Something big just hit Jupiter | Hacker News Reader

Something big just hit Jupiter

universetoday.com

214 pointsRickJWagner106 comments

Thanks, Jupiter!

Jupiter is thought to be one of the reasons earth is so hospitable, with its high gravity protecting inner planets from some comets and space debris [1].

I, for one, think we need a Jupiter appreciation day.

https://earthsky.org/space/is-it-true-that-jupiter-protects-...

Is that something people searching for ET life look out for? Systems with a potentially habitable planet + at least one large celestial object to draw debris towards it and away from the potentially habitable planet?

Are we able to see far-away systems in this level of detail? I know we can calculate number of planets and rough size/makeup, but are we able to tell that Planet A is in the habitable zone and Planet B is 300x+ the mass of Planet A, etc?

We can for a lot of systems. The shorter the orbital period, the easier they are to detect, however, and to detect Jupiter from a nearby system we’d need to be very lucky.

Yes, at least using the transit method.

Sometimes, we do use the Doppler shift caused by a planet pulling the star towards or away from us. That works as long as the orbital plane is not perfectly perpendicular to us. However, it only works for large planets (and reasonably sized stars) that have sufficient gravity to make the star move fast enough to see the light shift red or blue. An earth-mass planet would be undetectable compared to a Jovian planet.

The transit method requires the orbital plane to be perfectly on axis so we can observe an eclipse as the planet passes between the star and our telescope. This is rare, but works for even small planets, as long as the angle is right. And if one angle is right, it's likely that others will be close enough as well; a large planet can also be observed. In systems that are at the right angle, Kepler often found several planets:

https://en.wikipedia.org/wiki/List_of_exoplanets_discovered_...

Hmm, I wonder if there are lots of variables that go into "likelihood of being hit by asteroid" - e.g. the size of the central star in the first place, and the resulting radius of the hab zone.

It's also of not: if earth hadn't been hit by at least some asteroids, it mightn't have any water.

Given that Western civilization worshiped Jupiter as top god for a thousand years, you would be in good company historically [1] to have have a Jupiter appreciation day.

[1]: https://en.wikipedia.org/wiki/Jupiter_(mythology)#Religious_...

So do many Eastern civilisations...

Ok...

In India, Jupiter is called as "guru" (Sanskrit:बृहस्पति). बृहस्पति roughly translates to "guru" of the gods.

Interesting. Is there any connection in Sanskrit for that word to Dyaus [1], as that deity was an equivalent of Zeus/Jupiter

[1] https://en.wikipedia.org/wiki/Dyaus

Not because they understood the gravity thing, though. I've always thought civilisations that worship the Sun have the right idea.

Jupiter, along with Zeus, Tyr, and a whole host of others are cognate with the Proto-Indo-European *Dyḗus ph₂tḗr, literally 'sky father'.

The sky father was the chief god of the steppe people that lived north of the Black and Caspian Seas during the Neolithic into the Bronze Age, so 'Jupiter' as such was worshiped for 2000 years before the Greek speakers called him that.

As these people (according to all the currently most accepted archaeological and linguistic evidence) are the ancestral culture of most of Europe, Iran, and India (with the exception of the native Dravidians), it makes sense the Greeks as well as most of the religions of Europe and southwest Asia also worshipped him.

I think by steppe people, you are referring to Indo-Europeans (Aryans). There is also a sky-god in Tengrism (Mongols, Turks). But are either of those actually referring to the planet Jupiter?

Nah, the naming of the planet came much later, I don't think the planet itself was ever worshipped.

And the Proto-Indo-Europeans are not the Aryans - the Aryans were a much later daughter culture in Western Afghanistan, Northern Iran and India, and probably the folks that had the beliefs outlined in the first pages of the Rig Veda.

The steppe people I am referring to are the people of the Yamnaya culture and related peoples within their horizon. The Mongols and Turks were relative late comers to the western steppes.

Pretty sure "Aryans" is a 19th and 20th century term used for the Indo-Europeans (or roughly approximating "Indo-Europeans"), hence the association of "Aryan" and 20th century race ideology (e.g., theories of an "Aryan homeland" was in Germany, that the Germans were a pure Aryan race, etc).

