Speed

I thought the modeled Doppler notch velocity was 140 km/h. It was in FC2, or at least, that's what everyone told me.

I think we're interpreting Cali's post in opposite ways. To me, after I said it would be impossible for a 10 ton asteroid to cause this, he said "nothing's impossible". So I did the quick calculation I referred to.

Yea, when I am so badly taken out of context :D

Well, I would disagree... from very the beginning, it was pretty clear that the explosion had to have carried well in excess of 25 kilotons explosive power. 25 kilotons = 2.5e4*4.2e9 J = 1.05e14 J. Just using 1.05e14 = (1e4)*v^2/2, you can see that a 10 metric ton asteroid (m = 1e4 kg) would have to be travelling at 145 km/s- an impossibly fast speed- to deliver just 25 kt of explosive power (besides, the video clearly showed it was going much slower than that). At typical entry velocities (15 km/s) a 10 metric ton asteroid only carries like a quarter kiloton TNT explosive power.

Psstt.... Both of these issues are solvable if you use the debriefing module or other main simulation Lua environment modification methods I had mentioned- if you're interested in trying to solve them, maybe send me a PM sometime after I get SlmodStats finished and I have a bit more free time.

Great work!

Yea, I tend to think that whoever said 10 tons was either misquoted, misspoke, or was not an actual scientist... a simple calculation can show that it is impossible for a 10 ton asteroid to cause an event like this.

It's "official" now- this was the largest known asteroid airburst since the 1908 Tunguska event: http://www.space.com/19822-russian-fireball-biggest-explosion-century.html The scientist in this article estimates a diameter of 15 meters, a mass of 7000 tons, and an energy of 300 kilotons of TNT - about 20 "Hiroshima bombs". The above article also gives an estimated airburst altitude of 15-20km, and estimated of velocity of 18km/s - within the 10 km/s to 20 km/s velocities that are typical for these objects. Anyway... I really wouldn't be surprised if there was something larger since 1908 and now. The nuclear monitoring satellites supposedly see a lot of these explosions out over the water or in otherwise uninhabited areas, but I think that much of the data is still classified.

NNNNNNNNNNOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO...........

Why would you think it more likely to have been caused by a direct meteor strike than just something being knocked over? In fact, a meteorite would almost certainly not have caused that. After slowing down to under a few mach or so, they begin to cool rapidly as they fall through the, like, -40 degrees C lower atmosphere. By the time the reach the ground, they may be freezing cold. However, it's possible, for something that breaks up very low, for it to reach the ground at still a fairly high temperature. It is not likely though. So in conclusion, 99.9999% chance that was just something hot being knocked over, or something flammable being knocked into a fire, etc. ESPECIALLY in a place like a brick factory ;)

Looks like there were, in fact, a few pieces that made it to the ground. http://www.rosbalt.ru/federal/2013/02/15/1094880.html This has not been confirmed yet, but it seems reasonable that a few decent-sized chunks could have survived the explosion. According to the article, they should already be analyzing it. Hopefully the Russian authorities allow more access to the scene soon.

Depends on what unit attributes are assigned to it. Regardless... that's a ways away. Probably, I should manually re-assign P-51D (and, if applicable, the FW-190) to the "fighter" category- right now, ED classes the P-51 as an attack aircraft like the A-10 or Su-25. I put all multirole fighters in the "Fighters" category though, so definitely, the P-51 would fit better there. Also, maybe I should class the P-51D (and possible future FW-190) somewhere between the helicopters and attack aircraft in the PvP scoring system. Hmm... Edit: Added "Support and Recon" category to planes; "Unarmed Aircraft" changed to "Transports"; P-51D moved to "Fighters". I think that's good enough for now with that, now I am starting on the display interface, I'll show some screenshots when it becomes operational. Edit 2: Oh yea almost forgot- I wanted to improve the records kept for friendly fire. For team kills and team hits, the following information is now kept (in separate tables): [<hit or kill index number>] = { time = <number, Unix time (seconds since Jan 1, 1970)>, human = <string UCID, if applicable>, objCat = <string, general object type, like vehicle, ship, plane, static, helicopter>, objTypeName = <string, type name of the object>, weapon = <string, type name of weapon> } NOW, I think I'm finally ready to create the display system.

I doubt the 30 km/s number is accurate- 10-20 km/s is more typical. I suppose 30 km/s might be possible (I don't know what the MAXIMUM speed can be, but I'm pretty sure it CAN be higher than 30 km/s - the maximum possible velocity would probably be the escape velocity of the solar system at 1AU + the velocity of Earth around the Sun), but it's likely we'll see this number revised downward. From what I've read, the orbits weren't even close, as they shouldn't be.

