Om kometer, peer review og kontroversiell vitenskap

[Amatør1]

Jeg kom over en svært så interessant historie om oppdagelsen av små kometer som hele tiden treffer jorda. Dette er forøvrig mest sannsynlig opprinnelsen til verdenshavene... og samtidig bidrag til en ørliten havstigning i vår egen tid. Ihvertfall en fascinerende historie, med flere fasetter:


"Every few seconds a "snowball" the size of a small house breaks up as it approaches Earth and deposits a large cloud of water vapor in Earth's upper atmosphere."

Historien har også mange andre elementer som er relevante i klimadebatten:

The Original Discovery

Her er noen utdrag, lese hele via linken over

"It all began back in 1981. On the third day of August a Delta rocket lifted off from Vandenberg Air Force Base carrying a pair of NASA satellites, both known as Dynamics Explorer, into elliptical orbits. One of these satellites circles the poles of Earth at an altitude ranging from 350 miles to 14,500 miles. I was responsible for three of the instruments aboard the satellite, one of which is an ultraviolet camera, built and operated by my colleague John Craven.

The pictures sent back from the ultraviolet camera on the satellite were spectacular. The remarkable auroral crowns encircle the poles of Earth, while the planet's dayside looks like a bright ball illuminated by a flashlight. This bright feature is known as the dayglow. Dayglow is produced by the interaction of sunlight with the atomic oxygen present in Earth's upper atmosphere. The ultraviolet light emitted by this dayglow is not visible to the naked eye but is within the range of the satellite's specially-designed camera. The emissions it captures are transformed into a normal photograph.

But the images of Earth we obtained beginning in late 1981 contained an unexpected feature. The blanket of dayglow was not uniform. It was speckled with dark spots. The black spots on the images were like flies walking across a television set. They were annoying. They were there from the start, on the very first images. Strictly speaking, these spots were areas of greatly reduced brightness. In other words, there seemed to be holes in the dayglow. There is no question about who saw them first. Everybody saw them. We would give talks and the black spots were there on the images for everyone to see. And everyone assumed they were noise--those random fluctuations in data that are due to chance.

[...]

It was tempting to simply remove the spots from the images and get on with the search for gravity waves. But you cannot alter data on a mere assumption. You have to have a reason. We needed to show that the spots were either detector noise, or produced by electronics on the spacecraft, or generated by computers on the ground. Only once that was accomplished could we eliminate the spots from the processed images and get on with our work.

Sigwarth worked very hard trying to solve the mystery. From time to time he would come into my office and say he was not having much luck with it.The year 1982 drew to a close. Sigwarth kept working on it. But he was unable to trace how the holes appeared on the images.

[...]

Sigwarth then programmed the camera so that instead of scanning the entire Earth, it would scan just a small portion of it. This allowed the camera to return to the same area more quickly. The series of pictures produced showed that a black spot would appear and disappear in a sequence of frames. The black spots seemed to be objects in motion. This was not characteristic of noise. Noise should appear at random all over the image. This indicated the presence of a real object.Sigwarth came down to the lab where I was working and showed me the data. He was very excited. I looked down at the pictures and congratulated him. I thought we were on to something.

[...]

By February of 1983 we had come to the conclusion that something,some kind of object, was absorbing the ultraviolet radiation between the camera on the satellite and Earth and producing the apparent holes in the atmosphere. The more we looked the more it seemed that our images were actually snapshots of the movement of these objects above the atmosphere. We began to suspect that these objects were meteors of some unusual sort.

[...]

Over this period of time Sigwarth and I analyzed over 10,000 images and learned a good deal about the black spots in the process. Our interpretation of the events continued to involve meteor impacts into Earth's upper atmosphere.By counting the spots in our images we were able to estimate the rate at which these objects appeared. This was the simplest measurement to do. We saw ten holes per minute on the daylight side of Earth. So we doubled that figure to obtain the rate of these objects over the entire face of Earth. There had to be about twenty such objects entering the atmosphere every minute. That was an alarming number of objects.

[...]

This explanation posed certain difficulties, all of which were more psychological than physical. When we calculated how much water we would need up there to produce a spot in our images, we came up with a figure of about a hundred tons. Anyone would tend to back off from such a large figure and initially we did too. Then we figured out how many such objects we needed to account for the holes in the images we observed over the course of the year. And it was not one, not a hundred, but ten million. There was the problem. One per year would not have been a problem. But ten million per year? Unfortunately, there was not much leeway in our numbers.

[...]

The size of the holes presented another problem. They were easy enough to measure. We knew the size of the area each pixel covered in our pictures and we knew the altitude of the spacecraft. But what looked like little dark spots on the images turned out, in reality, to be about thirty miles across. They could not be rocks because such large rocks would just smash the surface of Earth to pieces. These were clouds of water vapor.

[...]

