UNITED STATES ATOMIC ENERGY COMMISSION LOS ALAM □ 3, NEW MEXICO ADDRESS REPLY TO: MANAGER, SANTA FE DIRECTED OPERATIONS U. S. ATOMIC ENERGY COMMISSION P. 0. BOX 1519 LOS ALAMOS. NEW MEXICO AND REFER TO: uPD ^o"! liar ch 22, 1949 Lt. Gindr. Richard Blondo Ik or n AFSI7P Headquarters Sandia Base Albuquerque, Hew Hexico Dear Cmdr. "andelkorn; Furnished herewith is a transcript of the minutes of the conference held at Los Alamos February 1G, 1949, pertaining to aerial phenomena. R & D I in nr R O U TIN G CiR6 TOR — ■■ ~ -== INI HALS DEPUTY — --- EXECUTIVE -------— — ------------------ — — — adm in — — --— — — — ------------------—t SUSPENSE ----------------- FILE ______ ^-7 — -------1 Very truly yours. Sidney 1 ewbu/gcr, Jr. Chief, Security Operations Branch Encl: As indicated "When separated fren er.closures, handle this —----------- ■ d ec lassified ...en t# in , i;. j rvb lU ited „ .u ^ । itn H 1'?^ u o d rr CONFERENCE On AERIAL PBEKCMSKA Held at 1300; 16 February 19^9, ^ conference room P-162, Los Alamos Scientific Laboratory, Loa Alamos, Nev Mexico. Present: Uth Army: Major Winn Major Godsee Captain Reef AFSWP: Commander Hundelkorn University of Hew Mexico: Dr. LaPaz FBI: Mr. Maxwell USABC, SFOO: Mr. Morgan Mr. Hewburger University of California: Dr. Bradbury Dr. Holloway Mr. Hoyt Dr. Henley Dr. Heines Dr. Teller Mr. Hewburger opened the conference end stated that the subject of Aerial Phenomena was classified Secret within the meaning of AR 380-5 and comparable appropriate regulations of the Navy and Air Forces, and that all personnel at this meeting were properly cleared. Mr. Hewburger then introduced Captain Beef, who briefly outlined the purpose of thia meeting. Captain Beef: It all started back In December, 19^8, when w first received some reports from some airline pilots that these green fireballs were sighted. At this stage we had no idea what to do with it or what it was. We approached Dr. LaPaz who has been assisting us, gratis, since that date. Almost over two sionths now that he has been assisting us, so in order to have you get the facts as they are to a scientist, I’ll let Dr. LaPaz explain these things as we have * found them. Thea you can give us your opinion from there; that is what we are interested in. Dr. LaPaz: I would like to review what is observed in the ease of a conven­ tional meteorite fall. Hot that I have any hopes of saying anything you don’t already know, but because I regard the observational evidence observed by the conventional meteorite falls as providing ths necessary background for that is now observed. Meteorite falls (for next minute or two, Dr. LaPaz’s caanents on record drowned out by noise from ditch digger immediately outside conference room) ....... Because of sound phenomena primarily, the fall of a large meteorite will cause great fright among human beings necessarily but primarily among animals, of all kinds- The fact follows, by a meteorite falling into the D EC LA SSIFIED -. fc& ttfly A z/b ~3? 7 3 jiiO R T Conference on AERIAL PHENOMENA Page 2 earth., is as you would, expect, one at random - in azimuth and. elevation. If the radiant ■white is known, you can predict the minimum angle with respect to the plane of the horizon at which the meteorite path has been observed. There is no choice, as far as the ..... for direction when meteorites fall in at random. I’d like to contrast now, at this time, this fact with what has been observed by some individuals here at the conference and by many of the AESS inspectors, UAL pilots, special agents, goodness knows how many other categories of people. I choose to describe the only one of the incidents that I was personally a witness to. It is the only one of the incidents that I am in a position to vouch for on the basis of experience, dating from 1915, as a member of the American Meteor Society, was most certainly not a conventional meteorite fall. It was the so-called Starvation Peak incident on the night of December 12 191*3. Tine of observation around 9 >02 F-M., plus or minus 30 seconds. This fireball appeared in full intensity instantly - there was no increase in light. Its color, estimated to be somewhere around wave length 5200 engstroms, was a hue green, or yellow green, such as I had never observed in meteor falls before. The path was as nearly horizontal as one could determine by visual observation. We have a photograph which might be some liters of departure from horizontal. The trajectory was traverse at, I am inclined to believe, constant angular velocity. Just before the end of the path there was the very slightest drooping of the path, that is the green fireball broke into fragments, still bright green Dr. Teller; And all this time the intensity was approximately constant? Dr. LaPaz: All the time, as far as I could determine. The eye, of course, is admittedly a very crude photographer. Dr. Teller: How long did the phenomenon last? Dr. LaPaz: Almost exactly two seconds. We have in the reports here, I brought the complete file with me and would be glad to circulate them, duration measures in relation to all observations. Few of these, however, I believe, were determined under as favorable circumstances as the duration of the Starvation Peak incident. Possibly I should go back and review the situation a little bit. Because some report, issued by the AESS, would certainly suggest that I was primarily responsible for starting this whole matter