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"Omega tau" made a really nice podcast a while ago about how Planet Labs is approaching Earth observation. That podcast goes into the details how the company and the satellite constellation came to be and what novel approaches they're using. Definitely worth listening: http://omegataupodcast.net/204-earth-observation-at-planet-l...
This is fascinating - especially the talks about the advantages of using COTS electronics.
Once upon a time, the latest and greatest in electronics was produced by military, scientific, and spaceflight applications, with commercial uses being spinoffs that were often up to a decade behind. Now the situation is reversed; consumer electronics are where the innovation is happening, and military/space systems are finding ways to repurpose that technology.
You can access their monthly imagery for free by creating an account at planet.com. I use it to track the progress of infrastructure and other land development projects near me. You can also create time lapse animations of a particular area, which is a super fun way to watch a road or a highway being built.
When I signed up last year I also got a free two week trial period where I could see the daily data. Looks like these days they even let you see what coverage they have of the daily data with a free account, but at very low resolution.
You highlight a region of the planet and they find you all the past imagery of that region. Though most of the daily results are a few strips that pass through the region, with some (or most) of the region missing. They haven't accomplished their ideal of "a picture of the entire earth once a day" but still one of the coolest companies out there.
They looked me up on LinkedIn using my email address and called by boss to ask me about the service.
What is he resolution like? Is it as good as Google's aerial imagery that they show with their maps? (or Bing's)
I thought they EOL'd the free offering?
I can't believe I've never wondered this before, but I wonder how possible it is to deliberately create a satellite-blocking cloud above one's own property. What height and size it would have to be, etc.
It's called anthropogenic clouds, and it's possible but requires certain weather conditions to work: you need a source of water vapor that can saturate the air, and a stream of cold air to condensate that vapor. Then it's possible to launch particles into the air that would act as cloud condensation nucleus, and in theory it should start the cloud formation. Anyway, to hide a small area much easier solution would be to have a lot of smoke, or to artificially generate fog which is much easier to do than clouds...
Just make a big warehouse, or put your activities underground. That's what militaries do (also covered drydocks and berthing slots).
Just move to San Francisco. ;)
If you could track the satellite could you not shine a laser, or bright light (maybe a mirror reflecting the sun) directly at the camera to mess up the imaging while over your region?
Geodesic dome, cheaper and more durable. As added bonus it protects you from the heat.
One day we will likely dome cities: https://en.wikipedia.org/wiki/Old_Man_River%27s_City_project
For the people commenting on the Firefox+Linux issue: it doesn't work for me, and this is the error I get:
>Refused to create native OpenGL context because of blacklist entry: FEATURE_FAILURE_OLD_NVIDIA
So the real combination is Old NVIDIA drivers + Linux + Firefox. (Maybe not even Firefox, the issue might be inseparable from my old card. I'm not going to try it on Chromium.) The question is, why is my card blacklisted? I think it might be because of a security vulnerability that Chrome hasn't patched.
Agreed, I have an intel embedded thingamabob and it works fine. I wonder if there's a software rendering option in FF that will make it work?
> Parts of the landmass can also be missing due to complete cloud cover that day. See the Amazon, Central Africa, or Northern Australia for example.
Aka great places to start a terrorist or drug organization!
The invasion of Iraq got delayed by a few days due to cloud coverage. It would definitely impede surveillance to have clouds often blocking satellites.
This is where SAR imagery comes into play [1]. There are a few SAR constellations online and being worked on that are shifting the discussion about what we can track [2][3].
[1] https://medium.com/from-the-macroscope/its-always-sunny-at-o...
Absolutely great, I am sure we will need these kind of visualizations to survive.
But the planet needs a JavaScript programming competition with the challenge of minimizing CPU load of such fantastic presentations.
It would be so good to have one golden path to browser animations with the lowest energy consumption, one default framework that will be easy to use without deep knowledge of browser quirks and JavaScript optimization tricks.
We are wasting too much time.
Well, I would say, what we need and have is a rich ecosystem of JavaScript applications, which can and does guide both libraries and browser development. I'd say we need, the start-stop and often out-of-step (i.e. careful and experimental) shuffle toward standards. WebGL is just the latest waltz, but that visualisation is built on a bunch of foundational standards: TCP, HTTP, HTTPS, OpenGL, WebGL, etc etc
The computers that got us to the moon where highly efficient integrated circuits. But (I presume) they can't get us to mars.
Personally I'd advocate for messy, but rich platforms, which max out our CPUs in some applications; but give expression to the emergent desires of those who want to tinker.
We don't have time to miss-out on potential wins by working with rigid systems.
Really cool visualization!
Talking about visualizing Earth. Does anyone know of alternative visualizations/projections of Earth (other than globes and maps)?
For example, what would it look like if we could image Earth, entirely, from pole to pole, continuously, like a panoramic picture? (imagine the result as an impossibly wide picture that starts with one pole on the left and ends with the opposite pole on the right)
Thank you.