The racialists of the late 19th Century and early 20th co-opted the term, but there was a real peoples that really called themselves 'Aryans'. They weren't blue eyed blonde-haired, that's for sure, and the weren't at the root of Europe either. Like I said, they were a central Asian daughter culture. They probably spoke Indo-Iranian and their beliefs were later written down in the Riga Veda as well as being a component of Iranian Zoroastrianism.

('Aryan' is cognate with the proto-Indo-European 'h₂éyos')

> They weren't blue eyed blonde-haired, that's for sure

ok but the world-wide "suppress melanin/blue eyes" gene emerged in that same part of the world (north of the Black Sea) some 10,000 years ago, so it seems that the Aryans could have been as blue eyed as anybody.

https://web.archive.org/web/20091101055254/http://www.telegr...

well, possibly, but as they are probably the ancestors of many North Indian, Iranian, and Afghanistani peoples that gene didn't stay dominant for their line. (Though I guess it shows up in that region now and again).

And they certainly weren't the 'Aryan ideal' as pictured in racist propaganda.

I agree, I wasn't disputing that there were real people who self-identified with the term, I was contesting your correction that "Aryan" solely refers to these people. You might counter that the overloaded meaning is invalid for whatever reason, but (1) meanings of the propriety of words are boring and subjective and (2) I'm only saying there exists an overloaded meaning, not that everyone will find it valid nor that it excludes the validity of other meanings.

As an aside, I recently discovered (from my new Iranian neighbors) that the term "Aryan" is cognate with "Iran" the country. "Iran" in Persian means something like "Land of the Aryans", and that in 1935 the government of Iran asked its diplomatic partners to refer to it as Iran instead of Persia because of the popularity of Aryan racial ideologies.

Ah gotcha, yeah, the notion of the 'Aryans' as the ancestors of Europe was a common misconception of early European archaeology even when it didn't have the racist propaganda connections.

The etymology of Jupiter is also fascinating. https://www.etymonline.com/word/jupiter

> also Juppiter, c. 1200, "supreme deity of the ancient Romans," from Latin Iupeter, Iupiter, Iuppiter, "Jove, god of the sky and chief of the gods," from PIE dyeu-peter- "god-father" (originally vocative, "the name naturally occurring most frequently in invocations" [Tucker]), from deiw-os "god" (from root *dyeu- "to shine," in derivatives "sky, heaven, god") + peter "father" in the sense of "male head of a household" (see father (n.)).

Greek and Sanskrit also had similar deities:

> Compare Greek Zeu pater, vocative of Zeus pater "Father Zeus;" Sanskrit Dyaus pitar "heavenly father."

Basically the Greeks dropped the `-pater` bit and `Zeus` remained.

Whether or not these deities were similarly associated with the planet Jupiter is a different question though.

> Whether or not these deities were similarly associated with the planet Jupiter is a different question though.

Very doubtful, those names are modern applications to the planet. Although, there is zero doubt they were aware of and cognizant of the visible planets and their motions and no doubt had important names for them, it wasn't what western astronomers called them, almost certainly.

Also Dyaus Pater was a god of the daylight sky for the most part, which in the steppes, as you can imagine, made him pretty important and omnipresent.

Hm, Jove and Yahwe are pretty close i'd say.

We have no idea how the Hebrew tetragrammaton YHWH is supposed to be pronounced. And there are no etymological common roots between this semitic root and the attested Indo-European origin of Iove.

It's possible that the Yahweh vocalization has been influenced by the Roman Catholic church in order to "romanize" christianity

I've been researching these cultural echoes of the Proto Indo-Europeans online for some time now; it's fascinating that over a billion people (Catholics, etc.) use roughly the same term 'Deus Pater' to describe their supreme deity up through the modern day without full cognizance of the concept's historical roots. Sky father worship may be the most highly conserved human cultural idea of all time.

Do you have any suggestions for reading material (ideally academic in book form) that covers the archaeological and/or linguistic reconstruction research in depth?

The best accessible archaeology reference I can recommend is "The Horse, the Wheel, and Language", and that book can guide you to many other resources.(https://press.princeton.edu/books/paperback/9780691148182/th...)

Though the research is a tad dated since we have more genetic evidence since it was written, and there are many disputes about the author's assertions about the timing of the advent of horse riding, it still stands up very well. AFAIK the genetic research made since the book's publication has only strengthened his archaeological and linguistic arguments.

Thank you very much! I will order it.

