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I don't have daily access to the journal Icarus so when I read the New York Times article Asteroids and Adversaries: Challenging What NASA Knows About Space Rocks; Two years ago, NASA dismissed and mocked an amateur’s criticisms of its asteroids database. Now Nathan Myhrvold is back, and his papers have passed peer review. and saw that the article was accepted for publication in this journal where I can't read it for a few days, I though I would ask here instead.

The NYT article is worth reading in full for a better perspective on the situation, but here's a bit:

For the last couple of years, Nathan P. Myhrvold, a former chief technologist at Microsoft with a physics doctorate from Princeton, has roiled the small, congenial community of asteroid scientists by saying they know less than they think about these near-Earth objects. He argues that a trove of data from NASA they rely on is flawed and unreliable.

Since 2011, a NASA project known as Neowise has cataloged the sizes and reflectivity of 158,000 asteroids, and it claimed that its diameter estimates were often within 10 percent of the actual size. Dr. Myhrvold said the uncertainties were much greater, largely because NASA researchers were using data from a satellite designed for observing distant objects, not nearby asteroids. “The science is terrible,” he said.

Now his arguments have been published in Icarus, one of planetary science’s most prestigious journals.

“I’ve gotten people to agree I was right,” Dr. Myhrvold said.

The paper in question is An empirical examination of WISE/NEOWISE asteroid analysis and results Icarus, 314, pp 64-97, 1 November 2018.

Question: What would be a concise yet clear way to explain what it is that this paper asserts is wrong, both quantitatively and procedurally, with the WISE and NeoWISE asteroid data?

So far I've found some hints in the 2016 New York Times article How Big Are Those Killer Asteroids? A Critic Says NASA Doesn’t Know. such as:

It struck Dr. Myhrvold that the albedo calculations of the Neocam team violated a basic tenet of physics known as Kirchhoff’s law of thermal radiation, which says shinier objects radiate less heat.

A simple demonstration of that, Dr. Myhrvold said, is the shiny chrome cooking surface of a restaurant hibachi grill. A dark grill surface would bathe diners in uncomfortable waves of heat. The Neocam models failed to take into account the effects of reflected sunlight, he said.

He then took a closer look at Neowise, too. One aspect Dr. Myhrvold found curious was that in more than 100 instances, the Neowise team reported asteroid diameters that matched exactly what had previously been determined by other methods like radar measurements and spacecraft flybys. “I think it’s a pretty strong smoking gun that something is wrong,” he said.

note: In scientific debate, especially where the database is extensive and the analysis is complex, it takes time to work through to a conclusion. So the existence of the paper, or this question, should not be taken as a conclusion that there is in fact anything at all "wrong" with the NeoWISE asteroid data.

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  • $\begingroup$ @GdD if "better" means receive a better answer, I'm not sure. WISE/NewWISE is a NASA spacecraft, and I believe the data is analyzed by NASA people, so in this particular case I think the probability is higher that someone familliar with the aspects of the data and analysis will more likely see it posted here than posted at Astronomy SE. At least that's my thinking. $\endgroup$ – uhoh Jun 20 '18 at 12:10
  • $\begingroup$ Published today and slightly related: "NASA will host a media teleconference at 1 p.m. EDT Wednesday, June 20, to discuss a new report detailing U.S. plans for near-Earth objects (NEOs) that could pose a hazard to Earth. While no known NEOs currently pose significant risks of impact, the report is a key step to addressing a nationwide response to any future risks." $\endgroup$ – uhoh Jun 20 '18 at 18:17
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Upon reading "An empirical examination of WISE/NEOWISE asteroid analysis and results":

As I understand it, nothing is wrong with the data obtained from the missions. What is wrong is the interpretations/inferences drawn from the data.

As I understand it, the data consists of multi-spectral analysis of various asteroids. From that data, the sizes of those objects were inferred. A goodly portion of the inferred sizes were correct (being cross checked with confirmed measurements). However, a large portion of size inferences were incorrect with error tolerances as large as ~50% in some cases.

The attached quotes propose possible flaws that might attribute to the inaccuracies found in the aggregate data (the inferred sizes). One such flaw was that the data sets used to cross check the results has inaccuracies of its own. The other states that the math in their algorithm was wrong especially in certain bands.

Overall, it seems there is not yet a definitive consensus regarding the accuracy of the aggregate data due to a lack of more data.

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  • $\begingroup$ I think the Kirchhoff’s law violations, as well as the "exact matching" data points are troubling to some as well, no? $\endgroup$ – uhoh Jul 20 '18 at 11:28
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    $\begingroup$ Right, the fact that there were exact matches makes that a very interesting aspect to further research. $\endgroup$ – anon Jul 20 '18 at 11:31

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