch Schmidt Telescope on Mt. Bigelow. This telescope became the world leader when it was used to discover 148 Earth approaching objects in 2005. It found the most Potentially Hazardous Asteroids for the next three years running. In 2006 the University of Arizona's 60 inch telescope on nearby Mt. Lemmon received a new camera and many upgrades. In spite of the fact that this telescope was old enough for senior citizen discounts it rapidly became the world's leader in the discovery of Earth approaching asteroids. These telescopes began to make so many discoveries that a telescope which could observe newly discovered objects long enough so that their orbits around the Sun could be nailed down became a necessity. To fill this need an old unused 40 inch telescope was overhauled and installed in a new dome next to the 60 inch

The extremely remote chance that a dangerous mountain sized space rock has our number on it is what keeps my team going to our four telescopes in the Catalina Mountains north of Tucson, Arizona.

The asteroid named for Mildred Shapley Matthews was lost in the solar system for 75 years.In 1916 the 60 inch Hale telescope on Mt. Wilson, California was the largest telescope in the world. Seth Nicholson and Harlow Shapley used it to discover a 2 mile diameter asteroid. They only observed their new asteroid twice on their discovery night. Shapley named the asteroid Mildred for his one year old daughter. Nicholson and Shapley were able to find asteroid Mildred a couple of times during the month after it's discovery. After that it's 1324 day orbit around the Sun was so poorly defined that astronomers did not know where to point their telescopes to observe it and Mildred was declared "lost". Friends of Mildred Shapley Matthews would always ask her if she was found yet. In fact it was not until she was 76 years old that Dr. Gareth Williams rediscovered "lost" asteroid Mildred. After 3/4 of a century of being lost Mildred was found.

For the first time in history, an asteroid hunting team, the Catalina Sky Survey, has discovered more than 1,000 Earth approaching asteroids in a single year. They are an interesting part of our environment.

Pound for pound Saturn's moon Enceladus is the brightest object in our solar system. It is so shiny that it reflects most of the sunlight that strikes it. Since Enceladus absorbs little sunlight it's surface is 330 degrees below zero Fahrenheit. Below its icy exterior the story is very different. It appears that Enceladus has an ocean of liquid water. What Next?