2002 NT7 Will NOT Hit Earth Feb 1, 2019 - Known Since Aug 1, 2002 - Normal For Asteroids To Be Removed From Sentry Impact Table

I am getting many people contacting me scared of this asteroid, which was proved to miss Earth back on 1st August 2002! Right now, it is coming from below Earth's orbit, but not directly towards us. We are circling the sun at the same time. It crosses Earth's orbit ahead of us. By the time we get to the place where our orbits cross, it is already high above our orbit and moving away. It will be closest on 13th January, but even then it is at a vast distance of 61 million kilometers away. We already knew this back on 29 July, 2002,

This is what the Carillo observatory, a private observatory in Southern California using a backyard telescope (a 12″ Mead Cassegrain) wrote about it:

The observations from Camarillo Observatory were routine. We are one of the few private observatories in the world who continue to observe near-Earth Asteroids throughout the month, regardless of the phase of the Moon. In fact, 2002 NT7 was one of 14 near-Earth Asteroids observed that night, including one other one found on the risk pages, 2002 NY40. When used to update the asteroid's orbit, the new Camarillo observations, combined with those from NASA's Near Earth Asteroid Tracking (NEAT) program, suggested that the possibility of an impact in 2019 was in fact getting smaller.

For the next several days, 2002 NT7 was too close to the full Moon for anyone to obtain observations. Subsequent observations were obtained on July 28 and July 29, from several observatories, including Camarillo. The possibility of impacts in 2019 and 2060 were eliminated as a result of these observations. With several more observations on July 30, the asteroid was completely removed from the NASA risk page and the “all clear” was sounded on August 1, 2002. For those of us in the trenches, so to speak, the whole process was working as designed. There was never anything to worry about.

For the BBC report:, if English is a second language for you, you need to know that “ruled out” is an English phrase which means “Proved it is impossible”.

Rule out definition and meaning | Collins English Dictionary

Initial estimates of its orbit suggested there was a small chance of it colliding with our planet in 17 years' time.

However, the latest observations accumulated over the last few days have confirmed the asteroid will fly harmlessly by.

Dr Don Yeomans, of the US space agency's (Nasa) Jet Propulsion Laboratory, said:

"We can now rule out any impact possibilities for 1 February 2019." Asteroid to miss - this time around

So why does anyone still believe that it could hit Earth?

It is because of initial sensationalist reporting back on 23rd July 2002 when the story first broke, mainly in the British press, when they had far too little by way of observations to do a properly informed calculation. They just had preliminary data and didn’t know its position in 2019 even to within tens of millions of kilometers. The astronomers proved within weeks that it would miss. But the sensationalist press, especially the notorious red top tabloids in the UK still haven't caught up, or they accuse the astronomers of a cover up. This is also running in numerous YouTube videos by popular YouTube bloggers sharing the stories with their followers.

With so many sensationalist stories about it already, three months before it flies past Earth, it seems likely that it is going to build up and up to a major scare in early 2019. So I thought I'd do this article as a way to try to do something in advance to help deal with all the misinformation out there.

WHAT IS IT ABOUT THIS PARTICULAR STORY THAT SCARES PEOPLE?

We get asteroids pass by Earth at a great distance frequently. None are any risk to us, if they prove they miss, they miss, and that's the end of it. There are no known asteroids at the time of writing this with a significant risk of hitting Earth in the next century - none are considered to be of public concern. It is all done in public, and just as for, say, hurricanes, if there ever is some asteroid with a significant risk of hitting Earth we will all know about it with news stories about how to prepare for it, it would be on all the TV news, scientists discussing how to evacuate the impact area and whether it can be deflected. You wouldn't be able to miss it.

So why this particular story?

What confused the public is that the astronomers worked out a precise time it would have to hit Earth, 11.47 am on 1st February. How could they do that if they didn't already know it would hit? Doesn't that mean the 60,000 to 1 odds they published were just a sham and they already knew it would hit?

Well, no. To understand that think of a car crossing a bridge and a train that is passing under that bridge. You know when the train will pass under the bridge, to the minute. But you don’t know when the car will cross the bridge. To cross the bridge at the same time the train passes under, it has to cross it at a particular time. The car is like the asteroid. The car has already set off on its journey but you don’t know if it is a fast or a slow driver. If the average speed is 50 mph then it will arrive minutes earlier or later than if the average speed is 60 mph. Lets suppose it’s a clear road and no traffic, remote place in the countryside. All it depends on is how fast the car is driven.

