Archiver > GENEALOGY-DNA > 2011-05 > 1304476985

From: "Diana Gale Matthiesen" <>
Subject: Re: [DNA] Picture of a SNP?
Date: Tue, 3 May 2011 22:43:05 -0400
References: <>,<781564FAD39749BDACF4B1DED086C56A@kenPC> <COL116-W408C6A04A13170ACF61506E49E0@phx.gbl><A78C175A6C0C4A6293B2D715681568FA@kenPC> <005401cc09af$6c9b36e0$45d1a4a0$><DC3B98229B68428F8419AFA194A702FC@kenPC>
In-Reply-To: <DC3B98229B68428F8419AFA194A702FC@kenPC>

It all depends what you mean by "seeing," which is the reason both of
us are putting the word in quotes. You will, in fact, never "see" an
atom or molecule with visible light -- because they are too small.
You need to use some other medium to image them, then enlarge and
translate that image into something we can see.

> -----Original Message-----
> From: [mailto:genealogy-dna-
> ] On Behalf Of Kenneth Nordtvedt
> Sent: Tuesday, May 03, 2011 1:09 PM
> To:
> Subject: Re: [DNA] Picture of a SNP?
> "Seeing" is now also done with nano-probes which detect and quantify
> the
> electric fields surrounding atoms and molecules.
> "I see said the blind man as he picked up a hammer and saw."
> -----Original Message-----
> From: Diana Gale Matthiesen
> Sent: Tuesday, May 03, 2011 10:30 AM
> To:
> Subject: Re: [DNA] Picture of a SNP?
> An object has to be larger than the wavelength of the medium used to
> detect it, or it will be "invisible" to that medium. Atoms and
> molecules cannot be seen using visible light because they're smaller
> than the wavelengths of visible light.
> The DNA molecule is about 2.5 nm wide and its constituent atoms are
> even smaller, while the wavelength of visible light is in the range
> of
> 390-750 nm. Atoms and molecules can be "detected" with higher
> frequency (shorter wavelength) electromagnetic radiation, such as
> X-rays, but the idea of ever "seeing" atoms or molecules is a
> non-starter.
> Diana

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