No, asteroids don't "drag" anything with them, unless they happen to have a moon. And Apophis is far too small to have a moon- any such moon would quickly be tidally disrupted and float away. First of all, gravity doesn't work that way (in space, there is no friction, and momentum must be conserved, so gravity tends to make objects curve around them, not be sucked into them), and secondly, the gravity of these objects is FAR FAR FAR too weak to really do much of anything at all. We're talking escape velocities of like, a few centimeters per second, at least for the little guys like Apophis. Basically, the gravity of these little objects is far too low to hold onto anything, or influence anything whatsoever, or have any objects associated with them whatsoever. They lead solitary lives. Like I said, the bigger asteroids can hold onto a moon or maybe two (but I am not personally aware of any triple asteroids myself) but that's it. What can happen is that a planet's gravity can be strong enough that the tidal forces as the object approaches the planet will be strong enough to rip a loosely held "rubble pile" asteroid apart into little pieces. The little pieces will share similar orbits (assuming the object misses the planet) but eventually drift so that they are very far apart. And this object also had nothing to do with today's pass of 2012 DA14. It's just an amazing coincidence.

Well, it sounds like this thing didn't explode in the upper atmosphere... sound more like the lower atmosphere. And secondly, even a rocky (or iron!) object will explode unless its bigger than something like 10-100 meters across (depending on the structural integrity of the object). Imagine an asteroid plowing through Earth's atmosphere at 15 kilometers a SECOND. What happens is you get a TREMENDOUS pressure building up on the leading side of the object, and a near total vacuum on the trailing side. The total amount of force on the object is proportional to surface area, and structural integrity is more proportional to volume- so bigger objects suffer less than smaller objects. For smaller objects, even stony or iron asteroids, what happens is that eventually, the pressure builds so high that the object begins to break up. Since the new, smaller pieces are even more subject to this atmospheric entry pressure, they too break up. What you get is a runaway process where in a very short time, the asteroid disintegrates, releasing all of its kinetic energy in one short burst of superheated air.

Yes, those reports are rubbish. Russian SAMs are good, but they are not THAT good. :D

I might be fun to imagine such a huge object, but thankfully, none of the asteroids THAT size have a chance of impacting Earth, so videos like this will always just be fantasy. The biggest potential Earth impactor that I'm aware is 433 Eros, which is like 50 km across (correction- 30 km). That would definitely wipe out humanity, but the last I heard, it's pretty much guaranteed not to hit Earth in the next million years.

I'm not sure if you're implying this or not, but the smoke the object left behind is not a contrail- it's vaporized space rock. I'm sure some of that includes a bit of water, but I would imagine it's largely silicate and metal particles. You'll see them at any altitude. I watched the smoke trails/ionized air trails left behind from the brighter Leonid meteors during the 2001 Leonid meteor storm with binoculars- and those were probably all higher than 60 km up, maybe 100 km or so. They would last for like a minute, and it was cool watching winds in the upper atmosphere distort them into all sorts of weird shapes before they faded out. Oh and I wish people would stop calling this a meteor shower... meteor showers are harmless events where a cloud of sand-sized and MAYBE pebble-sized meteroids from a common parent body burn up in the atmosphere.

No, the fireballs in movies are never bright enough, and they always travel too slowly, at least in the movies I've seen. Imagine what a bigger asteroid would look like... this object was maybe 5-10 meters across and it was probably nearly as bright as the Sun or even brighter (it's hard to tell from the videos). Imagine what an asteroid 10000 meters across would look like as it approached the ground- everything line of sight to its fireball would probably flash into flame, maybe even into incandescent vapor. I do remember reading an account by a person who witnessed the 1908 Tunguska event fireball who said that it was so bright that the heat radiation coming off it was unbearable. Anyway, at least it's a good day for glass sellers... :lol: Hopefully, this event and the passage of 2012 DA14 will spur governments into more funding for asteroid survey telescopes and research into deflection strategies.

No, sound speed (air, sea level) = 343 m/s. 30*343 = 10290m = 10.29km However, sound speed is reduced at higher altitudes, so a 30 second delay could mean distances even less than that.... perhaps 9.5km or so.

I'm referring to that I hope no one was hit by any rocky debris that managed to survive the airburst. Often some small pieces will survive, and make it to the ground. They won't be traveling at orbital velocity, maybe not even supersonically anymore, but they will be traveling fast enough to kill you if they hit you.

LOL this needs to be a late addendum to Driving in Russia. Nearly getting taken out by a giant space rock would be icing on the cake... I mean, Russia is where all the asteroids hit isn't it? 1908, 2013...