The asteroid was like that car. With only a few observations they didn’t know how fast it was traveling accurately enough to know if it would pass by or hit Earth on the only date it could do it. The problem is that observations from Earth through its atmosphere are affected by twinkling and other uncertainties, and if you have a very short observation arc, you just can’t be precise about how fast it is traveling - and there is some uncertainty also about its direction of travel and its distance too.

So anyway, since 1st August 2002, we know that it won’t collide Earth in 2019, and nor will it collide with us any other time through to at least 2200.

MORE DETAIL

It was discovered on 9th July 2002 by MIT's LINEAR program and when first discovered there was a possibility of it hitting Earth. All the observations were shared publicly online amongst interested observers. You can read a history of the reports here: How A/CC broke the 2002 NT7 story

When they had very few observations, before the story broke, then the odds were very low as for any newly discovered object. The odds reached their highest point of 60,000 to 1 against it happening on 22nd July. It had just moved a tiny smidgen of distance against the background stars since discovery at that point.

Over the next few weeks the odds against this increased to 250,000 to 1 against, then eventually to 40 million to 1, then they proved it missed. There was still a tiny chance of a hit in 2060 but the odds were against this too, and by 1st August 2002, they knew that it can’t hit Earth for at least 100 years.

The observations are done by many astronomers worldwide, amateur and professional. This is a list of some of the observatories that have been involved in searching for NEO’s (note they are not necessarily all still active - and many are run by amateurs, asteroid tracking is something you can do with a backyard telescope) Observatory Links

But to this day there are frequent blog posts and also stories in the sensationalist press claiming it is going to hit Earth. When you read stories like this in Google news you need to know that Google News doesn’t filter out fake news from the UK red top tabloids:

These are papers that say the world will end probably a dozen times a year. They often just make things up. They sometimes republish articles from known fake news sites. They make up a story from a single YouTube video uploaded by someone whose real identity is not known to anyone, even the journalists, or they will make a complete story that is attributed to unnamed people on Facebook.

These tabloids are not even remotely trustworthy on matters of science or astronomy. They wouldn’t dream of doing a fake news story in matters of sport, e.g. to falsely claim that England won the world cup, nor would they do a fake obituary, to falsely claim that a famous person died, but they seem not to care at all about equally false stories of impending doom.

All of these stories are based on that earlier announcement when they had hardly any observations of 2002 NT7 yet, knew its orbit only very approximately, and were waiting for more observations from astronomers.

Click to watch on YouTube

text to the video as audio with text to speech

WHY DID ASTRONOMERS ORIGINALLY THINK THERE WAS A CHANCE, WITH ODDS 60,000 TO ONE AGAINST - AND THEN CHANGE THEIR MIND?

As you’ll see from these stories, one thing that puzzles people is why astronomers originally thought it was a risk for Earth and then removed it from the table. It’s now known that it will miss by 61 million kilometers (it’s distance in au converted to kilometers) and its closest approach is rather earlier, on 13th January 2019 (from its close approach table). This is a common thing to happen - it joined what now are over 2,000 removed objects

What puzzles the general public most of al lis that they had a very precise time and date for the impact before they removed it, 11:47 pm on 1st February. But as I explained with the analogy of a train, you have to reach the bridge at the exact moment the train passes below. A bit late or a bit early and you miss it by kilometers. If the train passes under the bridge at 11:47 pm, then that’s the only chance you have of crossing over the bridge at the same time as the train passes underneath it.

In the same way, to hit Earth 2002 NT7 had to arrive exactly at that time on that date. With more observations and a better idea of how fast it was traveling, as well as its distance and direction of travel, they found a few days later that it would “miss its appointment”. It would get there far too soon. Actually, the 8th January is when it crosses Earth’s orbit, and by 1st February it is a long way away from where Earth will be on that date. Jon Giorgini put it like this:

Two or three weeks of optical data is not enough to conclusively identify an impact years in the future. Possible hazards can be flagged, but these are actually due to the lack of orbit knowledge; the asteroid could be so many places the Earth can't help but be in some of them. These listings are possible impacts, not predicted impacts.