I am glad that Captain Reef corrected that impression. Actually, I was on an investigation in regard to the green fireball observed on the night of December 5th at the time the December 12th incident occurred. As a result I was keyed up; I was watching; I hud a stop watch with me and a transit. We got into position and made measures, transit measures, on azimuths and elevation readings; that is, we made a duration check, certainly within not more than two or three minutes after the incident occurred. To that extent, I believe, it is possibly the best observed of any incident up to the time of the January 30th fall. Dr. Manley: How did you have time to use the transit? Dr. Lapaz: The transit was in the back of the car. The moment the car was parked at the side of the road, we yanked the transit out and set it up and Conference on AERIAL PHENOMENA Page 3 began measurements. We were in motion at the time but we were able to get a very good, check of what we observed at the time on the road near Starvation Peak. Ue had a clear view of the sky to the Worthwest and the West, and the object wan so low over the horizon it was possible to compare it not only to the stag’s with which I am familiar, but with respect to mountain peaks ‘that were also visible. To continue, that duration was about two seconds. This is one of the puzzling things to the meteorists. I believe I do not exaggerate when I say that 90$ of the duration determinations that have been made in the case of tiie green fireballs have given durations right in that vicinity. Whereas you take, say, 100 ordinary meteor observations you will find the widest diversions in durations. You could take the same lesson as observed by 100 people - possibly that’s a better example - and there would be wide variations in the estimates of duration. Dr. Mauley: Did you correlate the azimuths with.... ? Dr. LaPaz: No. There is an azimuth factor here which I am going to talk to you about, that relates to the choice of direction. Both our observations are single station observations, so that it becomes impossible from the observa­ tion measure to determine the real path of the fireball in the atmosphere. There have been only three cases where that path was determinable. One, as I recall it, was that of December 12, another December 20, and finally, of course, the very large fall on January 30, 19^9- I’ll give you some particulars on the paths. I do want to observe, however, that even our station observations present a puzzling characteristic to the meteorists. If you plot what are called, by meteorists, the admissible protozons for a green fireball that has been observed, you will find that they give, on the average, an approach almost to the North, come down from the North, they are not restricted to ? . Now what about, the real paths? I gave seme Indications as to the altitude at which meteorites normally disrupt full ..... and come down. That relates to the lowest....of path. The green fireballs are unusual in this respect: probably that they are horizontal or nearly so, or that their horizontal path is traversed very low down in the atmosphere. In the case of the real paths for which we have been able to make determinations so far, those are graphical determinations, as we have not taken the trouble to use Chablis (?) methods or ..... because the observations sire regarded as necessarily too rough for mathematical niceties. Those paths are traversed at elevations between 8 and 10 miles. I defy you to find anywhere among meteorists, examples of conven­ tional meteorites that move over long horizontal paths reserving nearly constant angular velocities and therefore, on the average, constant linear velocities, at elevations of the order of 8 to 10 miles. There is a good deal of evidence that may be of value in the complete reports that are available hare, but since this is an introduction, I would like to summarize at this stage: the fireball which I personally witnessed on the night of December 12, 19^8, was not, in my opinion, a conventional meteor fall. Since the majority of the green fireballs have been reported to me, both before and after this December 12th occurrence, possess almost all the properties which I personally observed on the night of December 12th, I feel that in all probability they are not themselves conven­ tional meteor falls. Now, the easy way out of this is to conjure up an un­ conventional type of....meteorite, which comes in practically parallel to the Conference on AERIAL PHENOMENA Page 4 surface of the earth and is somehow endowed with the property against the very great atmospheric resistance that is experienced on a level, it reserves nearly constant velocity over paths say of the order of 25 to over 100 miles, as in the case of the green fireball on January 30th. It should also have the property that it is a very remarkable hue of green, not heretofore observed, to my knowledge, in the case of any conventional meteor falls. And finally, and this possibly is the most implausible feature of all, that although it produces light visible at distances of the order of 400 miles, it doesn’t make a sound. In the case of the January 30th fall, due to the fact that there had been a large number of military personnel alerted, we were able to obtain observations within a minute after the fall occurred and. pursued the investiga­ tion over a distance of 1,600 miles - in Texas mud