10 ms·

They should make km the default unit and not miles....

by spaetzleesser 6y ago

lmilcin 6y ago
Actually, NASA uses metric system internally. Imperial units are probably used for general public convenience.
- spaetzleesser 6y ago
  Considering that one of NASA's roles is to inspire young people to enter STEM I think it would be important to promote metric as much as possible.
  - lmilcin 6y ago
    I don't see how the choice here can promote STEM. Do you think kids find it sexy to talk about meters, kilograms and degrees Celcius rather than feet, miles, pounds and Fahrenheit? I can't fault for choosing what is more understandable to the target audience.
fckthisguy 6y ago
As another commenter said, NASA uses metric. During the stream, you can hear the various teams giving measurements in metric, whilst the media gave coverage in imperial. It's a pretty interesting video from that perspective, as you can hear the two "realities" being translated for the intended audience.
mulmen 6y ago
Ever been on an airplane? Altitude was almost certainly measured in kilofeet. As noted in other comments, NASA (like the rest of the United States [1]) does use the metric system. But it doesn’t matter. Nothing about the metric system makes it uniquely suitable to landing on Mars. Or space travel in general. What matters is a consistent standard. Internally NASA could use Armstrongs. Where 1 is the weight or height of Neil Armstrong at KSC on July 16, 1969 at 13:32:00 UTC. It doesn’t matter. As long as it is consistent. [1]: https://en.m.wikipedia.org/wiki/Metrication_in_the_United_States https://en.m.wikipedia.org/wiki/Metrication_in_the_United_St...
- dieortin 6y ago
  It does matter. See the errors caused in the past by using the imperial system. The metric system has a number of advantages.
  - mulmen 6y ago
    The errors were not caused by the imperial system. The errors were caused by using the imperial system and the metric system. Specifically in expecting one system and getting the other.
    - bernulli 6y ago
      The thing is, though, that you have these conversions even within the imperial system (https://en.m.wikipedia.org/wiki/Imperial_units#/media/File%3AEnglish_Length_Units_Graph.svg https://en.m.wikipedia.org/wiki/Imperial_units#/media/File%3...) but not within the metric system. My experience with U.S. students is that they are having a much harder time making sense of the imperial system (that they are used to) than doing problems in metric, even though they don’t use it in everyday life.
      - mulmen 6y ago
        Ok, so? First off, you linked to a list of english measures which are not used in the US. Nobody uses fathoms or barleycorns. Here is the list of actual US customary units: https://en.m.wikipedia.org/wiki/United_States_customary_units https://en.m.wikipedia.org/wiki/United_States_customary_unit... Second, none of that is relevant to landing on Mars. The only problem space where metric has an advantage is in converting between meters, kilometers and millimeters. That’s great, and it’s easy to learn. But it doesn’t suddenly make all problems of distance easier to solve. If I am traveling toward Mars at 47 meters per second it doesn’t help me to know that is also .047km per second. And converting to kilometers per hour involves using base 60 twice anyway because metric time is unwieldy. In reality none of your measurements are going to be nice round numbers. Mentally converting from meters to km might be nice sometimes but it’s essentially a party trick. It won’t help the lander make decisions. The hardware doesn’t inherently work in base 10. Does NASA mix meters and kilometers? Isn’t that the same problem that destroyed the Mars Climate Orbiter? The fact is the units are irrelevant beyond just being defined and used consistently. Also, I can’t think of a situation where I need to convert miles to feet. My bike ride is six miles, I’m never going to express that in feet. If I need to describe the size of a thing in a room I will probably use feet, maybe inches if it is small. Probably not feet and inches. I wouldn’t use miles at all. Easy conversion between those units just isn’t a problem that comes up. It’s more important to me to have reasonably sized units and that the person I am communicating with understands them.
boilerupnc 6y ago
NASA has experience in unit foul-ups. Mars Climate Orbiter is the $125M poster project reminding everyone of the importance in having consistency in units. "At 09:00:46 UT Sept. 23, 1999, the orbiter began its Mars orbit insertion burn as planned. The spacecraft was scheduled to re-establish contact after passing behind Mars, but, unfortunately, no signals were received from the spacecraft. An investigation indicated that the failure resulted from a navigational error due to commands from Earth being sent in English units (in this case, pound-seconds) without being converted into the metric standard (Newton-seconds). The error caused the orbiter to miss its intended orbit (87 to 93 miles or 140 to 50 kilometers) and to fall into the Martian atmosphere at approximately 35 miles (57 kilometers) in altitude and to disintegrate due to atmospheric stresses."[0] [0] https://solarsystem.nasa.gov/missions/mars-climate-orbiter/in-depth/ https://solarsystem.nasa.gov/missions/mars-climate-orbiter/i...