To predict an asteroid's orbit reliably you need radar measurements or at least optical observations spanning one (preferably two) orbit periods of the asteroid. For example, for an asteroid with an orbit period of 2.29 years, that means it should be possible to usefully predict its orbit in a positive way (where it WILL be) for a few decades after two to four more years of tracking it.

By contrast, eliminating an entry on the risk page is a negative prediction; a prediction of where it will NOT be. This can be done more quickly as new measurements come in, since large initial uncertainties shrink rapidly.

A risk-page listing is not a prediction of impact, but a statement that one is possible, primarily because it is not known for sure where the asteroid will be. Of course, lots of things are possible, most of which will not happen. It's possible I will be on top of Mount Everest 60 days from now at 12:01am but I am not predicting it. And there will come a point when my being on Mount Everest at some instant can be positively excluded ("that's impossible!").

Understanding Risk Pages

This is where it is at its closest on 13th January 2019 at 16:50 pm, we are closest to it a little after it crosses our orbit:

JPL Small-Body Database Browser

This gives a rough idea where it will be on 1st February

0.462 au or about 69 million kilometers and headed away from Earth upwards in that diagram - from the JPL Small-Body Database Browser.

The only thing is - it’s using its orbit as it is now, projected without taking account its encounter with Earth which will deflect it slightly but not much given how far away it is when it passes Earth. They have tables of figures from then on but the web interface graphical orbit I think shows its position only approximately after 13th January because it uses a simple two body solution.

Its closest approach this century is now known to be 2099 -Jan-15 11:58 when it is 59 million kilometers away (34.8 million miles)

WHY DID THEY THINK IT HAD A CHANCE OF HITTING ORIGINALLY?

So, this is how it worked.

First when they first observed it, with only a few observations, this was the range of predictions for its position for 28th January 2009 (just before the possible impact on 1st February 2019) after only 21 observations by 14th July:

Earth is that little blue dot - as you can see it is just above the arc of their predictions and there was at that time a remote chance it would hit Earth. But it could be anywhere along that arc.

In these images then a single pixel is about a million miles - it is very very low resolution. The dot for Earth is magnified - in reality it is so small that you wouldn’t see it at this resolution. It’s about a hundredth of a pixel in diameter at this resolution.

They found a 1 in 60,000 chance of an impact. If it did hit Earth, the only time it could do it was 11:47 on 1st February.

It never really had any chance at all. It's just that their calculations weren't good enough yet because they didn't have enough data. Asteroid 2002 NT7 Under Watch, But Probably Not Coming Our Way - they later found that it would be millions of miles away on that date and indeed would be at its closest a couple of weeks earlier on 13th January, and come no closer.

This is what they had for the predictions just as a result of more observations. The asteroid hadn’t changed its orbit. They just measured it better and the predictions were now, ten days later, the next day after the story broke on 23rd July:

Now there is a very short arc and it looks as if Earth is right in the middle of it

But with a bit more observations, 11 days later:

Now it’s clear it’s going to miss. But they continued to observe it, and by June 1st 2018, nearly 16 years later, this was the prediction:

And now they have a very exact prediction, of a miss of Earth by millions of miles.

I got these images from this video:

There's the usual rubbish circulating about (89959) 2002 NT7 which was at the top of impact risk tables for a few days back in July 2002 for a possible impact on 2019-Feb-01. Here's my calculation (SOLEX12) of how the uncertainty region at 2019-Jan-28 evolved as the data came in. pic.twitter.com/6gT3PJueps
— Peter Thomas (@ptastro1) June 2, 2018

tclick to show on twitter

But the video is rather dark and the planets particularly are faint and Earth is hard to see. So I increased brightness and contrast and coloured Earth in blue, in process losing some of the colour of the observations.

NEWS STORY TIMELINE

News stories timeline 2002

Many more news stories archived by date, see July section here from 9th July onwards: Cambridge Conference Correspondence Menu

STATEMENTS BY THE ASTRONOMERS

As far as the public is concerned, it just isn't worth getting worried about an object with a couple weeks of optical data showing a possible Earth encounter years from now. Sometimes, it can't even be said for certain what side of the Sun such an object will be on at the time of the listed possible impact. A few days later, additional measurements will shrink the orbit uncertainty region by a relatively large amount and the Earth will fall out of the risk zone.