primarily! - in some ten days’ time interviewing literally hundreds of people, we saw not one substan­ tiated account of noise produced by the meteorite fall.. Ur. Teller? May I ask how many people have seen this one big meteorite? Dr. LaPaz: That is difficult to say. (record blank for short period)....... Finally, in the Interrogation of such persons, we invariably interview them as Individuals. We triad a family of 8 the first night, as Major Godsoe will recall, interviewing ..... and it became apparent at once that there wan setae sympathetic influence and we broke it off after I think the third or fourth observation end thereafter interviewed separately. If you were to search, however, the independent observations of those who were widely separated, possibly si,ahiohb of the order of 100, there were probably 100 different stations reporting. Dr. Teller •. What area did that cover? Dr. LaPaz: All of New Mexico, all the Western half of Texas. I have a map here with cone indications of possibly the extent of that. Hoyt and Bradbury: Wasn’t that Sunday the 2bth? Dr. La?as: Ho, it was definitely Sunday the 30th. The newspapers have very helpfully concealed most of the relevant facts relating to this fireball. First, they described it as a fireball, second, they ....(record blank for few seconds), interferred with 0SI and wasn’t able to do that this time. This is the field leap and will give in various colors, dots end pencil daahs, etc. all of the observations obtained on the Texas search. Dr. Teller: All relate to one fall? Dr. LaPaz: Yes. These lines are drawn from points of observation. The center, as you see. of points of appearance is somewhere Southwest of Amarillo or South- southwest of Amarillo. The disappearance point is in the vicinity of Lubbock, Texas. At the time thia was drawn, before I was able to make out transit measures in the vicinity of Albuquerque, this was the best apparent path of the fireballs. These other ink lines ore independent, made by other groups of observers working on the same problem, (record blank again for short time). This transit, unfortunately, had a needle with a bent piston end it was not Conference on AERIAL PHESIOMEHA Page 5 discovered until much later that we were getting faulty records. Independently, I have re-determined, using the best equipment available at the University, the lines of sight at all points where the faulty transit had been used. I have plotted on this map only observations that I made personally or such observa­ tions as I have every reason to believe were made by experienced personnel, for example UAL flyers, who took tile trouble to make measures, or possibly civil engineer's. Dr. Teller: You mean these people right afterwards or shortly afterwards took an instrument and tried to measure it? Dr. LaPaz: That's right. Dr. Teller: This is the point where it disappeared? Dr. LaPaz: And normally, all you will get is the point where it disappears, because the average man. is aware of the fact that when he is not warned, he makes a very inaccurate observation. Having been warned by the appearance of the firebell, hie attention is fixed and he watches where it bursts, where it explodes, where it disappears* So I say this is a much better determination. This beginning point, although you notice the .... of line here, is reasonably satisfactory* Dr. Teller: Are these points here observers of the test, locations of those observations? Dr. Lapaz: Usually a dotted circle like that indicates a reported sound obser­ vation. We use this symbol: a circle is a report, whether or not the observation includes azimuth of elevation, light appearances, is indicated "y the presence of a cross. If it is blacked out, both light and sound were heard. How every one of those things has been disproved. In the area where the end point was located, oil well drilling was underway, dynamite blasting in connection with setting up of rigs, some nitro being used apparently to shatter.... In every case we ware able to exclude the possibility that the noises reported actually were tied in with the meteorite fall. At least let me say, in my opinion, those noises were excluded* In certain cases, independently, that was confirmed by a visit of Lt. Kyan of the Roswell group of the CSX. For instance, the best case of all, near Amherst ?, or noise - the observer, it s true, was only a tea-year old boy, but he wrote a very intelligent letter, and it is well known that children, like animals, are more sensitive to sound than people who have listened for too many years, say, to the radio. It appeared conceivable that he had actually made a sound observa­ tion, but Lt. Ryan went to Amherst ?, found that even three members of the family were not able to confirm his observation of noise and no one in the town, aa®e 300 or 400 persons I think in all were estimated to have been visited, no one at all had heard a sound, so I think that Mike probably heard the same dynamite blast as had been reported by Miss Winson Didpasture - I didn’t take that name out of the funny papers, it actually exists, (continual examination of the maps with minor interrogations concerning msrklngB.) Conference on AERIAL PHENOiflSJIA Page 6 Dr. LaPaz: With, one exception, in the case of Roswell, there are two types of sound associated with meteorite falls and, I assume, associated with the motion of any very high velocity projectile or missile through the