Exposing PseudoAstronomy

February 25, 2015

Why Do Young-Earth Creationists Even Try to Pretend at Science?


There are a few main young-Earth (Christian) creationism organizations in the world that rise to the top in terms of reach and output and attempt to use science to justify their beliefs. Among those I would name three: Answers in Genesis (US-based, headed by Ken Ham), Institute for Creation Research (US-based, founded by Duane Gish), and Australia-based Creation Ministries International (which I think was also founded by Ken Ham, but AiG and CMI severed ties several years ago, fairly acrimoniously).

Over the past eight years, I have dealt with articles by all three, and other. In fact, my early posts mostly consisted of ripping through YEC claims. That’s mostly fallen by the wayside as posts have (regrettably) decreased over the years as I became more and more busy with work, but occasionally I’ll still see something that I want to comment on.

But more on that momentarily.

What these Big Three do, among other things, is attempt to do science and/or report on science. They’ve realized that as each new scientific discovery has borne out that contradicts their sacred tome, more and more people will leave their strict, literal interpretation of their religious writings.

Ergo, they have to try to show that science somehow supports something that they’ve said and believe.

I’ve also done numerous posts on this blog about the scientific process and why – to be a good scientist – you must also be a skeptic: You must find a way to remove your own bias(es) from the experiment. You must be able to objectively look at the data and also try to disprove what you want to think is the case in order to see if the data are ambiguous or really do exclusively support the conclusion. You have to think of all the other interpretations and gather observational evidence that those explanations are not valid. The process is not infallible, but it’s a heck of a lot better than a dogmatic approach.

Which, despite all the façade, is what creation “science” really is. And, surprisingly, I couldn’t’ve said it better myself than what Creation Ministries International wrote a few days ago in trying to answer a reader’s question about when stars were formed:

“what you propose is clearly ‘science’-driven not text-driven”

Blasted “science!” Always interfering with the Bible! (or at least their reading of it)

But, realizing it or not, this clearly demonstrates that what YECs do is not science: They start with their conclusion and will modify or massage or tweak or somehow shove the data into that hole to make it come out right. Or, simply deny that it exists (such as Kent Hovind denying there are reversals in Earth’s magnetic field, or almost all YECs denying accuracy of radiometric dating). This handy flowchart I made several years ago sums it up nicely:

Flow Chart Showing Faith-Based "Science"

Flow Chart Showing Faith-Based “Science”

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February 16, 2015

Podcast Episode 126: The Facts and Misconceptions Behind Funding in Science, with Dr. Pamela Gay @starstryder


The sordid subject
Of the coin: How scientists
Are – and are not – paid.

This is another episode where I don’t focus on debunking a specific topic of astronomy, geology, or physics pseudoscience, but rather I focus on a topic of misconceptions related to science in general: How scientists are funded. This is done via an interview and bit of discussion with Dr. Pamela Gay, who cohosts the very famous “AstronomyCast” podcast and is the director of CosmoQuest.

The topics are varied, but it remains focused on some of the misconceptions of how research is funded and the real process behind it. It’s also a bit depressing, but I can’t always have light-hearted topics like Planet X isn’t coming to kill you.

Since this is an interview, it is a somewhat longer episode (54 minutes), there is no transcript, and there are no other segments.

The episodes for the next two months should be focused on Comet Hale-Bopp and have a brief interlude of another interview with the chair of the program committee for a major planetary science conference, and what they do when they get submissions that seem like pseudoscience.

February 4, 2015

New Horizon’s First Images of Pluto from Its Approach Phase – What’s Going On?


Introduction

New Horizons is a spacecraft headed to Pluto. It launched nearly a decade ago, but it will arrive in July of this year and do a fly through the system. Doing lots of amazing science.

One of the instruments is LORRI, a long-focal-length camera that will be the prime imager for much of the mission because it will be able to take the highest spatial resolution images. It will also be used (was being used and is being used, too) for optical navigation — make sure we’re headed in the right direction.

Just a few minutes ago, on the anniversary of Clyde Tombaugh’s birth (the guy who discovered Pluto), NASA released the first image from LORRI of Pluto and its main satellite, Charon, taken during the Approach Phase. There’s a lot going on here – one point in particular that I just know is prone to misunderstanding later on – so I want to talk a bit about this image.

Disclaimer

I am involved with the New Horizons mission. I am not a NASA employee. This is my personal blog and everything on it is my opinion, are my words, and is done completely independently (time-wise, resource-wise, person-wise) from my work on New Horizons. In fact, it is on record that this blog is legally distinct from my professional work. Nothing I say here should be taken as an official statement by NASA or the New Horizons team.

Resolution / Pixel Scale

That out of the way, let’s get to the meat of this post. Also, I’m going to use “resolution” and “pixel scale” a bit loosely here, so pedants need to forgive me right away.

LORRI is an amazing camera. It is a 1024×1024 pixel detector, and each pixel has an effective angular size of 4.95 µrad (micro radians, or about 1.02 arcsec). 1 arcsec is about the width of a human hair from 10 meters (33ft) away. (source)

At the moment, New Horizons is around 200,000,000 km away from Pluto. That’s okay, it still has 5.5 months to get there. Pluto is approximately 1180 km in radius. That means, from some simple trigonometry (remember SOHCAHTOA?), Pluto is about 1.2 arcsec in radius, or 2.4 arcsec in diameter. Charon is very roughly half Pluto’s diameter, so it’s around 1.2 arcsec in diameter. Charon and Pluto orbit on opposite sides of their center of mass, which means they are around 8.6 Plutos away from each other, or around 9.1 arcsec separated.