Doesn't exactly fit your request, but maybe consider reading the book Suns of God too:

https://www.amazon.com/Suns-God-Krishna-Buddha-Unveiled/dp/1...

Isn't that Thursday every week?

I suggest Thursday!

Wouldn’t Wednesday (Woden’s Day) be more appropriate?

Thursday is literally named after jupiter in latin and latin based languages (french, spanish, etc)

The Germanic Thursday is “Thor’s day”, I guess Jupiter is more like Thor than Odin/Woden.

Old English/Norse.

to be more specific, yes. I was going with the least specific branch of the tree that was still different and widely recognizable.

Even "Thor's day" is linked to Jupiter, in that Thor and thunder gods were the equivalent of the thunder god Jupiter: https://en.wikipedia.org/wiki/Thursday#Thor's_day

Ha, just now I realized "Jeudi"... lucky day today!

But just some romance languages. Portuguese does not.

All seven days of the week are named after the classical planets, or the Germanic/Norse equivalent of the Roman gods: Mercury (Wednesday, Woden/Odin's day), Venus (Friday, Frig's day), Mars (Tuesday, Tiw's day), Jupiter (Thursday, Thor's day), Saturn (Saturday), the Sun (Sunday), and the Moon (Monday). Some make more sense in other languages, e.g. French has Lundi (Lune/Moon), mardi (Mars), mercredi (Mercury), jôdi (Jupiter), vendredi (Venus) (samedi refers to the Sabbath and dimanche to God, though).

The naming of the days of the week after the planets isn't obvious. The English names of days are taken from the old norse gods, as you say, but the association with the planets goes back to Roman times and it's rather obscure.

Here are the names of the days of the week and their associated planets (and the old norse gods that give them their English names, as you list them too):

  Monday    --> Moon (Moon's day)
  Tuesday   --> Mars (or Tyr's day) 
  Wednesday --> Mercury (Wodan's day)
  Thursday  --> Jupiter (Thor's day)
  Friday    --> Venus (Freya's day)
  Saturday  --> Saturn (duh)
  Sunday    --> Sun (and duh)

Why are the days associated with celestial bodies in that order? Mars is not between the moon and mercury, in the sky. Saturn is furthest, not closes to the sun! But this was not exactly known in ancient times. Rather, the luminaries (the sun, the moon and five planets) are ordered, in the Ptolemaic universe, according to their apparent speed in the night sky, from slowest to fastest, which the ancients took to mean corresponded to a planet's distance from the Earth (since the farthest-away planet had to make a longer orbit):

  Saturn
  Jupiter
  Mars
  the Sun
  Venus
  Mercury
  the Moon

But this is still not the order in which the days of the week are ordered, according to their association with a luminary. Saturn's day, Saturday, is not before Jupiter's day, Thursday, in the week!

The hidden detail is that the ancients regarded the luminaries as "ruling over" an hour of the day. Each day took the name of the luminary that ruled over its first day. So the first luminary, Saturn, the furthest from the Earth, ruled over the first hour of the first day of the week, which for the ancients was Saturday. The second luminary, Jupiter, ruled over the second hour and so on, for all 24 hours in a day, in a repeating cycle.

Since there were 7 luminaries, the cycle repeated three times in each 24-hour day, with 3 hours left over. When a new day began, the luminary that ruled over its first hour was the luminary three over from the one that ruled over the first hour of the previous day. So the day ruled over by the first luminary, Saturn, Saturday, is followed by the day ruled over by the luminary three over from Saturn, the Sun: Sunday.

To mess things up even more, the ancients had a second, "dark" day, and a dark week, where the days were named by the luminary that ruled over the first hour of nighttime (where the ordinary days were named after the luminary ruling over the first hour of daylight). So for instance, when the "light day" was Thursday, the "dark" day was Monday. The dark week starts on the 13th hour of each day (the 13th hour from sunrise). I have no idea how the ancients managed daylight savings time :P

Anyway our days of the week have a tinge of ancient astrological magic to them. Remember that to the ancients, astrology and astronomy were still the same thing. Our knowledge became more practical as time went by and less magickal. Or, like I like to say, we finally found a magic that works.

I think Jupiter was also Zeus, but not AFAIK Odin.

https://www.ancient-literature.com/are-zeus-and-odin-the-sam...