air. There are what physicists would call reasonable sounds, and while he would not acknowledge it, simultaneously with the appearance of a meteorite, you hear a meteorite, the physicist rill refuse to believe the observation. Nevertheless, there is a tremendous volume of evidence indicating that these anomalous sounds occurred. Anyone who does field work in the search for meteorites rill cose across possibly lOjt of the observers who say that, although sy attention was attracted by hearing, a whining noise, a whistling noice. I looked up and there was the fireball. In other words, this anomalous sound apparently attracts attention to the occurrence. I have an article by Brandon....one of the sons of the man who first investigated the great crater out in Arizona, and a chap by the name of Hart ? with whom I am not personally acquainted but a physicist apparently at Princeton, in which they attempt to justify the occurrence of anomalous sound. They express it roughly in this fusion. Electromagnetic radiation is set up by (Dr. Teller excused to answer the phone.) Dr. LaPaz: You wouldn’t believe it anyway’ However, ....electromagnetic radiation io rectified somehow by the....changed into sound that can be heard and, therefore, you can hear the meteorite at the same time you see it fall. In the case of the Roswell observation apparently that occurred. We have a group of five men - there were near a steel smokestack - and every last one of them swears that they heard at the seme time they were watching the green fireball go by, a noise like, say, a gasoline blowtorch. That is certainly not an ordinary explosives sound. One more thing in connection with the noises. In every other meteorite fall, any one meteorite fall that I have investigated, - that covers many years • I have never yet found an occasion of a detonating fireball, without meteorites coming down at all, in which there was not some evidence of alarm of animals. Chickens will fly around to try to get under cover. Dogs will howl and try to get into the house. Horses will run away. In the case of the Texas fall, in spite of the tremendous urea in which the light was observed, we found not a single case in which the entasis were disturbed. We knew of the c^se of a farmer who had, in sunny Texas, a pond with a five-inch layer of ice, who reported that a meteorite had fallen through the ice on that pond, had broken a hole. Captain Neef here put on a pair of rubber boots and very thoroughly searched the pond without finding a meteorite. Even in that oase there was no evidence of alarm by the animals. I believe with that summary, I'd better cease operations and have you ask questions. Question: 3oir many observed falls? Dr. LaPaz: I'd like to classify those into three groups. I would say that there are ten instances that definitely merit the most serious consideration. They are strictly analogous to the green fireballs of the night of December 12. On top of that, there must be seise thing of the order of twenty more which are Conference on AERIAL PEEIOSA Page 7 so Mil reported, from Los Alamos for example, that although the green fire­ balls observed, shoved small .... the nature of the fireball .... many observations of observers who paid, practically no attention to the sky at any other time in their lives and now when they see a really bright light, they report it. You will find a great many instances of bluish-white fire­ balls. In my opinion, those falling vertically and leaving trails, are simply ordinary shooting stars. Of high intensity, that 1b, what we call fireballs, a blue light, are not in any sense to be associated with the green lights. Those three categories then. Dr. Manley: ? Dr. LaPaz: In the case of the two green fireball paths, determined from Lob Alamos observations, in one case the Starvation Peak incident, we have an East-West motion, and then also a motion exactly parallel to ..... In other words, these two real paths show, I think they are the only two of the first category that show any real departure from the.... It is possible to explain that. It is quite evident that we Ji&ve no case of assurance that both groups of observers, the observers at'starvation Peak and the observers at Los Alamos, saw the same point of....so that if We were to merely ask what are th© limits within which such real paths might fall, it turns out that it might be as short as 12 miles instead of being 25 miles long, and in that co.se it would be directed, almost directly to the Eorth; it would come down very nearly within 2 degrees, 5 degrees say, of the North. In the case of the Texas observations, whereas I have indicated and the maps show, we have many observations by trained observers, motion is clearly almost directly north to South. I have been informed that there are reasons for regarding the .... out here (ditch digger) ... and you notice that this passes reasonably close to Lubbock. The seme is true of the two earlier fireballs, those of December 12 and December 20. They both passed « one passed centrally over Los Alamos and the other about six miles Dorth of the center, but this would not be true.... (ditch digger). One point that possibly should have been mentioned earlier is this: I was the more Interested when Captain Heef came to my office and brought the December 5th incident to my mind because very much earlier I had been contacted first by ... White, Director of Texas Observers, in regard to their remarkable green flare seen on January 1, 19^8. Second, from a Dr. Pruitt, Director northwestern Section, City Section, of the Meteor Society, I had been informed that earlier occurrences of bright green fireballs, not too fax f?