October 5, 2013
Our earth moves around the sun at an average speed of 62,000 miles per hour. That’s besides the point that we rotate 1,000 miles per hour (at the equator). Every object is moving in outer space, very quickly. There is nothing that is sitting still out there even if it doesn’t look like it’s moving. Our solar system has gone around the whole Milky Way many times. If we send some travelers out to another solar system, how are they going to know if they are going in the right direction? First off, that’s a long way off if that ever happens. But if science can practically freeze our bodies into hibernation, maybe we’ll send some poor souls off to find us another earth. Maybe they’ll send frozen eggs. Who knows how we’ll be packaged.
Keeping these space travelers on the right path will require something more than our GPS satellites. But we’ve got a lot of other things to choose from in space that give off signals. We’re getting signals right now from a lot of telescopes. Meaning, we’ve got Hubble, we’ve got radio telescopes, x-ray, infrared telescopes…you name it. Right now it looks like we can get reliable signals from pulsars. If the space travelers have some x-ray detectors (telescopes) there are signals from these known pulsars that can be used. The software…before I go further….can you imagine? depending on our technology? We did go to the moon 50 years ago. I guess we can do it, with a lot of backup systems I hope.
Your position right now on earth is pretty easy to find with our GPS satellites. The accuracy is about 15 meters but there’s more accuracy available than that. I had a patient studying environmental science who said they use satellites to track centimeter movements of geology. I think the accuracy is even better than that depending on the who needs to know kinda stuff.
I wrote a post about using autonomous driving cars. I think they’re really getting closer to becoming a reality. I suppose the early adopters will be paying/paving the way for the rest of us. LiDAR costs more than the car. But what’s interesting is how LiDAR determines points in space called voxels. You can look that word up in wikipedia but it represents a volume in space related to other volumes….a square amongst other squares.
But you have your own free space detector and it’s a cool thing in itself. It’s called proprioception. Might be a new word but this is how you use it. Say for example you’re reading this and reach over to turn the light off or pick something up without seeing it. Your brain is aware of your hands position in space without even seeing it. Well, that’s just one example of how our brain knows our bodies position even though we’re not looking at it.
So, pulsars, GPS, LiDARs and proprioception….we somehow will find our way around in space but goodness gracious we get lost a lot.
August 24, 2013
Most of us have probably seen those beautiful pictures of galaxies and nebulas that seem to frequently show up on websites. Maybe I’m just noticing them more since I’m interested in them. And until I became interested in them I never thought much about how the pictures were taken. The hubble telescope, as well as other research telescopes, get those pictures from special instruments that can detect a wide range of wavelengths….sorta detecting like our eyes but the detectors on the telescopes can receive other wavelengths that we can’t see. You know the antenna on cars? Or in your cell phones? Or satellite dishes? They detect wavelengths we can’t see. The hubble telescope detects all kinds of signals (wavelengths) from ultraviolets to infrareds and beyond. Our bodies do detect ultraviolet and infrared but not our eyes so we do have some special detectors. Our skin can darken from ultraviolet rays and we can detect heat as an example of infrared. But we don’t see those, we only feel them or notice the results later.
Here’s an example of infrared detection here on earth. The colors you see in the picture are industry standard representations that show cool as blue colors and red as warm in these infrared detectors. I previously wrote a post about hot and cool colors which differ from how they are used below.
And here’s an example of an ultraviolet detector for the sun (glasses with photochromic coatings like Transition lenses also work by UV activating):
The hubble telescope detectors are quite a bit more advanced obviously. These telescopes don’t take pictures like our cameras. How then can we explain all the colors in the hubble pictures that we see if they aren’t colors that our eyes can’t detect? What the scientists get from many of these telescopes is a bunch of monochromatic (more than 50 shades of gray too) black and white boring pictures and data (boring to you and me). There’s a lot of artistic license that goes into making these pictures as beautiful as they are and makes them definitely more exciting to look at. That is the purpose too. Astronomers enhance the telescope data to visually represent different gases that are in the nebula or different energies that are detected in galaxies. How these colors are chosen is also somewhat artistic as well. Enhancing depth using contrasting shades helps the overall effect.
If you want to read a little more about how these colorful pictures are created I’ve got some links below! Oh, pictures of Mars more closely represent what we might actually see with our own eyes compared to those galaxy and nebula pictures.
and this one about early artistic methods: http://io9.com/
potentially hazardous near-Earth object 1998 KN3, (the bright green dot upper left)