Andrew Dalke's Comments

Looks like I could stick my hand through the bottom and be able to catch a falling plate.
Maybe I should go there and try! Checking ... Err, no. At almost $5,000 and 30 hours of travel to fly to Xi'an it's rather out of my league. (I honestly didn't expect it to be *that* expensive.)
Abusive comment hidden. (Show it anyway.)
The characterization "the first computer bug was quite literally a bug" isn't quite correct. "Bug" was used in the Mark I, before the famous bug mentioned here. See https://chsi.harvard.edu/harvard-ibm-mark-1-language. Also, Hopper's oral account at https://archive.org/details/podcast_from-archives_grace-hopper-howard-aiken-th_1000425230042 says it was a man who taped the moth into the computer’s logbook. ("the operator got a pair of tweezers ... and below it he wrote “First actual case of bug being found.”)
Abusive comment hidden. (Show it anyway.)
There are plenty of people on Earth who want a sustainable city for inhospitable climates. Why not start there? Argentina pays a lot of money to keep their Antarctic colony going, for example. There's plenty of cheap land in our cold deserts, shipping is a lot cheaper, and survivability is rather higher, so I would expect sustainable cities here first, But of course, this is link is more marketecture than anything else. Sigh, I'm getting old and blasé.
Abusive comment hidden. (Show it anyway.)
A problem with that interpretation of Giovanni Stanchi's picture is that Giuseppe Recco's Still-Life with Fruit and Flowers (ca. 1670, so essentially the same time as Stanchi) shows a much more normal looking watermelon. Stanchi's watermelon looks more like modern "hollow heart" watermelons, likely due to impropert pollination. (Of course I nearly only buy mass-produced store-bought fruit and veg so have little experience with produce outside of that conformity. I'm basing my opinion here on what I've read elsewhere, not personal experience.)
Abusive comment hidden. (Show it anyway.)
The article says the proposed vehicle uses nuclear thermal propulsion, not nuclear pulse propulsion. I used the average distance to Mars, because the link refers to it as "on average around 140 million miles away". Mars 2020 is using low-energy Hohmann transfer orbit. A three month transit requires a higher-energy orbit, resulting in a shorter travel distance than a low-energy orbit. I don't know how much shorter. My goal was to show that the overall g-force could be very low, though I made the wrong assumption about how the engine operates. A longer trip needs less energy and less (integrated) g-force.
Abusive comment hidden. (Show it anyway.)
No much. Figure average distance to Mars is 229 million km, and ignore the solar well delta V so it's acceleration 1/2 way and deceleration the other half, or 115 million km in 60 days. 115 million km / (60 days)2 = 0.0043 m/s2 or about 0.00043 g. Assuming it were slow and gradual like an ion thruster ... and I see now that I'm completely wrong about that. Reading https://en.wikipedia.org/wiki/Nuclear_thermal_rocket now, and I still can't figure it out. :( My guess is, slow and steady rather than a high-g force, in order to keep the operating temperatures cool.
Abusive comment hidden. (Show it anyway.)
Firefox's "Private Window" page says: "While this doesn’t make you anonymous to websites or your internet service provider, it makes it easier to keep what you do online private from anyone else who uses this computer." 'Course, we all know that most people don't read things like that.
Abusive comment hidden. (Show it anyway.)
The Wikipedia entry for Gollum at https://en.wikipedia.org/wiki/Gollum#Characteristics says: In the first edition of The Hobbit, Tolkien made no reference to Gollum's size, leading illustrators such as Tove Jansson to portray him as very large.[7] Tolkien realised the omission, and clarified in later editions that Gollum was "a small slimy creature."[T 3]The Two Towers characterises him as slightly larger than Sam;[T 17] and later, comparing him to Shelob, one of the Orcs describes him as "rather like a spider himself, or perhaps like a starved frog."[T 18]
Abusive comment hidden. (Show it anyway.)
  1 reply
If you need to planets to be on the same side of the sun as the Earth then there's a 0.5^7 chance on average that would happen, or on average nearly 3 days per year. Also, Pluto is very near Jupiter in the sky (see https://heavens-above.com/PlanetSummary.aspx?lat=0&lng=0&loc=Unspecified&alt=0&tz=UCT ) so potentially visible. But at magnitude 14.4 you'll need about an 8-inch telescope to see it, if I read https://en.wikipedia.org/wiki/Apparent_magnitude correctly. The next dimmest, Neptune, is mag. 7.9 which can be seen (in dark skies) with binoculars.
Abusive comment hidden. (Show it anyway.)
Login to comment.


Page 12 of 51     first | prev | next | last

Profile for Andrew Dalke

  • Member Since 2012/08/04


Statistics

Comments

  • Threads Started 575
  • Replies Posted 188
  • Likes Received 356
X

This website uses cookies.

This website uses cookies to improve user experience. By using this website you consent to all cookies in accordance with our Privacy Policy.

I agree
 
Learn More