The numbers were shocking. Earlier we had found that the spots on our images varied with the frequency of meteors falling into Earth. At first,we were elated. But when we sat down to think about it, we saw a disaster pending.The objects were just too big and too numerous to be just another nice little geophysical fact with no real impact on our thinking. But once we ruled out noise and ascertained that the spots were real, the next step, the interpretation, was trivial. The only way to interpret these events was in terms of ten million objects falling into Earth's atmosphere every year. That is an infall of material that is about ten thousand times more than anyone had ever imagined. So psychologically, emotionally, the interpretation was difficult to accept. But intellectually, it was trivial. There was no other reasonable explanation.

[...]

I began writing the first draft of the original small comet papers in December of 1985. Eventually I handed out a few copies to people for their comments, but not before spending many nights pacing the hallways of Van Allen Hall and pondering the consequences of such an action. The papers touched on many of the objections that such a large infall of comets would raise. What would their existence mean for Earth and Venus and Mars and the other planets? What was the lifetime of such objects? What kind of mantle did they need to survive repeated passages through the inner solar system? Where did they come from?

One of the copies of our original papers had gone to Thomas Donahue,a professor of atmospheric sciences at the University of Michigan. You cannot do any better than Donahue when it comes to experts on planetary atmospheres. I respected his opinion. Donahue looked at our papers and said that if we were right these comets would have brought in enough water, over the age of Earth, to produce the oceans.And of course he was right. I had not thought of it because I had always assumed that the oceans had always simply been here. So did everyone else.

[...]

Scientific journals rely on a rigorous review process to weed out inaccurate claims and research findings. Editors, if they are favorably disposed to manuscripts submitted for publication, send them to two or more scientists considered experts on the topic treated in the manuscript. The comments of these referees are returned to the editor, who then sends them on anonymously to the original author.This allows the referees to be candid and honest. Often, however, this power is abused.Those who are judging the merits of a manuscript are often in competition with the author for grants or recognition. Some scientists abhor this anonymity and those who know one another occasionally send their comments directly to the author of the submitted paper.

I had this kind of unspoken understanding with Donahue. He was one of the referees and he nearly exploded. He asked me not to publish the papers,the interpretation paper, in particular. The first paper was simply a description of the black spots and no one could deny that the black spots were there. The second paper was the interpretation. In it we spelled out that we were dealing with ten million, comet-like objects entering Earth's atmosphere per year, each one the size and weight of a small house. We also touched upon many of the topics this interpretation would seem to contradict, such as the origin of the oceans, as well as the lack of water in Earth's upper atmosphere, on Mars, on Venus and on the Moon, as much as we could cram, in other words, into four pages. This was the limit on the length of papers published in Geophysical Research Letters.

The other referee also recommended against publication. He said,Dessler told me, that "if this was correct, we would have to burn half the contents of the libraries in the physical sciences." It was a dicey situation for Dessler.The two people he had asked to review our papers had advised him not to publish.So Dessler called me and asked if I would withdraw the interpretation. He warned that its publication might destroy my scientific career. But I told him it was necessary.Without it people were likely to regard the black spots as a mere curiosity.

Donahue also begged me to come to my senses. He did not want the interpretation paper published. I think he was trying to be helpful. But he must also have been worried about the tremendous repercussions these findings would have for many fields of science, including planetary atmospheres, Donahue's own little niche. Yet despite two negative reviews and the "uncomfortable ramifications for the community at large," Dessler decided to go ahead with publication. The final decision always rests with the editor. Reviews are designed to guide, not bind.

[...]

Anytime you break new ground in science you get attacked. This is the basic conservatism of science. But it is necessary to put all new ideas on trial. I had some notion of what the response to these papers would be. I had been involved in many scientific debates before. But the reaction I received was like none I ever experienced. I was driving a bulldozer through dozens of the neatly planted fields of science and everyone was upset.

[...]

The notion of so much water falling in from space flew against all current observations and beliefs. Most likely the notion was wrong, so I had to make certain that it was not. I had done everything I possibly could to find something that said these objects could not exist. I only needed one big piece of evidence.Just one. A hundred pieces of evidence would not prove that they exist. But it would only take one to show that they did not. So I sat in libraries and read about astronomy, about oceanography, about geology, one field after another. And finally I decided that our findings must be published, no matter what the consequences. I could not live with myself otherwise. It was just morally incorrect. "

[Jostemikk]

Dette var kjempespennende, og jeg må innrømme at jeg aldri har hørt om dette tidligere. Ikke et pip.

Er dette stadig gangbar mynt? I så fall, hvorfor har vi ikke hørt om dette i forbindelse med klimaforskning og annet? Artig også å se at en forsker turte presse på for å få dette publisert, koste hva det koste ville rent karrieremessig. Etikk og moral er som regel ikke det som slår meg umiddelbart når jeg leser mine vanlige doser klimapublikasjoner.

[Amatør1]

Dette var kjempespennende, og jeg må innrømme at jeg aldri har hørt om dette tidligere. Ikke et pip.

Er dette stadig gangbar mynt? I så fall, hvorfor har vi ikke hørt om dette i forbindelse med klimaforskning og annet? Artig også å se at en forsker turte presse på for å få dette publisert, koste hva det koste ville rent karrieremessig. Etikk og moral er som regel ikke det som slår meg umiddelbart når jeg leser mine vanlige doser klimapublikasjoner.

