Thursday, February 16, 2023

Meteor Flyby 2023

 

-  3878  -  METEOR  -  likely Earth impacts?    A sizable space rock will make its closest approach to Earth in four centuries on Wednesday evening, February 15, 2023,  but it will miss us. A Valentine's kiss.


---------------------  3878  -   METEOR  -  likely Earth impacts?

-    The near-Earth asteroid 2005 YY128 will zoom within 2.8 million miles  of our planet at 3:46 p.m. PST on Wednesday closer than it's gotten to us in more than 400 years.   Listen for the swissssh!

-

-  That's about 12 times the distance from Earth to the moon.  As its name suggests, 2005 YY128 was discovered in 2005, by astronomers at Kitt Peak Observatory in southern Arizona. Over the past 17 years, researchers have mapped its orbit with a high degree of precision.

-

-   Their observations, however, haven't nailed down 2005 YY128's size. The best astronomers can give us is a diameter range, somewhere between 1,903 feet and 4,265 feet.

-

-    2005 YY128 therefore qualifies as a potentially hazardous asteroid, a designation given to space rocks at least 460 feet wide whose orbits take them within 0.05 astronomical units (AU) of our planet.

-

-   One AU is the average Earth-sun distance, 93 million miles, or 150 million km. So 0.05 AU is roughly 4.6 million miles.

-

-   If 2005 YY128 did slam into Earth, it would do serious damage.   The largest near-Earth asteroids (> 1 km diameter) have the potential to cause geologic and climate effects on a global scale, disrupting human civilization and perhaps even resulting in extinction of the species.

-

-     Smaller NEOs [near-Earth objects] in the 140-meter to 1-km size range could cause regional up to continental devastation, potentially killing hundreds of millions.

-

-    2005 YY128's close approach comes on a fateful day, the 10th anniversary of the Chelyabinsk airburst.   On February 15, 2013, a 65-foot-wide space rock exploded without warning over the Russian city of Chelyabinsk, shattering thousands of windows and causing minor injuries on the ground (mostly from flying shards of broken glass).

-

-   The incident highlighted the importance of better understanding the NEO population,  it's only a matter of time before a truly dangerous asteroid lines Earth up in its crosshairs.

-

-    As a result, scientists are getting a better and better handle on the NEO population.  NASA and its partners have found more than 95% of the asteroids out there at least 0.6 miles (1 km) wide that are thought to come within 30 million miles (50 million km) of Earth at some point. And none of them pose a danger for the foreseeable future.

-

-    On February 15, 2013 NASA was preparing for a TV segment on the flyby of a near-Earth asteroid, 2012 DA14, which was expected to zoom within 17,200 miles of Earth.    As it turned out, the videos sent showed a 59-foot near-Earth asteroid exploding in the atmosphere after surprising scientists by coming from the direction of the sun, a blind spot for telescopes and other sensors on the ground.

-

-    The resulting explosion caused millions of dollars of damage throughout Chelyabinsk and injured thousands of residents across an area hundreds of miles wide. Most injuries were caused by broken glass, although hundreds of Chelyabinsk residents suffered eye damage from the blast that briefly lit up the skies more brightly than the sun. A few dozen reported burns from the intense ultraviolet radiation caused by the blast.

-

-    Ten years later, the Chelyabinsk meteor explosion and the damage it caused underscore the need for asteroid-tracking telescopes such as NASA's “NEO Surveyor”, planetary defense missions such as the Double Asteroid Redirection Test, and research organizations like the CNEOS.

-

-     While there are currently no known asteroids that are on a collision course with Earth, unexpected objects routinely crash into the atmosphere with only a few hours notice. And in the case of Chelyabinsk, sometimes asteroids can arrive undetected through blind spots in our detection capabilities.

-

-   After the Chelyabinsk meteor exploded, infrasound sensors designed to detect nuclear detonations helped scientists determine that the blast was indeed incredibly powerful.

-

-   Initially, the explosion was estimated to be between 300 and 400 kilotons, but more recent estimates put the size at 500 kilotons. By comparison, the Fat Man nuclear warhead dropped on the Japanese city of Nagasaki during World War II had a yield of 21 kilotons.

-

-   While smaller meteor impacts and fireballs are somewhat common, impacts such as Chelyabinsk or the Tunguska event 100 years prior are far rarer due to the fact that larger objects are exponentially less common throughout the solar system than smaller ones.

-

-    Small objects hit us every day. You can go out and see meteor showers, and those are little pebble-sized objects, which are extremely numerous. That's why those impacts are common. And that's a hard thing to understand. As you go up to larger and larger sizes, the impacts become less and less frequent.

-

-     A hole, thought to be made by the fragment of the meteor in the ice of Chebarkul Lake is seen on Feb. 16, 2013, some 50 miles from Chelyabinsk, Russia. The local government reported more than 1,100 people injured, mostly by flying glass broken by the shock wave of the meteor explosion. 

-

-    2005 YY128 has been tracked by CNEOS for 17 years and its orbit has been accurately predicted to within 100 miles.

-

-   Projects like NASA's upcoming NEO Surveyor asteroid-hunting telescope will help identify and track these objects with greater sensitivity than before. Using infrared sensors, the space telescope will be able to search for multiple near-Earth objects at once.

-

-   Current NEO detection and tracking capabilities aren't quite sensitive enough to spot distant objects, but NEO Surveyor should help remedy that, enabling NASA to detect and catalog asteroids at much farther distances than current technologies enable.

-

-     NEO Surveyor is scheduled to launch in June 2028. For more information on near-Earth objects and efforts to study and catalog them, visit the CNEOS website.

-

            February 15, 2023        METEOR  -  likely Earth impacts?          3878                                                                                                                           

----------------------------------------------------------------------------------------

-----  Comments appreciated and Pass it on to whomever is interested. ---

---   Some reviews are at:  --------------     http://jdetrick.blogspot.com ----- 

--  email feedback, corrections, request for copies or Index of all reviews

---  to:  ------    jamesdetrick@comcast.net  ------  “Jim Detrick”  -----------

--------------------- ---  Thursday, February 16, 2023  ---------------------------

 

 

 

 

         

 

-

 

 

 

 

           

 

 

No comments:

Post a Comment