Discoveries in the Physics & Astronomy shop | Science, curiosities, and surprises
Summer is progressing quickly, and it won’t be long before it’s toy kit time once more, including this multicolored assortment of silicone poppers! Available in different colors and sizes, over time you learn which ones pop the best.
Marbled performs better than solid colors.
Pink is often the best. A good one can nearly slap the ceiling from bench height.
No certainty as to why. But they sure are fun!
It’s not just telescopes at the Observatory. We also have a spyglass. What’s the difference?
There are a variety of potential optics for a telescope, using reflectors to reflect and focus light, using refractive lenses to bend and focus light, using mirrors to turn a beam around corners, using these in combination. Each has its pros and cons, and careful optical design and precise manufacturing work to gather lots of light, to provide good resolution and magnification, and to correct for optical aberrations.
And in doing all of that, the image reaching your eye or the camera sensor gets flipped upside down. Also in reverse, if you’ve got a mirror in your optical train. When looking at stars and deep sky objects, that’s not a big deal. “Up” is arbitrary in space. For terrestrial viewing, however, up matters. Seeing that incoming pirate ship upside down is disorienting. So a good spyglass keeps up as up.
It does so by using a Galilean refractor design, which has a concave lens in the optical assembly to avoid the upside-down flip. The resulting telescope is necessarily longer than a comparable refractor with convex lenses, and thus heavier. That weight tends to limit the possible objective aperture size, and the practical magnification limits are low. Still: very effective for spotting Edward Teach at a distance, or for identifying the four largest moons of Jupiter.
Binoculars, incidentally, manage to keep the world upright thanks to a set of prisms between the objective lenses and the eyepieces. Yet another handy trick in the optical design toolkit.
Sometimes you just have to love the directness of the manufacturers of scientific apparatus and equipment. “Sensitive Research Instrument Corporation” is not, by any standards, snappy. But it is clear about their product line.
An accuracy guarantee of 0.25%, standardized by Louis Miller on 10/29/62. Charmingly hand-written on this label affixed inside the case. (Sadly, no one marked this one with the price.)
Still in the original box, of course. It’s unclear who the target market is or was for SpongeBob-branded golf balls, and yet here they are. Enjoy?
Not presented entirely without comment, as it’s hard to contain the urge toward snark. Yes, we know what this is and why it’s useful; yes, we know what they mean by “gender” and how F/F looks the same but changes things. Yes, yes.
At any rate: the cables which once needed this adapter are gone, as is the equipment it carried electronic messages to and from. Now we just have a block of metal and plastic and the opportunity to squint and say, “I’m not sure that’s how that’s supposed to work.”