As Bill said, it is cruise missiles that can use terrain as a guidance system.?ÿ They typically fly knap of the earth while ICMB tend to actually leave the atmosphere for bit making it hard to pick out terrain in anything but the most general sense.
I spent a bit of time working for the agency that was responsible for creating the DTMs used by cruise missiles.?ÿ There were entire buildings full of semi-automatic mapping systems developed for the purpose.?ÿ 30+ years later you do the same thing on a your desktop using autocorrelation routines thanks to them.
The death of GPS would essentially break our finance system, our communications, our transport, etc etc etc
That is a certainty! I was in a gas station once when the pump shut off. I went inside to see if they could restart it and the attendant said "The satellite connection just went down - there's nothing I can do. We just have to wait for it to come back online." He couldn't open the register to make change so after about 15 mins. I just left more than enough cash to cover it and left.
ICBM (not icmb) is intercontinental BALLISTIC missile. The ??B?? means something?ÿ
Actually, originally designated IBM. The acronym was changed so as to not confuse it with International Business Machines.
(today's brief moment in history)
Actually, originally designated IBM. The acronym was changed so as to not confuse it with International Business Machines.
(today's brief moment in history)
Footnote, bottom of pg. 88?ÿ Soldiers of Reason ~ Alex Abella
Kind of makes you nervous about checking that Beidou satellite selection box in Access?ÿ ???? ????ÿ
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Fleming argued that China??s BeiDou satellite system ?? an alternative to the widely used GPS navigation technology ?? could contain ??a powerful anti-satellite capability, with a doctrine of denying other nations access to space in the event of a conflict.?
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Fir years I used T2, HP3800, and traversed around several counties at time, 30-50 mile leveling lines, the good old days.
Find control monuments, use Polaris obs, yeah. That??s still an option.
get out the RangeMaster, Tellurometer, FM walkie talkies, maybe some helicopter work?? like we used to do it.?ÿ
FWIW,
However much I reflect on the pre-GNSS days, I cannot generate enthusiasm for the Tellurometer. Of course it would be hard to find a functioning or complete set nowadays.
I did lament the movement of control from mountaintops to drive-able points.
Of course the early units did engage the user; unlike the current ??black boxes? now in use.
As for Polaris and other astronomical observations, I do not know where I might find a current ephemeris. Of course, I haven??t looked since Wahl??s site stopped updating them.
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Funny thing I just got 11 navstar NANUs
FCSTMX ?? coincidence?
new anti-jam or L2 encryption??
As for Polaris and other astronomical observations, I do not know where I might find a current ephemeris.
The MICA program would serve, except that I think there is a problem needing update to time offsets.?ÿ Here are the files. I bought the program and book, but that company seems to not offer it now. I think the files were created on public funding and the book proprietary.
Dropbox File (Private or Invalid)
@bill93?ÿ
I have been using MICA for quite a while. And I no issue with solar observations. Few arcseconds per Starnet.?ÿ
@bill93 Try the USNO site. As recent as 15 years ago they were still performing astronomical observations and using the data for chandler cycle and other things. You can also get time from them. ?ÿUTC -1 and such. GPS offset and all.
The USNO site was out of commission for a year or two. When i checked it recently they have a lot of functionality but I didn't find MICA nor a similar replacement for it. I could get dec and RA but not az el. Maybe I missed something.
There are also software functions advertised that seemed to be for incorporation in other developers' programs.
Did I miss some immediate functionality?
mica is not data reduction.
I pull a table of RA/Decl semi diameter. Sun Azimuth and elevation are calculated from RA/Decl.
I haven??t found a high accuracy sight reduction program. I use the RA/Decl in an Excel spreadsheet. It was back to the textbook and took a bit to write. (But I do a lot of solar azimuth observations.)
@Bill93 thanks for the MICA files. I only had a much earlier version, and the online update is no longer available. The MICA publisher, Wilmann-Bell, seems to have been taken over by AAS Sky Publishing, which still makes some of their products available, but not MICA.
A problem with the US Naval Observatory is that the next time the Congress fails to pass an appropriations bill, they might go offline. An alternate site for that sort of thing is the Horizons System, an online service to compute the positions of solar system objects. It's run by NASA and the Jet Propulsion Lab; if there is a government shutdown, I have no idea if it would continue operating.
A big problem with Horizons is it does not cover stars.
Another option is the printed Astronomical Almanac.
My procedure has always been to use a program such as SPADE or MICA to get azimuth of the body versus time.?ÿ Then all I need to calculate is differences of angles.
@bill93?ÿ
I pull 00:00:00 RA/Decl/SD for a year and create an ephemeris.?ÿ
For fun I use the camera/event timing in an old Z-12. And a Mils T2. Radio tower at 20 miles I routinely get better than 5?.?ÿ
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