Okay, lots of numbers there. Basically, that means that right now, if we had perfect optics, Pluto is about 2 pixels across, Charon 1, and they’d be around 8 pixels away from each other, max (since their orientation on the plane of the sky is not perpendicular to the spacecraft right now).

(No) Perfect Optics

No such thing exists. Given the best, most perfect optics ever, you can never get infinitely fine details. This is because light will behave as a wave, and give rise to Airy disks and patterns meaning that the light will spread out as it travels through the optics. Unless you had an infinitely wide optical system.

When you factor everything together about the optics and system and detector and other things, from a point source of light, you get a point-spread function (PSF). This is the practical, measured spreading out of the light. In astronomy, we often measure the PSF based on fitting a Gaussian distribution to a star, since a star should be a point source and just cover one, single pixel.

With a telescope aperture of 208mm for LORRI, and a passband of light centered around 0.6 µm (red light), the Airy disk should be around 1.22*0.0006/208 = 6.8 µrad. That’s around 1.4 LORRI pixels. Amazing coincidence!

Actually, not. When designing an instrument, you typically want to just about over-sample the Airy disk. You don’t want to under-sample because then you’re losing valuable resolution and information. You don’t want to over-sample because then you’re just wasting money on a detector that is too “good” for your optics, and other issues that come about when you have small pixels. So, designing a system that’s around 1-3 pixels per Airy disk is good.

When you go to a practical PSF, it’s going to be a bit bigger just because no system is perfect.

What’s the Point?

Oh yeah, back to Pluto.

First New Horizons Image of Pluto and Charon from Approach Phase

First New Horizons Image of Pluto and Charon from Approach Phase (©NASA/APL/SwRI)

Let’s put these parts together: Right now, Pluto should be around 2 pixels across, Charon 1, and a separation of around 7-8 pixels. But, add in the PSFs due to the laws of optics. That means that the light should now be spread out a bit more.

And that is why this image looks like it does. It’s also been enlarged by 4x, such that each original LORRI pixel has now been resampled. So, if you look at the image NASA released, and you blow it up a lot, Pluto looks like it’s around ten pixels across, and Charon around five.

To repeat: The released image shows Pluto to be around 10 pixels wide, and Charon around 5. Despite the theoretical values now (2 pixels and 1 pixel, respectively). That’s because (1) the PSF spreads the light out because we live in a world with real and not ideal optics, and (2) the released image was enlarged by a factor of 4.

Moving Forward

New Horizons is zipping quickly along. In May, it will surpass all previous images taken and we will truly be in new territory and a new era of discovery (so far as imaging the Pluto system — note that the other instruments have already taken a lot of data and are learning new things). That best image that exists so far of Pluto shows Pluto to be approximately 8 pixels across.

And that’s why I started this post out by stating, “one point in particular that I just know is prone to misunderstanding later on.” So, today, NASA released an image that shows Pluto with as many pixels across as what it will take in late May, when it will have that number of pixels across.

See why I wanted to bring this up now? I can just hear the pseudoscientists claiming that NASA is lying about the power of the New Horizons telescopes, they’re deliberately down-sizing images (later, based on images released now), and various other things. While they’ll still almost certainly say that, at least you know now why that’s not the case, and what’s really going on now versus then.

There are only 2 (well, about 4, since it’s 2×2) “real” pixels in the Pluto disk right now, the others are interpolated based on expanding the size to make the image look nice for this release, celebrating the image and Clyde Tombaugh’s birthday. In four months, we’ll have all these pixels, but they won’t be based on a computer algorithm, they’ll be “real” pixels across Pluto taken by LORRI. Convolved (“smeared”) with a PSF that’s about 1.5-2 pixels.

February 1, 2015

Podcast Episode 125: The Black Hole Conspiracy


Black holes: Are these dense,
Massive objects for realz, or
Are they just Sci Fi?

This is a bit different from a straight-up old-school “debunking” episode where the emphasis is more on the process of science and process of elimination rather than solid, cannot-be-dismissed evidence for something. That’s because, by definition (we think), black holes cannot be directly observed. That’s why I use a part of a blog post by Mike Bara as a very rough outline to go through some of the theoretical reasons for why we think black holes exist and then some of the observational evidence from material interacting with the theoretical objects.

This episode continues the Logical Fallacies segment and introduces you to the Burden of Proof fallacy. Which is a tricky one. There are also some old stalwarts like Argument from incredulity, argument from ridicule, ad hominem, straw man, and argument from authority.

And, for the first time in what seems like a year, there’s Q&A!!!

I’m still doing my listening “research” for the Hale-Bopp episodes, which is looking like there’s so much material that I may turn it into a three-parter. We’ll see. Hard to say at this point. It’s slated to be the next episode, but I may have to postpone that if I haven’t finished listening in time, and I’ll do a different episode instead. I’m also trying to line up at least two future interviews, but given past experience, I’m loathe to announce them before they’re recorded.

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