® the Hanford area. 'When Captain Heef came in with reports of green fireballs user Las Vegas and particularly when he disclosed that there was a Los Alamos near Las Vegas - the real Los Alamos - it had much interest. Dr. Holloway: Are there any reports of these from other installations, such as Troy, l?ew York, or places like that? Dr- LaPaz: I raised that question and I know of no other cases. I mean to say the areas from which these reports cose, as in one, for such evidence as ..... they do not relate to the green fireballs; they relate to the daylight occurrence of horizontal moving, bright white objects - some in Memphis, Tennessee in May, 19^-8 - that is not too far from Oak Ridge. They relate to Conference on AERIAL PHENOMENA Page 8 the Hanford area as far as the Pruitt observations go, and to the observations that I’ve mentioned here in the Lbb Vegas-Los Alamos area ...... A very curious tiling has come to light during these investigations. I published not long ago tin article in Science Illustrated on the recovery of the .<>.,. Town meteorite. The time that fell, February 18, 19^, the rumor got around scaaehow in Northern Kansas and Southern Kansas that it was a Russian bomb, and it was aimed at the geographical center of the Calved States which is not very far from . *... Apparently, a great many people gave credence to that rumor and were delighted when we finally recovered meteorites up there and proved it wasn’t anything but an ordinary meteorite fall. Incidentally, it did not have the character!sties of ths green fireball we’re talking about here. There was an air transport pilot who made a most curious observation while flying near Cherbourg an Jammy 16, 19^6. Hie observation was the observation of a bouncing meteor. After what I*ve been telling you about the green fire­ balls, you probably think it not unreasonable that a meteorite should bounce but to the meteorlytical mind that seems very hard to swallow. The interest is that one of your own persons here at Los Alamos, one and confirmed at least in part by four other persons, saw one of the green fireballs come down and then, glide off horizontally. The bouncing meteorite is manually explained by having it form, say sinusoidal motion lying in about the plane at which the observer was looking so that he first saw the high point of the curve or the peak. The next time it was at the peak, it was so far away that the altitude was very low, which will give you the appearance of a bouncing meteorite. I offer that as a possible explanation. Of course, he may have landed in Paris before he made the Cherbourg flight and then we should disregard the testimony entirely! Mr. Kewburger: Dr. LaPaz, you mentioned, I believe, at one of our other meetings that they had compared the color of this with certain metals? Dr. LaPaz: That’s right. Initially we could only ask them what they thought it looked like. And we got such interesting responses that we eventually carried around a spectrum chart and allowed everybody to make his own choice. Of course, the use of the spectrum chart was unnecessary if they have a color like one lady who had around her neck a green scarf which she assured me had exactly the same hue, but normally not having such things to lock at, they were pleased, to have the chart to look at. They will choose, in 90^ of the cases, category 1 and category 2 a wave length which corresponds to something between ^900 and possibly 5300 > Most of them will fall very close to 5 218 which is about the color you get when you have copper salts in the Bunsen burner. I checked with Dr. Regener on. that and asked him if an alloy had been used, like, say, copper beryllium, if there would be any change in that hue, sad he has assured me there would not. He said it would still give approximate appearance of beryllium copper....You will find in probably 1350 of the 1500 only the merest trace of copper occurrence. There are a few meteorites like.... in South Dakota, where little veins of copper have been found, making up possibly ,U of 1$. Dr. Bradbury: Is this true of all meteorites? Conference on AERIAL PHEWOMEKA Page 9 Dr. LaPazr It’s true in any category. Even in the irons, the presence of copper is very hard, to detect, very little.......(ditch digger). I don’t know whether you gentlemen could suggest an easy way to obtain green fireball spectra or not. Dr. Teller: What is the geographical solution of this? Dr. LaPaz; Another map would probably answer that best of all. (Looked at snore maps with seme talk that was not audible.) Mr. Hoyt confirmed the green hue of the green fireball he had seen on the night of December 30, 19W. (Record dead dor minute or two.) Mr. Hoyt: I would have said approximately as far above the mountain as the floor of the valley was below the top of the mountain. I felt that would give me somewhere in the neighborhood of 20,000 feet or thereabouts. It was about 5 minutes to 6, on my way up here. I have a feeling that it had a downward path. I mean it was going South. Dr. LaPaz: But it was not strictly horizontal? Mr. Hoyt: Ho. Dr. LaPaz: We have some discrepancies in that regard. 