When solving for an asteroid's orbit, the result isn't a single position at some time. Instead, it is a volume of space — sort of like an egg — where the asteroid COULD be with some probability. The further you get from the center of the region, the lower the probability that's where the asteroid really is.

The reason there is a probability region for an asteroid and not just a single answer is because the orbit solution is based on measurements that have errors due to the Earth's atmosphere and other factors. This limits how well the asteroid's position can be measured and combines with all the other measurement errors to create the original uncertainty space. This is especially true with optical data where atmospheric twinkling blurs out the positions. Understanding Risk Pages

Statement from Camarillo Observatory -at the time, a private observatory in Southern California. They were one of the observers that provided the observations that showed it would miss, and they used a 30 cm diameter Schmidt Cassegrain backyard telescope to do their observations. It was the 12" Meade LX200, available on Amazon for $4,600. This is something that any serious amateur astronomer with a budget into the thousands of dollars can do, join the NEA tracking programs and help with the orbit refinements. Here is what they say:

The observations from Camarillo Observatory were routine. We are one of the few private observatories in the world who continue to observe near-Earth Asteroids throughout the month, regardless of the phase of the Moon. In fact, 2002 NT7 was one of 14 near-Earth Asteroids observed that night, including one other one found on the risk pages, 2002 NY40. When used to update the asteroid's orbit, the new Camarillo observations, combined with those from NASA's Near Earth Asteroid Tracking (NEAT) program, suggested that the possibility of an impact in 2019 was in fact getting smaller.

For the next several days, 2002 NT7 was too close to the full Moon for anyone to obtain observations. Subsequent observations were obtained on July 28 and July 29, from several observatories, including Camarillo. The possibility of impacts in 2019 and 2060 were eliminated as a result of these observations. With several more observations on July 30, the asteroid was completely removed from the NASA risk page and the “all clear” was sounded on August 1, 2002. For those of us in the trenches, so to speak, the whole process was working as designed. There was never anything to worry about.

Why then did the rumor of this “killer-asteroid” sweep the news media? The answer is simply sensationalism. The predicted end of the world has always been, and always will be, a newsworthy subject. When a supposedly "Near-Earth Asteroid Expert" (who has never observed a single near-Earth Asteroid as far as we can determine) prematurely presents transient scientific data as evidence, then you have the public’s undivided attention. “Space rock 'on collision course'" read one headline in the science section of an ostensibly legitimate news site. The article went on to quote the expert as saying "This asteroid has now become the most threatening object in the short history of asteroid detection". As would be expected, other news services picked up on this "scientific" story and it cascaded like a stack of tumbling dominoes around the world. But once again, the dust has settled and the "all clear" has been sounded. This will become another "false alarm" in the memories of the public, when it should have never been news to begin with.

The public has been unnecessarily scared. You have undoubtedly seen or heard several frightening reports yourself. We received many emails from adults and children around the world, regarding the situation with 2002 NT7.

…Should there ever be a time when public concern is warranted? Absolutely! When an object is discovered that demonstrates a trend of increasing impact risk along with increasing observations (spanned over several months), then we might have something that is newsworthy. Until then, sleep easy!

ASTEROID DETAILS

Note by “Hazardous” in the details I’m about to share, they do not mean as in “Hazardous in the next 100 years”. It is an astronomical technical term that just means its orbit comes within 19.5 lunar distances of Earth. Some approach Earth from within but don’t reach our orbit, some from beyond, and some cross Earth’s orbit but above or below it and can’t hit us right now. Some are in stable resonances in horseshow orbits for centuries and one is a quasi moon that orbits Earth at a distance of 100 lunar distances and at its closest 38 lunar distances and another is currently orbiting a third of our orbit ahead of us in the L4 position. None of those have any possibility of hitting us for many centuries.

Only a few percent will hit Earth ever. Most end up hitting the sun after several flybys of other planets. Others hit Jupiter, or are ejected out of our solar system by Jupiter and a few of them hit Mars, Venus, Earth, or other planets eventually - but most not any time soon. If they are going to hit Earth they will usually do so within 20 million years. But it could easily be a million years from now. Meanwhile new asteroids come along from time to time, many from the asteroid belt or they could be extinct comets, to take the place of the ones that are removed by hitting the Sun, Jupiter, ejected from the solar system or hit other planets.