They should make km the default unit and not miles....

lmilcin 6y ago

Actually, NASA uses metric system internally. Imperial units are probably used for general public convenience.

spaetzleesser 6y ago
Considering that one of NASA's roles is to inspire young people to enter STEM I think it would be important to promote metric as much as possible.
- lmilcin 6y ago
  I don't see how the choice here can promote STEM. Do you think kids find it sexy to talk about meters, kilograms and degrees Celcius rather than feet, miles, pounds and Fahrenheit? I can't fault for choosing what is more understandable to the target audience.

fckthisguy 6y ago

As another commenter said, NASA uses metric. During the stream, you can hear the various teams giving measurements in metric, whilst the media gave coverage in imperial. It's a pretty interesting video from that perspective, as you can hear the two "realities" being translated for the intended audience.

mulmen 6y ago

Ever been on an airplane? Altitude was almost certainly measured in kilofeet. As noted in other comments, NASA (like the rest of the United States [1]) does use the metric system. But it doesn’t matter. Nothing about the metric system makes it uniquely suitable to landing on Mars. Or space travel in general. What matters is a consistent standard. Internally NASA could use Armstrongs. Where 1 is the weight or height of Neil Armstrong at KSC on July 16, 1969 at 13:32:00 UTC. It doesn’t matter. As long as it is consistent. [1]: https://en.m.wikipedia.org/wiki/Metrication_in_the_United_States https://en.m.wikipedia.org/wiki/Metrication_in_the_United_St...

dieortin 6y ago
It does matter. See the errors caused in the past by using the imperial system. The metric system has a number of advantages.
- mulmen 6y ago
  The errors were not caused by the imperial system. The errors were caused by using the imperial system and the metric system. Specifically in expecting one system and getting the other.
  - bernulli 6y ago
    The thing is, though, that you have these conversions even within the imperial system (https://en.m.wikipedia.org/wiki/Imperial_units#/media/File%3AEnglish_Length_Units_Graph.svg https://en.m.wikipedia.org/wiki/Imperial_units#/media/File%3...) but not within the metric system. My experience with U.S. students is that they are having a much harder time making sense of the imperial system (that they are used to) than doing problems in metric, even though they don’t use it in everyday life.
    - mulmen 6y ago
      Ok, so? First off, you linked to a list of english measures which are not used in the US. Nobody uses fathoms or barleycorns. Here is the list of actual US customary units: https://en.m.wikipedia.org/wiki/United_States_customary_units https://en.m.wikipedia.org/wiki/United_States_customary_unit... Second, none of that is relevant to landing on Mars. The only problem space where metric has an advantage is in converting between meters, kilometers and millimeters. That’s great, and it’s easy to learn. But it doesn’t suddenly make all problems of distance easier to solve. If I am traveling toward Mars at 47 meters per second it doesn’t help me to know that is also .047km per second. And converting to kilometers per hour involves using base 60 twice anyway because metric time is unwieldy. In reality none of your measurements are going to be nice round numbers. Mentally converting from meters to km might be nice sometimes but it’s essentially a party trick. It won’t help the lander make decisions. The hardware doesn’t inherently work in base 10. Does NASA mix meters and kilometers? Isn’t that the same problem that destroyed the Mars Climate Orbiter? The fact is the units are irrelevant beyond just being defined and used consistently. Also, I can’t think of a situation where I need to convert miles to feet. My bike ride is six miles, I’m never going to express that in feet. If I need to describe the size of a thing in a room I will probably use feet, maybe inches if it is small. Probably not feet and inches. I wouldn’t use miles at all. Easy conversion between those units just isn’t a problem that comes up. It’s more important to me to have reasonably sized units and that the person I am communicating with understands them.

boilerupnc 6y ago

NASA has experience in unit foul-ups. Mars Climate Orbiter is the $125M poster project reminding everyone of the importance in having consistency in units. "At 09:00:46 UT Sept. 23, 1999, the orbiter began its Mars orbit insertion burn as planned. The spacecraft was scheduled to re-establish contact after passing behind Mars, but, unfortunately, no signals were received from the spacecraft. An investigation indicated that the failure resulted from a navigational error due to commands from Earth being sent in English units (in this case, pound-seconds) without being converted into the metric standard (Newton-seconds). The error caused the orbiter to miss its intended orbit (87 to 93 miles or 140 to 50 kilometers) and to fall into the Martian atmosphere at approximately 35 miles (57 kilometers) in altitude and to disintegrate due to atmospheric stresses."[0] [0] https://solarsystem.nasa.gov/missions/mars-climate-orbiter/in-depth/ https://solarsystem.nasa.gov/missions/mars-climate-orbiter/i...