4ZxXYscmgRg#! That's definitely a large bollide (extremely bright meteor). As an amateur astronomer, I've seen several bollides myself... but never anything even REMOTELY approaching that. The "best" one I saw was *only* as bright as the full moon (maybe a few times brighter, hard to judge really), crossed the sky in about 10 seconds, and made a few faint sonic booms audible a few minutes later. It was a wonderous experience, but... if I saw THAT ^^ coming at me... I'd be terrified. It looks like some big pieces may have survived the air burst at ~0:20-0:21. Hopefully no one was hit.

HOLY CRAP! That was one heck of a sonic boom. I imagine other videos will eventually surface that show the object during entry. http://www.space.com/19801-possible-meteor-blast-russia.html And this comes the same day as the closest recorded pass of a hazardous asteroid in history. http://www.space.com/19646-asteroid-2012-da14-earth-flyby-complete-coverage.html (We mentioned this object last year in this forum, http://forums.eagle.ru/showthread.php?t=86030 ) What an incredible coincidence.

Rather than simply "plane", "helicopter", "vehicle", "static", and "ship", I'm now using the following unit categories for stats tracking. With a few exceptions (like having to manaully move UH-1H and SH-60B from "Attack" to "Utility":huh:), the table below is automatically generated based on unit attributes. slmod.unitCategories = { ["Buildings"] = { ["Static Objects"] = { ["Subsidiary structure G"] = true, ["FARP CP Blindage"] = true, ["Subsidiary structure C"] = true, ["Barracks 2"] = true, ["Small house 2C"] = true, ["Military staff"] = true, ["Oil platform"] = true, ["Tech hangar A"] = true, ["Oil derrick"] = true, ["Tech combine"] = true, ["Coach a passenger"] = true, ["Airshow_Crowd"] = true, ["Hangar A"] = true, ["Repair workshop"] = true, ["Subsidiary structure 2"] = true, ["FARP Ammo Dump Coating"] = true, ["Small house 1C area"] = true, ["Subsidiary structure 3"] = true, ["Boiler-house A"] = true, ["Workshop A"] = true, ["Small werehouse 1"] = true, ["Garage small B"] = true, ["Small werehouse 4"] = true, ["Shop"] = true, ["Subsidiary structure B"] = true, ["FARP Fuel Depot"] = true, ["Coach cargo"] = true, ["Electric power box"] = true, ["Small house 1A"] = true, ["Container red 3"] = true, ["Garage A"] = true, ["Hangar B"] = true, ["Cafe"] = true, ["Restaurant 1"] = true, ["Subsidiary structure A"] = true, ["Container white"] = true, ["Warehouse"] = true, ["Shelter"] = true, ["Railway crossing B"] = true, ["Subsidiary structure F"] = true, ["Farm A"] = true, ["Fuel tank"] = true, [".Command Center"] = true, ["Coach a tank"] = true, ["Container brown"] = true, ["Supermarket A"] = true, ["Coach a platform"] = true, ["Garage small A"] = true, ["TV tower"] = true, ["Farm B"] = true, ["Subsidiary structure 1"] = true, ["Container red 2"] = true, ["Transport"] = true, ["Electric locomotive"] = true, ["Container red 1"] = true, ["Bridge"] = true, [".Ammunition depot"] = true, ["Small werehouse 2"] = true, ["Small house 1A area"] = true, ["FARP Tent"] = true, ["Water tower A"] = true, ["Locomotive"] = true, ["Shelter B"] = true, ["Pump station"] = true, ["Comms tower M"] = true, ["Coach cargo open"] = true, ["Tank"] = true, ["Landmine"] = true, ["Building"] = true, ["Railway crossing