9% of the observa­ tions indicate a very nearly horizontal path. One from Fort Worth, Texas, which was not made by....but measured by them, indicates an elevation of 6 degrees at the beginning and 2^ to 3 degrees at the end. Mr. Hoyt: That’s what I would have said, but remember that the ridge would give you the sensation that it was taking a downward path. Duration - at the time I would say it was approximately 3 seconds. Comdr. Mardelkom: How does the calculated velocity of these objects compare with the known velocity of meteorites? Dr. LaPaz: Apparently very much lower; that is, more than the ordinarily observed meteorite falls. First, to observe in the cast of an actual meteorite fall you have a relation of the velocity from the auricle of.... atmosphere down to the impact velocity which may be very....but it isn’t fair to compare the velocity of the green fireballs to the impact velocity of..... (ditch digger and everyone talking at once)..... . Hot with the trajectory velocity of the meteorite which is the seme as the velocity of the fragments that fall from the meteorite. After a meteorite....the fragment a fall about like a bomb. Their resistance just about balances out the....and as a result, they come down with about the velocity of a falling bomb, a little less because they do not have the same ballistic coefficient. Dr. Bradbury: This is not an excluded ? direction like the.... ? Conference on AERIAL PHENOMENA Page 10 Dr. LaPass Due to the fact that they have a curve, and practically all times during which darknees is with ue, why they tend to come in from that direc­ tion. ... Dr. Bradbury: Would it be a ehewer? Dr. LaPaz: That was my first explanation, as a natter of fact. Geminate showers id.th a aaxisnEi of December 10 to December 12. The first evidence that I had war Sgt. Kinsley’s report on December 2 and since often the forerunners of the showers will....I thought we were talking about Geminate showers except that I never observed a green Geminate. Matter of fact, a check of observations made at that time found that there were 41k observations since 1915 and there wasn’t a single one, Geminate or non-Geminate, for which any hue of green was mentioned. Later, for instance on the night of December 12, you could watch the Geminate come down.... and notice that they case in at high angles to ths horizontal, whereas the green fireballs .... Incidentally, we have another interesting piece of evidence there - Dr. Sherman Smith from the University - I mention an observation that he made on the same night. The time of the observation is in dispute. According to Dr. Smith it was probably as late as 10:50. He had to wait for a long time, he said, for his wife to pick him up after the concert vas over. Mrs. Smith, however, times it around 10:10. Whatever the time, within an hour or say an hour and a half after the green fireball end the horizontal path were observed, we have another extremely bright blue firehell case out of the Geminate rays. I mention this because some of the first persons to concern themselves with this problem suggest that the green fireballs were simply abnormally bright Geminates. Apparently you can have very large Gaainate falls of the color estimated by a trained..... checked with the spectrum charts....is quite distant, I assure you, from the green fireballs. Comdr. Maidelkorn: How good is the coverage of the observers of the American Meteor Society as far as the top-half of the United States is concerned? Dr. LaPaz; It depends a good deal upon overcast conditions. I would say, however, that this year the Eastern half of the country has offered phenomenal observing conditions. One of my reasons for withdrawing from Ohio State ves that after 13 years there I had given up hope of ever seeing a meteorite shower because during the season cf maximum intensity of the falls we had heavy over­ cast, snow end so forth. On the other hand, this year they’re had reasonably open skies. I have obtained no reports from people in that part of the country. We thought we had a definitive check because Harvard College has now installed a photographic meteor station near or possibly inside the White Sands Proving Ground. Since the 12th of December, you correct me if I exaggerate here, re have been trying to determine the color and other character­ istics of the ten or 12 brightest meteors observed at that station. We still don’t knot what they saw. We know they were operating and they made ease photographs, but Captain Neef can probably tell you the red-tape channelization impedimenta that has dropped out any detenninp+ions better than I can. Conference on AERIAL E Pago 11y^®5JIA Captain Eeef: Veil, it’c one of those things; it's a Wavy contract and they are not at liberty to divulge what they find, so we have to go through Washington, the Bureau of Ordnance, to get the information. Comdr, ifendelkorn: I believe I can get that information; as a matter of fact, I feel very certain that I can. Just a matter of approach. Dr. LaPuar I feel certain if I had contacted Dr. Fred Whipple, for example, I could have obtained it, but his other occupations keep him away from that installation. And actually I felt as a meteor!st, it might be wise to have 031 appeal for information rather than to ask for it directly* Captain Reef: They did tell us they weren't using films which were going to be susceptible to these colors. Dr. LaPea: But, of course, they ere making constant