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Showing posts with label 2018 VP1. Show all posts
Showing posts with label 2018 VP1. Show all posts

Jun 19, 2020

A Foofaraw Over a NEO Designated 2018 VP1

Artist's concept of a near-Earth object. ImageCourtesy NASA/JPL-Caltech
Commentary 
Over the years, the tabloids as shown a propensity for raising a foofaraw over Near-Earth Objects. The Close-Approach of 2018 VP1 is only about four months away, and an internet search will reveal several clickbait stories. Many times it appears that tabloid writers pick a random asteroid and writes a "story" about it. At times one must have some background or do some research to see what the more accurate story is.

There is a low probability, 1 in 240, that the two-meter 2018 VP1 will strike the Earth's atmosphere and create spectacular fireballs on 2020-11-02. A test with the Imperial College London's Earth Impact Effects Program reports, "The average interval between impacts of this size somewhere on Earth is 0.2 years". In other words, it would be safe to assume objects the size of 2018 VP1 has impacted Earth's atmosphere since 2018-Nov-03, the date of discovery. The Earth Impact Effects Program also suggests that the fireball is unlikely to do any significant damage. NASA JPL list kinetic energy at impact from 2018 VP1[IF ANY] as ~ 0.00042 MegaTons of TNT. The Chelyabinsk event was 0.4 to 0.5 MegaTons of TNT.

Four times in the past, NEOs were observed by observers of asteroids before impact. These four asteroids(2008 TC3,2014 AA, 2018 LA, and 2019 MO) all were on the safe side when it comes to size.

 Object Date of discovery Date of Impact Size(M)
 2008 TC32008-10-06 2008-10-07 4.1
 2014 AA2014-01-01 2014-01-02 2–4
 2018 LA2018-06-02 2018-06-02 2.6–3.8
 2019 MO2019-06-22 2019-06-22 3–10

One of the programs available to the amateur observers of asteroids and comets is Find_Orb.[By Bill Gray] It is useful for calculating approximate ephemeris, determining approximate orbits, generating virtual asteroids, virtual impactors, predicting impact locations, and many other things. It should be noted IF one uses the wrong setting, one gets an incorrect solution. Find_Orb can generate an "asteroid risk corridor" with the help of Guide 9.1.[By Bill Gray]

Find_orb computing  Monte Carlo variant orbits  for the NEO 2018 VP1. One can use Monte Carlo method to  create virtual asteroids. By using orbits of  the virtual asteroids one can can see where the "real" asteroid could go. If any of virtual asteroids impact the Earth they become  known as  virtual impactors and the is 'Non-Zero' probability of  the real  asteroid hitting the Earth 

My Find_orb Setting

 Selecting perturbers All
 Epoch 2020-11-01.051
 Monte Carlo noise 2
 Physical model Include  SRP
 Filler out 3 worst observations

As a test of concept, I obtained the observations of 2018 VP1 for the Minor Planet Center. I loaded the observations into Find_Orb and had it run the Monte Carlo method all night. Find_orb generated the following files MPCOrb.datstate.txt, and  virtual.txt. These files had orbits for 129,659 virtual asteroids 200 were virtual impactors( about 0.15%). I place a copy of the virtual.txt file in the Guide directory along with a copy of impact.tdf.(Project Pluto) Then Guide could generate a map of an asteroid risk corridor.

An asteroid (fireball) risk corridor of potential impact for the NEO 2018 VP1, the orange dots is where 200 virtual impactors strike the Earth's atmosphere.

Note: Because there were more than 9 observations, I had to edited virtual.txt to do a workaround. I replace "18 of 21" with "U of O" see edited virtual.txt; this keeps the columns in the right place. I also edited impact.tdf(My) file where I can have more than one risk corridor.



Peter Thomas @ptastro1 also  this path of risk for 2018 VP1 on Twitter

Background

(as of 2020-06-13 )

 
Also see
 

Note this has been edit to fix links and know typos.

Jun 14, 2020

2018 VP1 Information Sheet-- "1 in 240" Odds of a Fireball on 2020-11-02 or ."99.59% chance the asteroid will MISS the Earth"

2018 VP1 Information Sheet-- "1 in 240"  Odds of a Fireball on 2020-11-02 or ."99.59% chance the asteroid will MISS the Earth"

This artist's concept shows a broken-up asteroid. Image: Courtesy NASA/JPL-Caltech
This artist's concept shows a broken-up asteroid.
ImageCourtesy NASA/JPL-Caltech

Throughout the year, very small rocks strick the Earth's atmosphere and creating spectacular fireballs.  Most of these rocks travel through space unknown to habitats of Earth until they strick the atmosphere.   If we are lucky, the fireball will be seen and reported.  If we are really lucky, the fireballs will be capture on film.  The most vast majority of fireballs are of no danger what so ever. Most fireballs are like rainbows in that they are cool.  Four times in the past, these rocks travel through the field of vision of an asteroid observer before impact. Observation was taken. The rocks were given designations, like 2014 AA( i.e., the first discovery of the first half of January in 2014), and the rocks "became" asteroids.  These four asteroids were on the safe side when it comes to size.

In the first half of November 2018, an asteroid was discovered and give the designation 2018 VP1.  This asteroid is very small[1.8 m - 3.9 m ( 5.90551 to 12.79528 feet) ]. This asteroid was only observed 21 times over 13 days. 

In orbit determination, one calculation what orbit will place the object in the sky where it was seen. If one knows an object's orbit, it knows where it is going and where it will be in the sky.  All observations are "imperfect," so there will be many similar orbits.  If one were to create virtual asteroids for each of the similar orbits and did a simulation, one would see over time. The virtual asteroids move apart from each other to create an uncertainty region.  The real asteroid is somewhere within the uncertainty region. When doing the simulation, if any of the virtual asteroids impact the Earth, they become virtual impactors, and there is 'Non-Zero' probability of the real asteroid hitting the Earth.  By calculating the percentage of virtual impactors to virtual asteroids, one can calculate the risk of impact.

There is a very low-risk impact 2018 VP1 will on 2020-11-02. However, it must be restarted this asteroid is very small[1.8 m - 3.9 m ( 5.90551 to 12.79528 feet) ]. We have a fireball this size about two times a year.


Find_orb computing  Monte Carlo variant orbits for the NEO 2018 VP1
Find_orb computing  Monte Carlo variant orbits  for the NEO 2018 VP1. One can use Monte Carlo method to  create virtual asteroids. By using orbits of  the virtual asteroids one can can see where the "real" asteroid could go. If any of virtual asteroids impact the Earth they become  known as  virtual impactors and the is 'Non-Zero' probability of  the real  asteroid hitting the Earth



Background

(as of 2020-06-13 )

Note: this was edited  to add links missing data formatting,  typos, replace, the image of Find_orb computing, fixing bad links .