Odin is not Zeus, although in he assumed a lot of Zeus's place in the Norse pantheon.

The mostly forgotten proto-Germanic god Tyr's name however is cognate with Zeus, Jupiter, Dyaus, and the other sky father gods.

Wednesday is the planetary day of Mercury, who is more cognate with Odin.

In Hindu culture, Jupiter is known as Brihaspati, and Thursday is known as Brihaspati-var (the day dedicated to Jupiter).

I suggest Saturnday

There are some astronomers who believe that the converse is also true - Jupiter also flings in Kuiper-Belt Objects into Earth-Crossing Orbits. The results are complicated, https://academic.oup.com/astrogeo/article/49/1/1.22/306978

Relevant quote,

> The flip side of the coin is also true, however — for an object to threaten the Earth, it first has to have an Earth-crossing orbit. Were Jupiter absent, there would be far fewer short-period comets, and it is likely that the asteroid belt would be far less heavily stirred, though it is also true that, without Jupiter, the asteroid belt would no doubt look very different! Every encounter between a small body and Jupiter is random — it throws objects inwards as well as outwards, and can just as easily place objects onto an Earth-crossing orbit as it can remove them from these orbits. Therefore, it is clear that at least some of the objects that hit the Earth would not have done so, had Jupiter not played a role.

> Whether Jupiter acts as a friend or a foe comes down to the balance between the two effects discussed above — does Jupiter provide more of a shielding effect, or is the contribution to the terrestrial impact flux so enhanced by the objects it throws our way that this outweighs its defensive work? In order to examine this balance, we are in the process of a series of detailed integrations, following the behaviour of hundreds of thousands of potential impactors in a range of theoretical solar systems. Given that there are three reservoirs of potentially hazardous objects (the Oort Cloud, the Edgeworth-Kuiper belt, and the asteroid belt), our study will be looking at each of these reservoirs in turn.

It is currently unclear whether the net effect is harmful or beneficial. But what we do know is that the fact that we are dyadic system (i.e. our moon is arguably the size of a planet - and we exist in a pair with it) has protected us during Sol's younger and more active days. More specifically it protected us from ending up like Mars with a stripped away atmosphere. This hypothesis is fairly well studied and is held to be very likely to be true.

Our moon, along with Jupiter, may also act as interference for the Earth w.r.t. Earth-crossing asteroids. There are arguments against this because of the smaller size of the Moon, but there are also some analyses for this - given that the asteroids are affected by the Moon's gravity, and even though the Earth-Moon Barycentre lies within the Earth, the combined system may afford some protection. (i.e. asteroids are more likely to have more near misses given the displacement of the barycentre from the centre of the Earth). But this is a guess, and more study is needed.

Papers,

When the Moon had a magnetosphere - https://www.science.org/doi/10.1126/sciadv.abc0865

The timeline of the Lunar bombardment - revisited. - https://arxiv.org/pdf/1801.03756.pdf

The Late Heavy Bombardment in The Inner Solar System: Is there Any Connection To Kuiper Belt Objects? - https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.61...

Bashing holes in the tale of Earth’s troubled youth - https://www.nature.com/articles/d41586-018-01074-6

If it hit Jupiter on the inner orbit side, then whatever struck the outer planet already missed us (if it was ever within our orbit to begin with). Since we can see the impact from Earth, it must have struck the inner orbit side.

It could have been captured from another angle and swung around wildly before its orbit finally intersected the "surface" of Jupiter.

I think there would be a lot of push back from christian based religions. They would be offended at the mere suggestion. So if you're really wanting this, be prepared for a fight.

> I think there would be a lot of push back from christian based religions. They would be offended at the mere suggestion.

Perhaps from some of the fundamentalist sects, but unlikely from the liberal mainline branches; we'd recognize "Jupiter" as referring to the planet, not the Roman name of the Greek mythological Zeus.

Link to the impact video https://www.youtube.com/watch?v=ImVl_TfTFEY

Is that real time? Not sped up / slowed down?

Sounds to me like it's real time: https://apod.nasa.gov/apod/ap210917.html

If you look at the frequency of the earth atmosphere flicker, it looks like roughly real time.

If that's realtime, how is it possible for something so big to dissipate so quickly? I would've thought the flash would take anywhere from minutes to days to dissipate.