I don't think that this is exactly what you're asking for, but you can explore most "standard" projections below (definitely try out the first link described below):
- Take a look at [0], click "Earth" in the lower left corner, then try other projections (they appear as the "A", "CE", "E", etc. list). Drag the map around to set the projection's "center". The real time projection calculations are pretty amazing..!
- Go to [1] and toggle all of the categories ("Wall Maps", "Maps of Hemispheres", etc.) by clicking them. The maps are not dynamic / cannot be dragged around (like [0]), but this is a more complete reference list (similar to Wikipedia's list of map projections [2]). The rest of the site is also absolutely incredible (I recommend taking ~1 hour to go through the whole list of projects one by one).
[0] https://earth.nullschool.net/
[1] http://www.radicalcartography.net/index.html?projectionref
So many questions:
1. How did they get 150 satellites into low orbit?
2. Is it becoming a hazard to have all the satellites and space junk possibly making it difficult to launch anything down the road?
3. Aside from tracking the objects, has anyone made any calculations as to when these things will become a hazard?
1. Many of these satellites are cubesats. They hitch rides as secondary payloads on launches, and in batches. In Planet's case, they've launched many batches, some as large as 20-48 satellites.
2. Not really. Kessler syndrome is the general name for this phenomenon, but it's not a huge concern in LEO. In LEO, there is enough atmospheric drag to naturally deorbit spacecraft. For US based companies, regulations mandate that they have a deorbit plan within 25 years. For most cubesats, their orbits are low enough that they'll naturally deorbit within 5-7 years.
3. Most people generally think that any hazard in LEO will not be caused by launching more objects, but by having objects collide (or having some weaponry intentionally explode objects) causing debris that is spread more widely and too small to track. Currently JSpOC in the US tracks most objects the size of a baseball or larger in LEO and coordinates with various commercial and private entities to put into place plans for collision avoidance where possible.
1. They launched by piggybacking on rockets that were launching larger satellites. For instance, they launched 88 on this record-setting PSLV launch: https://www.nasaspaceflight.com/2017/02/indias-pslv-record-1...
2. People generally have a poor understanding of how vast space is. Congestion in specific low-Earth orbits is definitely a concern, but the devil is in the details. For instance, launching to Sun-Synchronous orbit (SSO) [1] above ~600 km is considered to pose significant risk to on-orbit assets, because of how many satellites are in SSO and the kinetic energy their carry, however to really assess the risk, you need to do a lot of detailed population studies (I've done some of this stuff). In a nutshell, launching more satellites can be generally considered to increase risk of on-orbit collision and fragmentation, but quantifying it requires a lot of maths and physics.
3. Yes! There's is extensive and on-going research on this topic. Most people know the Kessler Syndrome [2], but honestly space debris research goes a lot further than that. This review by J.-C. Liou is a great starting point: https://commons.erau.edu/cgi/viewcontent.cgi?article=1233&co...
They are launched in groups. Lots of them are really small.
I worked for RapidEye during the launch in 2008. Exciting times!
If I remember correctly, their planned lifetime for imaging was 7 years, so it's quite amazing that they're still active 11 years later.
Stupid question: how do they measure speed of the satellite? I mean, on the website they've mentioned the speed of one of their satellite as ~7.6 kmps. Is that the actual speed of the satellite or it's a measure of how much land the the satellite covers per second?
The orbital velocity and the ground track velocity only differ by about 6.6% for their 450km orbit, so it's not a big difference. But because they have a relatively circular orbit, you can use the formula sqrt(G*M/R) which gives 7.639km/sec -- so it looks like they are referring to true orbital velocity.
Can we receive the signal from these satellites ourselves like we can with the NOAA satellites?
Anyone familiar the pricing structure of Planet? I couldn't find that on their website.
this is incredibly cool. Thanks for sharing!
The picture of Monte Fitz Roy is breath-taking. Is there any way to access more of the pictures?
Lot of blind spots (straight stips), are they covered in next satellite revolutions?
I hope they start imaging at least parts of the ocean, like the great pacific garbage patch and other areas of particular interest for meteorologists and environmentalists.
I do not see daily updates on planet.com, at least for the free trial account I just created, and for my location (Eastern Europe).
For example, there is a damb nearby which was completed a few months ago, but is shown half-built in their map.
Isn't this like rolling shutter ? But I don't see any stretching of the maps.
Super cool!
I wonder why both clouds and ocean show up as black instead of as actual white and blue imagery respectively.
Are they saving money and bandwidth by not sending back "useless" imagery? Or something else?
Cool visualization. Would be neat if we could rotate the globe
Really cool tech! I wanted to apply for a job there, but in the end didn't because of their undisclosed military clients.
The visualization also does not show up with the 'Dark Reader' extension on, which is kind of odd.
Welp, the final vestiges of privacy feel like they are being removed.
Can’t see anything on the globe, just a circle.
"This visualization doesn't work right on Firefox+Linux, sorry! You could try Chrome/Chromium instead."
No Thanks.
that's great
Are we moving to the Chrome only world?