visual observations and if you were able to determine visual observations 100 miles from Los Alamos don’t reveal the occurrence of bright green fireballs, I think it would be significant. I don't know why they should avoid the Southern-half of the State. Coodr. kindellcorn: Let us say if these had been at extremely high altitudes, they would have been visible from White Sands without any question. Captain Seef: This one of the 30th definitely was visible from White Sands because Ocraaander Holloman 7 and his wife and one of his assistants and his wife saw it from there. Dr. LaPas: On the other hand, you have evidence like that of Profee nor Talbot ? now in charge of the optical trajectory section down there, an experienced astronomer, & member of the American Meteor Society. I talked with him about this, onl ho has observed notliing out of the ordinary. I don’t think anybody, I mean in the line of green fireballs, in this area has been observing as much an he does. I don't see how he could miss sighting some of these. Question: What explanation do you have for this? Dr. LaPau; The only explanation is the one I gave in the beginning and had my ears promptly boxed for. I think these are defensive manoevvers of some higher U S. Command and they are practising in the neighborhood's? the regions they are going to defend, so naturally your localization of light near the atomic boat installations, but boy, am I scolded for that.’ Even Dr. Kaplan of the FAD ? tells me no, no, the FAD would know all about it, and they don’t have any facts. Dr. Bradbury: Is this the physicist Kaplan! Dr. LaPaz: Yes. Kaplan is my old boss- He was chief of the operational analysis section when I was....director there....... * During Kaplan’s visit Conference an AJERIAL PH Page 12 to the University of New Mexico, where he was lecturing, we called a confer­ ence with Major Godsoe and other interested parties. He gave a brief resume of the observations that had been made to date. Mow, Kaplan is one of the charter members of the American Meteor Society, and he said certainly these could not be conventional meteorite fells. He, of course, mentioned as other people do who have not gone into it more thoroughly, the possibility of abnormal types of meteorite falls, that might come in from a peculiar direc­ tion or might droop at very low level, but I don't think he was able to explain the absence of sound. Dr- Teller: Did I understand you correctly that the velocity of the object appears to be some 50 kilometers per second? Dr. LaPaz: Ho. In the case of the green fireballs something between 3 miles per second and 12 miles per second. Depending, you see, if you choose one ruled map or another. For example, let me illustrate how that affects the velocity determination. Thia is the one I think possibly best represents the observations of the case of the fireball of December 12. That is the path I assume the Los Alamos observers saw the same point of the curves that the Starvation Peak Observers did, likewise to the point of disappearance. If we deny that possibility, the path might shorten to this dotted line. (Dr. LaPaz worked on maps with Dr. Teller, explaining paths.) Dropping from 25 to some­ thing between 11 and 12 miles. The January 30 observation gave us our first long path. Dr. Teller: How long was it? Dr. LaPaz: The first observations we had here indicated ..... That was because of errors in the determination of the azimuth at the point of begin­ ning, mad® due to the faulty transit they used. But that’s correct that the path runs over 100 miles. Dr. Teller? And how long does It take? Dr. LaPaz: Duration estimates range from 5 to around 1U seconds. I think that a 10 second average is about the beat, that would give about 10 miles per second. Dr. Bradbury: Green is not an unknown color in meteors? Dr. LaPaz: If I were to rewrite the report that I first presented on that sub­ ject, instead of saying "rarely observed” this color green, I think I would now say "never observed”. You sometimes see green, Dr. Bradbury, but it is a blue­ green. The blue-green color is rare, but it is observed. For instance, Dr- Sherman Smiths observation was essentially a blue-green, but on the blue side. Dr. Bradbury: What other colors do you see in meteors? Conference on AERIAL PHENOMENA Page 13 Dr. LaPaz: Whites chiefly. If you look closely and without interference from outside lights, yellows, oranges and rads. Dr. Bradbury: But it's apparently a yellowish-green we’re talking about here. If you can see a bluish-green, you can also see yellows and whites. Dr. LaPae: There is some defect, possibly in the vision, that requires a pretty high intensity in that yellow-green before it’s noted in a meteor fall. Dr. Bradbury: Looks like green? Dr. LaPaz: Yes it does, that’s perfectly true. Now here's a peculiar property of those yellow-green fireballs - seme people will refer to them as red. The only explanation that I can think of is they report afterwards that they see what is an exposure to a very green-bluish light rather than the light itself - I don’t know if that is correct. And, incidentally, due to your observation, I don’t know how to explain the inability of meteor observers to report this renegade color, but I simply know it doesn’t occur. You go through long lists, like those of the American Meteor Society, you will find, I imagine, not 1 in 100 where a green is mentioned. Even in the