New Horizons fly-by


#1

You may have read about the fly-by of an object 1 billion miles further out than Pluto.

I just read that the transmitter on the spacecraft has an output power of 15 watts.
Amazing… IMHO.

The key to communication is the signal to noise ratio (S/N). To keep the s/n high enough to detect while limited to such low power, one needs a tiny bandwidth (and other little tricks like processing gain). So the data that New Horizons collected in the flyby will take a couple years to be received successfully over that tiny bandwidth data link.

I knew one of the main antenna designers at JPL almost 30 years ago and a few other people there because we (my office) funded them for some special projects. And we published together. Seems like ancient history and yet it was at that time this mission was conceived.

In August 1992, JPL scientist Robert Staehle called Pluto discoverer Clyde Tombaugh, requesting permission to visit his planet. “I told him he was welcome to it,” Tombaugh later remembered, “though he’s got to go one long, cold trip.”[24] The call eventually led to a series of proposed Pluto missions, leading up to New Horizons .

I no longer work within that circle of people but I would say they (JPL) was a technological jewel of the nation. The people were the best and the brightest.

Congratulations to those who started this mission and to those who continued it that led to today’s flyby.


#2

I watched their event last night. Brian May was there, which was kinda cool. He premiered a video that he created for the event.

It was pretty cool. The event itself was a bit of a let down as there wasn’t any visual of what was happening, but it was still cool to know that it was happening out there and that we made it happen.


#3

Yeah, the engineering vision that goes into these things is intense. They have so little to work with and so much to do…

I assume that they get great priority on transmission spectrum slot selection. They would need an incredibly low noise sectrum slot for spread spectrum, or one single frequency. And I assume that they ED/EC the crap out of the code which further slows reception.


#4

Thule-e the snowMAN!


#5

By the way, they expected to take about 10 gigabytes of data for the imaging, which is going to take ~20 months to download here on Earth.


#6

The most astounding NOVA I have ever watched aired January 2, 2019, on PBS. Essentially, it was a real time presentation of the fly-by of Ultima Thule … airing only one day after it occurred! A HUGE! applause for the folks who produce that show and, of course, also for the NASA team that made it happen.