With that background the details are here: Asteroid 89959 2002 NT7.

More techincal details are here - notice that the close approach table has the same value for the minimum and maximum position in 2195 to four decimal places and only one digit difference on the fifth. They also know the times of the flyby accurate to less than a minute through to 2195. This shows that the errors are minimal and they have a very precise understanding of its orbit. The figures are in au and you'll notice that for instance in 2060 it is now expected to fly past at a distance of half an au. That means half the distance to the sun. To convert to kilometers or miles or whatever you can type 0.497327240929044 au in kilometers into Google.

EVERYTHING IS IN THE OPEN

And no, they aren't hiding anything, that's just something from movies, never happens in real life, not for disasters. Would they hide warnings about an approaching hurricane? Of course not, they give al the details they can and save thousands of lives. It would be impossible anyway. Astronomers worldwide are involved in tracking the asteroids.

It's all done in the open through public electronic circulars from the minor planet center and other online sharing, on pages mainly read by experts. You can read them for yourself here, though they are very technical and won’t mean much if you aren’t expert in the field of astronomy (as an amateur or professional) and asteroid tracking: A/CC News.

All the 2002 NT7 observations were shared there from when it was discovered on 9th July 2002. But it only broke as a story in the world media after someone who was following the page sent an announcement to them. It was not an official IAU announcement because it was only barely above the background risk of asteroids at the time and it wasn’t thought noteworthy enough to be of public concern.

It is normal to remove objects from the sentry table. They now have over 2,000 removed objects. (Many of those would have had only the remotest chance of ever hitting Earth and so never got to any kind of an alert level).

Sentry: Earth Impact Monitoring - removed objects

It’s the normal thing indeed, for objects to be removed.

When first discovered they may have a small chance of hitting Earth with a big error ellipse that includes Earth.

As they find out more the ellipse shrinks. Normally that leads to them working out that it misses Earth. Sometimes Earth remains inside the ellipse and so the risk can appear to go up for a short while, as happened for 2002 NT7, but as the ellipse shrinks further they find it misses.

The minor planets center does an immediate prediction - and other astronomers might also. The CNEOS funded by NASA has the most elaborate models, taking all sorts of things into account, even minor effects like effects of heating on the asteroid as it spins, and the Sun, all the planets and the Moon, larger asteroids and everything.

Theirs is the most accurate and final version of the prediction. Then others rely on them - and their predictions work. The asteroids fly past Earth as expected to the minute. None of this even can be hidden from anyone. NASA certainly can’t do it by itself, and they depend on their predictions to tell astronomers where to look to do their observations.`

2002 NT7 is just large enough to have some global effects. It would produce a crater perhaps 10–20 km in diameter. But it has missed its appointment with Earth for the next century at least - and the odds are against it ever hitting us as most such asteroids hit the Sun, Jupiter or are ejected from the solar system over timescales of millions of years.

For other details see

In actuality the largest asteroids with global effects of diameter 10 km and upwards are now completely ruled out, we know them all. The ones of 1 km upwards are almost completely ruled out, using discovery statistics and estimation methods they have worked out that we have found 97% of them already. We find the remaining ones at a rate of about once a month, but that should speed up with the Large Synoptic Survey Telescope in the early 2020s. By the end of the 2020s we should have found nearly all the asteroids large enough to have even minor global effects. It is not likely now that any are going to hit us by 2100, but if any are we are likely to have plenty of warning to deflect them or at least prepare.

Long period comets can't hit us without warning. They can be spotted many years in advance, if they are kilometer scale, at least three years but most likely more than that. They are also currently very rare. The closest any long period comet came was Lexell's comet in 1770 and it passed at a distance of 6 times the distance to the Moon- it was actually deflected for one orbit by Jupiter into a short period comet, and that's a likely scenario - long period comets approach the inner solar system at steep angles often and they cross the plane of Earth's orbit in only two places. It's the same for most shorter period comets too. For instance Halley's comet crosses the plane of our orbit close to Venus and there is no possibility at all of it hitting Earth any time soon, most likely never. The reason we get debris from Halley's comet as a meteor shower is because the tail of the comet is blown out away from the sun as far as Earth and further, but that's only fine debris.

