Calendar of Encounters
 |
December 15 through 27, 2004 |
Apophis was in our neck of the woods (closer than .1 AU) for 13 days. Its closest approach was at .0964 A.U. on December 21. |
 |
December 27, 2004 through June 5, 2012 |
Apophis took a 7½-year retreat. It reached a maximum distance of 2.103 A.U. on August 16, 2009. |
 |
June 5 through December 28, 2012 |
On June 5, 2012, Apophis began a steady course toward its next encounter with Earth. |
|
December 28, 2012 through January 18, 2013 |
On December 28, 2012, Apophis entered our neck of the woods. Its closest approach was .097 A.U. on January 9, 2013. It left our neck of the woods on January 18, 2013. |
|
January 18, 2103 through March 16, 2029 |
On January 18, 2013, Apophis left our neck of the woods and will be out of sight, out of mind, for the next 16 years. It will re-enter our neck of the woods on March 16, 2029. |
|
March 16, 2029 |
On March 16, 2029, Apophis will enter our neck of the woods, beginning its most important encounter with Earth to date. |
 |
April 11, 2029 |
On April 11, 2029, Apophis will enter our neighborhood as its distance decreases to less than .01 A.U. |
 |
April 13, 2029 |
On April 13, 2029, Apophis will be on our porch, passing by the Earth's surface at a distance of less than 20,000 miles. |
| Coming |
Going |
Summary |
Explanation |
|
*An A.U., or astronomical unit, is the average distance of the earth from the sun, or 92,955,887.6 miles.
|
|
|
Out of sight, out of mind |
More than .1 A.U.* (9.3 million miles) away. For comparison purposes, the closest Venus ever gets to Earth is about .27 A.U. (25 million miles). |
|
 |
In our neck of the woods |
Between .01 and .1 A.U., or between approximately 930,000 and 9,300,000 miles. |
|
 |
In our neighborhood |
Less than .01 A.U., but greater than 250,000 miles. The moon is 238,857 miles away. |
 |
 |
In our back yard |
Between 25,000 and 250,000 miles away. This is within the orbit of the moon, but outside the orbits of our man-made satellites. |
|
 |
On our porch |
Between 4,000 and 25,000 miles away. We have hundreds of satellites in orbit at 23,300 miles, and hundreds more closer than that. |
 |
 |
In our face |
Less than 4,000 miles away. This is approximately the radius of the earth. Therefore, an asteroid less than 4,000 miles away from you is closer to you than you are to the center of the earth. |
|