case of the ? showers, where you have large numbers of very bright colors - let me recall something that all of you must have seen. The....shower of October 9, 19^6 - anyone hers who saw that? There were large numbers of extremely bright fireballs at that time. Kaplan himself recalled that they were blue, maybe blue-green, but never yellow green. And I observed those under very favorable circumstances - we were flying at about 20,000 feet in a B-29. We had no absorption effects at all. They definitely did not show hues of green. Dr. Bradbury: You mentioned the noise problem also. The noise occurs only when the meteor itself blows up, breaks up? Dr. LaPaz: No, that isn't strictly true. You have, in addition to the hollow sound, the normal sound of the breakup of the.... You have headwind; you’re near the path. You get a real shock; for instance, we have....apparently broken up by that headwave, shock wave, in the case of the Norden County Falls. And then from the turbulence and reflections all the way along the path, you will have a rumbling which may endure not for the matter of a tenth of a second, but for minutes, end they're real rough. Dr. Bradbury: But these occur fairly close to the trajectory? Dr. LaPaz: No. In the case of the Norden County Falls again, they were heard clear down to....City. Shakes buildings that far away. The ..... Falls were heard up to 300 miles froa the point of impact. Dr. Bradbury: Large number of observations...... Dr. LaPaz: No, there again I checked very carefully because I was concerned. I am trying desperately to give a logical explanation to the absence of sound. Conference on AERIAL PHEKOMEHA Page 1U I have found in the literature only three cases where no detonations, no rumblings were reported. One of those is the Belgium observation in 1855, and I think should be discounted because meteorists hardly existed at that time. Some falls occurred and were not reported at all. The other two are reasonably recent observations - one in 1921 end one in 1922. They occurred, however, in the deep South where negroes, I think, were the only observers. Even there, the aliasing of the meteorites as they fell through the air, was reported. I know of no case of an actual meteorite where at least the whizsing of the falling body coming down through the air has not been reported. Dr. Bradbury: ...... ? Dr. LaPaz: Meteorite falls, I believe that was the way you phrased it? In the case of a shooting star, of course, you never hear a thing because the entire mass is, very kindly, vaporized before it gets, say, within 50 miles of the earth...... Sot only noises, but accompanied by such noises that persons or animals are really frightened out of their wits. For example, we have a beautiful case where 2 horses killed themselves - in the Borden County Falls - they may have been felled by meteorites, but I'm inclined to think that the noise frightened them until they dashed into a ditch ...... Animals go crazy. Comdr. Mandelkora: Do you think it unusual no fragments are found? Dr. LaPaz: I certainly do. And I think it unusual, not only in the case of the green fireballs, but in view of the fact that a great fall, like the ..... fall of October 30, 19^7, where for the first time we detected a bit of the interest on the party of the military, there too we recovered nothing. October 30, 19^7, about 4:^8 in the afternoon there was, what appeared to be, a tremendous meteorite fall over the reservation area - the Four Corners Area. We got there within a very few hours, had excellent observations, went back time and again, exhausted ground search, CAP people in airplanes, we had a radio centered, we had radio controlled Jeeps and a lot of people out walk­ ing around - not a trace. I can't give you a color on that because.... Comdr. Mandelkorn: Ordinarily, when phenomena of that nature occur, you are able to recover seme material? Dr. LaPaz: Yes, soma material is recovered almost always. If proper search is conducted. We have, by the way, very thorough air search conducted by Gill Field Corps of Intelligence Unit; Dr. Lansberg of the Research end Development Board, very kindly interested himself in the problem and the air searchers resulted not even in the discovery of a broken branch. The region is heavily forrested. If branches had been broken, I think they would have been detected. I baren!t classified that particular fall, however, with the green fireballs and for this reason: that left a train. Another thing which I might have mentioned - a normal meteorite fall ..... will produce a long enduring train visible by day and night. Luminous by night and by day, Conference on AERIAL PHENOMENA Page 15 illuminated, by the sun. In the case of the irons, it vill be very faint, but it’ll be there if you look for it. In the case of the Four Corners Fall, that train was observed and I m inclined to believe that it might have been a conventional meteorite fall. In the case of the green fireballs, to my knowledge, no such train has been observed. That question is always asked of people - did you observe a long enduring train; their replies were always negative. Comdr. Mandelkorn: Then you would say there were 10 incidents which are analogous to the green fireballs, with reports checked by a sufficient number of independent observers, that there is no doubt whatsoever of their occurrence? Dr. LaPaz: That’s right. Comdr. Mundelkorn: Then there are