A"] = true, ["Subsidiary structure D"] = true, ["GeneratorF"] = true, ["Small house 1B area"] = true, ["Small werehouse 3"] = true, ["WC"] = true, ["Small house 1B"] = true, ["Garage B"] = true, ["Chemical tank A"] = true, ["Train"] = true, ["Airshow_Cone"] = true, ["Subsidiary structure E"] = true, ["Railway station"] = true, }, -- end of ["Static Objects"] }, -- end of ["Buildings"] ["Ships"] = { ["Unarmed Ships"] = { ["ELNYA"] = true, ["Dry-cargo ship-1"] = true, ["SOM"] = true, ["ZWEZDNY"] = true, ["KILO"] = true, ["Dry-cargo ship-2"] = true, }, -- end of ["Unarmed Ships"] ["Other Ships"] = { ["speedboat"] = true, }, -- end of ["Other Ships"] ["Surface Warships"] = { ["REZKY"] = true, ["PERRY"] = true, ["TICONDEROG"] = true, ["MOSCOW"] = true, ["NEUSTRASH"] = true, ["PIOTR"] = true, ["KUZNECOW"] = true, ["ALBATROS"] = true, ["VINSON"] = true, ["MOLNIYA"] = true, }, -- end of ["Surface Warships"] }, -- end of ["Ships"] ["Planes"] = { ["UAVs"] = { ["MQ-1A Predator"] = true, }, -- end of ["UAVs"] ["Fighters"] = { ["MiG-23MLD"] = true, ["F-14A"] = true, ["Su-30"] = true, ["F-16A"] = true, ["Mirage 2000-5"] = true, ["MiG-29G"] = true, ["Su-27"] = true, ["MiG-25PD"] = true, ["F-16C bl.52d"] = true, ["MiG-29K"] = true, ["MiG-31"] = true, ["F/A-18C"] = true, ["F-15C"] = true, ["F-16A MLU"] = true, ["F-16C bl.50"] = true, ["F/A-18A"] = true, ["MiG-29S"] = true, ["F-15E"] = true, ["Su-33"] = true, ["MiG-29A"] = true, ["F-4E"] = true, ["F-5E"] = true, }, -- end of ["Fighters"] ["Bombers"] = { ["MiG-27K"] = true, ["Tu-95MS"] = true, ["B-1B"] = true, ["B-52H"] = true, ["F-117A"] = true, ["Su-17M4"] = true, ["Su-24M"] = true, ["Tu-22M3"] = true, ["F-111F"] = true, ["Tornado IDS"] = true, ["Tornado GR4"] = true, ["Su-34"] = true, ["Tu-160"] = true, ["Tu-142"] = true, }, -- end of ["Bombers"] ["Unarmed Aircraft"] = { ["IL-78M"] = true, ["E-3A"] = true, ["E-2D"] = true, ["An-26B"] = true, ["MiG-25RBT"] = true, ["C-17A"] = true, ["An-30M"] = true, ["S-3B Tanker"] = true, ["A-50"] = true, ["S-3B"] = true, ["IL-76MD"] = true, ["Su-24MR"] = true, ["KC-135"] = true, ["Yak-40"] = true, ["C-130"] = true, }, -- end of ["Unarmed Aircraft"] ["Attack"] = { ["Su-25T"] = true, ["Su-25TM"] = true, ["Su-25"] = true, ["A-10C"] = true, ["A-10A"] = true, ["P-51D"] = true, ["L-39ZA"] = true, }, -- end of ["Attack"] }, -- end of ["Planes"] ["Ground Units"] = { ["Artillery"] = { ["Smerch"] = true, ["SAU Gvozdika"] = true, ["Grad-URAL"] = true, ["MLRS"] = true, ["SAU Msta"] = true, ["2B11 mortar"] = true, ["SAU 2-C9"] = true, ["SAU Akatsia"] = true, ["M-109"] = true, }, -- end of ["Artillery"] ["SAM"] = { ["S-300PS 54K6 cp"] = true, ["Patriot ln"] = true, ["Stinger manpad dsr"] = true, ["SA-11 Buk CC 9S470M1"] = true, ["M6 Linebacker"] = true, ["S-300PS 5P85D ln"] = true, ["snr s-125 tr"] = true, ["S-300PS 40B6M tr"] = true, ["Kub 1S91 str"] = true, ["p-19 s-125 sr"] = true, ["M1097 Avenger"] = true, ["S-300PS 5P85C ln"] = true, ["S-300PS 64H6E sr"] = true, ["Kub 2P25 ln"] = true, ["SA-11 Buk LN 9A310M1"] = true, ["Patriot ECS"] = true, ["5p73 s-125 ln"] = true, ["Patriot AMG"] = true, ["SA-18 Igla-S manpad"] = true, ["SA-18 Igla manpad"] = true, ["Roland ADS"] = true, ["S-300PS 40B6MD sr"] = true, ["Hawk ln"] = true, ["Hawk sr"] = true, ["Strela-1 9P31"] = true, ["2S6 Tunguska"] = true, ["Patriot