For the background to this and much more information, see also:

This is from my

How we know 2002 NT7 will not hit Earth on 1st February 2019 - and why it is normal for asteroids to be removed from the Sentry Earth Impact Monitoring table

PREAMBLE - THE REASON FOR OUTREACH TO HELP SCARED PEOPLE

I'm doing this as part of my series of posts to help people who get scared by these stories. Many of them are very young, we help children as young as 13 in the Facebook group and hear of much younger ones aged as young as 8 from parents and from their scared comments on YouTube videos. They are often absolutely terrified by these stories and sometimes suicidal. We also hear from adults who just don't have a strong background in physics or astronomy, and have no way to asses these stories. Many of those we help are diagnosed with anxiety, depression, PTSD, generalized anxiety disorder and so on, and are receiving treatrment from health professionals, both talking therapies such as CBT and drugs such as prozac. While some are anxious by temperament already many of those who contact us say they only began to get scared after reading one of these stories and wish they could somehow roll back to their happy childhood before they read the story. Even once they understand the debunks intellectually they continue to get flash-back panic attacks and this can continue for many weeks or months, especially so for the ones who try to go it alone and don't like to involve health professionals. We advise them all to contact health professionals, but a few in a hundred will just say they want to handle it on their own, and there is nothing one can do except encourage them from time to time to reconsider this. They often report that they vomit with fear, a reaction that most of us don't realize even happens when you are extremely scared and as I said from time to time we hear from people contemplating suicide. All about utter codswallop and nonsense, if only they had the science smarts to evaluate the stories themselves!

What makes these stories worse is that Google News, Apple News, and Facebook trending feature the sensationalist stories from the Red Top Tabloids from the UK as "news" with nothing at all to indicate that they often publish inaccurate news stories, some of them even republished from known fake news websites, or based on a blog post or YouTube video or facebook post by an unnamed individual. To a young child or an adult without a good science education, they come to trust, say, Google News. For them, these stories that they see in their mobile devices are just "News". No, they are not, some of them are just fake news or absurd sensationalism. Sadly you can't trust these sources to serve you up reliable and accurate news reports.

This is part of a whole ecosystem of fake doomsday stories. The more popular YouTube channels can earn thousands of dollars a month each from ad clicks on doomsday videos, which tend to go viral and get widely shared by scared people. It's likely at least a million dollars a year of ad revenue on YouTube from fake Doomsday videos by my rough calculations based on what we know so far. And the journalists have found that doomsday stories get them many more clicks and views. I think most of them are not aware quite how much this affects their most vulnerable readers - if you are a journalist, remember nowadays a young child even as young as 8 may see your news story in their mobile device. Meanwhile with all their drive to do something about fake news, for some reason Google News, Apple News and Facebook Trending are doing nothing at all to flag the fake doomsday news from the UK red top tabloids. If you are a journalist you can also help by running debunking stories.

if you want to help make a difference, you can sign and share these petitions- and do have a look at the comments to get an idea of the scale of the problem. Click “Join Conversation” to see more of them.

THE REASON FOR OUTREACH TO HELP SCARED PEOPLE

SEVEN TIPS FOR DEALING WITH DOOMSDAY FEARS

If you are scared: Seven tips for dealing with doomsday fears which also talks about health professionals and how they can help.

MORE DEBUNKS

More debunks: List of the articles in my Debunking Doomsday blog to date

Search the debunks using e.g. site:debunkingdoomsday.quora.com Nibiru - Google Search

Doomsday Debunked wiki: Doomsday debunked

Twitter feed: DoomsdayDebunked (@DoomsdayDebunks) | Twitter

Facebook group Doomsday Debunked has been set up to help anyone who is scared by these fake doomsdays.

TOP NEWS WITHOUT THE FAKE SENSATIONALIST NONSENSE

I’ve done a custom search engine to search top mainstream reputable news sites. Various versions, see:

Search Top News

You can also make your own custom search engines like that - easy to do in Google, I explain how I did it in New: Google News Without All The Nonsense - Top Astronomy News - Top Space Mission News - Top Science News - Top News

IF YOU NEED HELP

Do message me on Quora or PM me on Facebook if you need help.

There are many others in the group who are available to support scared people via PM and who can also debunk fake Doomsday “news” for you if you get scared of a story and are not sure if it is true. See our debunkers list

If you are suicidal don’t forget there’s always help a phone call away with the List of suicide crisis lines - Wikipedia