The feeling is strange, yes. It disappeared in a cloud, and in the storms behind it. The word 'Hit' should be taken in the same way as an airplane hitting a sea of clouds.

> Based on the images and video provided observers, the object’s diameter is estimated at 20 meters (ft).

A 20 meter object created a fireball that could be observed from earth?

Yeah, stood out as surprisingly small. Jupiter diameter is about 140,000 km so isn't that flash at hundreds of kilometers across? I got 21 pixels while the planet is 500 pixels so 21*14000/500 = 588 km . Blurring might expand it though so in reality could be smaller.

Tunguska was estimated 50-60 m diameter though I guess velocity could tend to be higher at Jupiter? https://en.wikipedia.org/wiki/Tunguska_event

Nobody spotted the error?

21*140000/500=5880 km

Jupiter's high gravity likely meant that it hit at a greater velocity than it would have if it impacted Earth.

As a rule-of-thumb, asteroids hit at or above escape velocity. Earth's is 11 km/s, Jupiter's is 60 km/s.

Energy is the linear product of mass, but quadratic product of velocity. Hence, the ratio of an impactor's energy hitting Jupiter vs Earth is not 6:1, but 36:1.

Mind you, this is nothing compared to what happens if even a mere pebble hits a neutron star!

I think the proper energy to calculate is that of an object falling into the Sun, being intercepted in its fall by the object it impacts.

Solar escape velocity near Jupiter orbit is only around 18km/s which is quite a bit less than Jupiter's own escape velocity.

Objects aren’t falling into the sun from infinity, as gravity decays according to an inverse square law the sun imparts relatively little kinetic energy to a Jupiter impactor relative to Jupiter.

To match the calculations by JPL/NASA, assume that the objects are falling into the Sun from infinity.

>>Mind you, this is nothing compared to what happens if even a mere pebble hits a neutron star!

What would happen if a pebble hit a neutron star? I'd like to imagine the pebble would vaporize at contact or even before it(temperature/radiation etc)?

EDIT:

https://en.wikipedia.org/wiki/Neutron_star

The neutron star's gravity accelerates infalling matter to tremendous speed. The force of its impact would likely destroy the object's component atoms, rendering all the matter identical, in most respects, to the rest of the neutron star.

The escape velocity of a Neutron star is comparable to a black hole, so something like 1/2 of the speed of light.

So a 10 gram pebble hitting a Neutron star releases about the same energy as a 100 ton asteroid hitting Jupiter.

Does something like that burn up in whatever Jupiter's atmosphere is?

Are we seeing the flash of it burning up? or?

What impact would something which was 20ft in diameter do to the earth?

> As a rule-of-thumb, asteroids hit at or above escape velocity

At first I was like what the fish but with just a lil bit of thought you realize how intuitive this is. Pretty cool.

Objects move pretty fast in space, usually tens of kilometers per second. A 20 meter of diameter object with velocity of 10000 mps is pretty deadly impact from Earth's point of view.

Not really, the https://en.wikipedia.org/wiki/Chelyabinsk_meteor was 20 meter diameter and hit the atmosphere at about 20 km/s. While there were some ~1500 injured people, the Earth as a whole did not really notice.

How much does the angle of impact come into play?

From your link:

400-500 kilotons of TNT

I don’t know about you but I’d consider a Hiroshima-scale explosion pretty deadly. We just got lucky it didn’t hit the middle of a major population centre at a more direct angle. That could have been catastrophic.

It would suck to be in the area, yes. But the comment I was responding to said "pretty deadly impact from Earth's point of view." Hiroshima-scale explosions don't make an appreciable dent in the Earth itself, and any human population outside immediate vicinity will still be fine.

I wondered the same thing. 20 meters is about ~65 feet, just a little bit longer than a standard semi truck and trailer you might see out on the highway that’s hauling say, groceries. So my first thought was, “what kind of material would be that combustible to impact something at Jupiter’s size and leave that big a flash lasting 2 whole seconds?”

Someone else commented about the size of the flash relative to Jupiter itself and my understanding of that persons comment was that the flash was about 10 times the diameter of the object give or take a little. So 20 meters made a ~200 meter visible explosion.

Now somebody correct me if I’m wrong here since I most likely am, but isn’t Jupiter a gas giant? Meaning what we saw either detonated before hitting the surface, or what we saw was only the light from the impact explosion that made it through the gas/atmosphere layer above it at the point of impact. If the latter, the actual visible yield would have been higher than what we saw, right?

