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3 votes

What exactly was "The curse of Sisyphus" and why did it take so long to find out about the radar detection of its companion?

Here are notes on the CW radar measurements in 1985 updated in 2013. echo.jpl.nasa.gov/asteroids/Sisyphus/sisyphus.html They could not detect it with the ranging technique, using a single wavelength ...
eshaya's user avatar
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5 votes
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What is the explanation for discrepancies in RA values at Santa Maria Degli Angeli e dei Martiri in Rome

Here's a little script I wrote that uses Astropy to calculate the right ascension of these stars in 1703 AD, accounting for both proper motion and precession of the equinoxes. It's based on an earlier ...
Roy Smart's user avatar
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3 votes

What exactly was "The curse of Sisyphus" and why did it take so long to find out about the radar detection of its companion?

The article is humourously named, but there doesn't seem to any particular curse mentioned. The authors describe a process of getting a accurate light curve, establishing that there is a 2.4 hour ...
James K's user avatar
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2 votes

First satellite of an asteroid (or double asteroid) ever imaged by delay-Doppler radar?

The second table here provides the radar detections RADAR DETECTIONS IN CHRONOLOGICAL ORDER The first radar binary asteroid detection was in 1985 by continuous wave radar but not reported until 2007. ...
eshaya's user avatar
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4 votes

Since John Herschel was first to make a photograph on a glass plate in 1839, why was the first astronomical photograph not taken until 1840 by Draper?

One possible answer is that Herschel probably understood that the state of the art in photography in 1839-1840 wasn't astronomically useful. If you look at Draper's photograph of the Moon, it's pretty ...
Peter Erwin's user avatar
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-1 votes

Since John Herschel was first to make a photograph on a glass plate in 1839, why was the first astronomical photograph not taken until 1840 by Draper?

John Herschel took a photo in September and Draper took one the following March. That's only a 6-month interval at a time when photography didn't exist. You're asking why Herschel didn't think of ...
Miss_Understands's user avatar

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