Jeg kan ikke innestå for det hele, for dette var også til en viss grad nytt for meg, selv om kometer lenge har "fått skylden" for verdenshavene. Men her snakker vi altså om veldig mange, veldig små kometer.

Det er noen meget interessante opplysninger på FAQ-siden:


Is there any geological evidence to support the need for such an "outside" source of water as the small comets?
There is indeed. In 1999, David Deming, a geologist at the University of Oklahoma, published a refereed paper [Palaeo, 146, 33-51, 1999] which has attracted the attention of many scientists. His work points out that recent investigations of the movement of oceanic continental plates into the mantle, known as subduction, show that the loss rates for the water on this planet are very large as the plates carry the water deep below the surface. So unless there is an influx of water to our planet on time scales much shorter than its age of 4 billion years or so, our planet would be presently "dry as a bone." Remarkably the necessary influx of water from interplanetary space agrees quite well with what the small comets are calculated to be bringing to the Earth.

David Deming kjenner vi jo fra klimadebatten, det var han som fikk høre fra en av "klimaforskerne" at "we have to "get rid of" the Medieval Warm Period"



Videre, her til lands er vi heldige og kan natterstid om sommeren observere "nattlysende skyer" eller såkalte "noctilucent clouds".  Disse har jo manglet noen god forklaring, men her er det jamen småkometene som blir presentert som forklaring!! Det må i samme slengen påpekes at nattlysende skyer har blitt mer vanlige på våre breddegrader




Are noctilucent clouds produced by small comets?
The influx of small comets into Earth's atmosphere may help explain the source of water needed to form noctilucent clouds. These strange and quite beautiful clouds can be seen over the polar regions during the summer months. They are thin clouds, wavy or banded, colored silver or bluish white. They form at an altitude of about 55 miles, in the coldest part of the upper atmosphere, a relatively unexplored boundary known as the mesopause. No other cloud occurs so high in the sky. They are called noctilucent clouds because they can only be seen against a dark sky when illuminated by the setting sun. These clouds require considerably more water vapor than can be expected at that altitude from ocean evaporation. No one thoroughly understands why these clouds exist. But rocket-borne experiments sent up by aeronomers--those who explore the upper atmosphere--to probe these clouds have shown that the clouds are composed of ice crystals formed around meteoric dust particles--a finding that suggests small comets might indeed be responsible.

En annen type skyer vi har her til lands, er perlemorsskyer, eller "nacreous clouds". Jeg spekulerer på om disse har samme forklaring. Igjen har disse blitt mer vanlige de seinere år.




En meget kontroversiell påstand som blir presentert, er denne:

Where do the small comets come from?
The small comets do not come from the Oort cloud located far beyond the orbits of the planets, but from an inner belt of cometary material beginning just beyond the orbit of Neptune. To explain the constant bombardment of the Earth by small comets, a large, dark, as-yet-undiscovered planet must be regularly passing through the outer part of this comet belt where the small comets are thought to be located. The eccentric orbit of this dark planet is speculated to cross the comet belt once every 26 million years or so, sending swarms of small comets streaming into the inner solar system and toward the Earth itself.

Definitivt en dristig påstand!

[Amatør1]

Apropos:

Mystery cloud spotted on Mars by amateur astronomer

Skyen vises ca kl 01 nær kanten på planetskiven


Jeg har selv forsøkt å fotografere Mars, det er bare mulig hvert annet år når Mars står i opposisjon. Selv da er det meget vanskelig, og det vi ser her er av fantastisk god kvalitet. Animasjonen er satt sammen av enkeltbilder tatt over en periode på 1-2 timer, Mars roterer rundt egen akse på ca 24.5 timer.

Hadde jo vært interessant om dette var en slik komet-sky?

[Amatør1]

Her er et bilde av nattlysende skyer slik de kan ta seg ut sett fra Sør-Norge en sommernatt. Dette bildet tok jeg for snart 6 år siden, en natt da disse skyene dominerte nordøst-himmelen. Opprinnelsen til slike skyer, som er svært høyt oppe i atmosfæren, har lenge vært et mysterium, men jeg lurer på om vi nå har fått et svar med denne mini-komet-hypotesen.

[attachimg=1 width=1600]

[seoto]

Et svært interessant bilde, Amatør1! Det lyset må ha gitt en spesiell følelse?
Du verden så mye det er tilbake å finne ut av! 

[Jostemikk]

Et kjempefint og interessant bilde, Amatør1.

Denne historien får meg til å tenke på The science is settled, og hvor lite verdt vitenskaplig konsensus kan være. Det minner meg også vagt om noe jeg mener å ha sett på en av kunnskapskanalene angående hva som har bragt vann til jorda, og hvor det kommer fra. Mener å huske at de nevnte to mulige kilder, og at vann og vann kan være to "forskjellige" ting. Gikk det ikke helt ned på molekylvekt? Hmm. Hukommelse er en fæl ting å måtte stole på.