str"] = true, ["SA-11 Buk SR 9S18M1"] = true, ["Patriot cp"] = true, ["Tor 9A331"] = true, ["Strela-10M3"] = true, ["M48 Chaparral"] = true, ["Stinger manpad"] = true, ["Hawk tr"] = true, ["Patriot EPP"] = true, ["Osa 9A33 ln"] = true, }, -- end of ["SAM"] ["Unarmored"] = { ["UAZ-469"] = true, ["LAZ Bus"] = true, ["SA-8 Osa LD 9T217"] = true, ["IKARUS Bus"] = true, ["Predator GCS"] = true, ["GAZ-3308"] = true, ["SKP-11"] = true, ["ATMZ-5"] = true, ["GAZ-3307"] = true, ["VAZ Car"] = true, ["ATZ-10"] = true, ["Ural-375 APA-50"] = true, ["Ural-375 PBU"] = true, ["MAZ-6303"] = true, ["Ural-4320T"] = true, ["Ural-4320-31"] = true, ["M978 HEMTT Tanker"] = true, ["ZIL-4331"] = true, ["KAMAZ Truck"] = true, ["GAZ-66"] = true, ["ZIL-131 KUNG"] = true, ["Predator TrojanSpirit"] = true, ["M 818"] = true, ["ZiL-131 APA-80"] = true, ["Ural ATsP-6"] = true, ["HEMTT TFFT"] = true, ["Suidae"] = true, ["Ural-375"] = true, ["Trolley bus"] = true, }, -- end of ["Unarmored"] ["IFVs"] = { ["BMD-1"] = true, ["M1134 Stryker ATGM"] = true, ["M-2 Bradley"] = true, ["BMP-3"] = true, ["BMP-1"] = true, ["Marder"] = true, ["BMP-2"] = true, }, -- end of ["IFVs"] ["AAA"] = { ["ZSU-23-4 Shilka"] = true, ["ZU-23 Closed Insurgent"] = true, ["Gepard"] = true, ["ZU-23 Emplacement"] = true, ["ZU-23 Emplacement Closed"] = true, ["ZU-23 Insurgent"] = true, ["Ural-375 ZU-23 Insurgent"] = true, ["Ural-375 ZU-23"] = true, ["Vulcan"] = true, }, -- end of ["AAA"] ["Other Ground Units"] = { }, -- end of ["Other Ground Units"] ["EWR"] = { ["1L13 EWR"] = true, ["55G6 EWR"] = true, ["Roland Radar"] = true, ["Dog Ear radar"] = true, }, -- end of ["EWR"] ["Fortifications"] = { ["house1arm"] = true, ["houseA_arm"] = true, ["Sandbox"] = true, ["Bunker"] = true, ["outpost"] = true, ["outpost_road"] = true, ["house2arm"] = true, }, -- end of ["Fortifications"] ["APCs"] = { ["M1043 HMMWV Armament"] = true, ["BTR_D"] = true, ["Boman"] = true, ["BTR-80"] = true, ["MTLB"] = true, ["M1045 HMMWV TOW"] = true, ["AAV7"] = true, ["MCV-80"] = true, ["BRDM-2"] = true, ["LAV-25"] = true, ["M-113"] = true, ["TPZ"] = true, ["Hummer"] = true, ["M1126 Stryker ICV"] = true, }, -- end of ["APCs"] ["Tanks"] = { ["M-60"] = true, ["T-55"] = true, ["Leopard1A3"] = true, ["Leopard-2"] = true, ["M-1 Abrams"] = true, ["Leclerc"] = true, ["T-80UD"] = true, ["T-90"] = true, ["Challenger2"] = true, ["M1128 Stryker MGS"] = true, ["T-72B"] = true, }, -- end of ["Tanks"] ["Infantry"] = { ["Soldier M4"] = true, ["Soldier M249"] = true, ["Infantry AK"] = true, ["Soldier AK"] = true, ["SA-18 Igla comm"] = true, ["Soldier RPG"] = true, ["Paratrooper AKS-74"] = true, ["SA-18 Igla-S comm"] = true, ["Paratrooper RPG-16"] = true, ["Stinger comm dsr"] = true, ["Stinger comm"] = true, }, -- end of ["Infantry"] }, -- end of ["Ground Units"] ["Helicopters"] = { ["Utility"] = { ["CH-47D"] = true, ["SH-3W"] = true, ["Mi-26"] = true, ["Ka-27"] = true, ["UH-60A"] = true, ["SH-60B"] = true, ["CH-53E"] = true, ["Mi-8MT"] = true, ["UH-1H"] = true, }, -- end of ["Utility"] ["Attack"] = { ["AH-64D"] = true, ["Ka-52"] = true, ["OH-58D"] = true, ["Mi-28N"] = true, ["Ka-50"] = true, ["AH-64A"] = true, ["AH-1W"] = true, ["Mi-24V"] = true, }, -- end of ["Attack"] }, -- end of ["Helicopters"] } -- end of slmod.unitCategories What other categories might be needed? Planes.Support?