In order to be visible, the flash must have happened above the top cloud layer. The surface is well below that - Jupiter is mostly atmosphere, with a little bit of extremely compressed planet in its middle.

"Combustible" doesn't matter. Nor, really, does "impact" in the sense of one objectively solid body striking another objectively solid body. Think Chelyabinsk - the actual "thing hitting the ground" impact was a relative nothingburger, and all of the excitement happened at altitude.

> Meaning what we saw either detonated before hitting the surface

Since last I heard the understanding waa Jupiter probably does not have a solid surface to hit at all, “before” should probably be “without”.

I’m confused, what does the “(ft)” mean? Did they just forget to put a number there?

Fused Tachyons.

Looks like the proto-molecule finally found the Milky Way.

Is this a The Expanse reference or did that name come from somewhere else? (I ask because I don't remember hearing that the proto-molecule came from outside the Milky Way)

Was just thinking about that, will we see the ring forming?

Buried deep inside the article:

> Based on the images and video provided observers, the object’s diameter is estimated at 20 meters (ft). Similar to what happened with [the 1994 impact of the comet Shoemaker-Levy 9], this object is believed to be the remnant of a larger comet or asteroid that was captured by Jupiter’s gravity that broke up shortly before the impact took place.

I don't know what "20 meters (ft)" means. Probably a typo?

Right? Besides that, considering Shoemaker-Levy was a 6 million megaton impact (according do wikipedia), saying this was "similar" is just very wrong. Still interesting and pretty cool to have been caught on camera though.

The 'Similar' is in relation to how Shoemaker-Levy was broken up by Jupiter's gravity, and that this object comes from a similar process.

Ah, you're right, i interpreted that comparison wrongly. In that sense then it's most probably right. Still, we don't have any evidence that this impact was from a comet, it was most likely just an asteroid plunging into it.

I bet the author planned to fill in the number of feet later, and then forgot to.

Alien-lifeform-infested Eros?

Wouldn't that require us to already have a casino there?

Sasa nat ke Belta, Inyalowda?

No this is closer to SCP-2399[1] It even happened while being observed...

1. https://scp-wiki.wikidot.com/scp-2399

I'd wish

It gives latitude and longitude numbers, bit how do they work? Latitude makes sense but longitude on earth is in relation to an arbitrary line that goes through roughly where I'm sitting.

But I don't have a house on Jupiter, so what's it relative to?

Best I can tell, it's not as simple as declaring a Jupiter version of Greenwich through which to draw that line. Not all parts of Jupiter rotate at the same rate. Anyway, there are three coordinate systems, and given that I'm not the one to be explaining such things, I'll just leave the PDF link here:

https://lasp.colorado.edu/home/mop/files/2015/02/CoOrd_syste...

This was found by an amateur astronomer in Brazil, who was taking pictures of Jupiter to see Io's shadow on the planet.

"Big" is a very soft word to use in astronomy

it's all relative

Astronomy calls the largest non-structure objects dwarfs. It has no place to complain.

The size of that flash was about as large as the jovian moon.

I don't think my brain can fully comprehend Jupiter's size though. Reading about its size is one thing - bit forming that clear scale is nigh impossible for me.

Any chance NASA's Juno probe could have taken close-ups?

What would be the result if something this large hit Earth?

> Based on the images and video provided observers, the object’s diameter is estimated at 20 meters

The Chelyabinsk meteor was 20m and it damaged 7,200 buildings, it collapsed a factory roof and shattered windows (I have no idea the composition of either of both meteors but at least this gives some perspective):

https://en.m.wikipedia.org/wiki/Chelyabinsk_meteor

Chelyabinsk was 20m? That's surprisingly little damage for something equivalent to a massive light seen on Jupiter.

Chelyabinsk's light was probably similarly visible on Jupiter. The size of the light probably indicates the area illuminated by the explosion rather than the size of the explosion itself.

It was about as big as the https://en.wikipedia.org/wiki/Chelyabinsk_meteor from 2013, so "extensive ground damage over an irregular elliptical area around a hundred kilometres wide, and a few tens of kilometres long". So you would have a bad day if it hit the specific part of the Earth where you were located but overall not much would happen.

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