New Horizons Arrives at Kuiper Belt Object Ultima Thule


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This is the first Kuiper belt object that a spacecraft has visited. Nobody is sure what it will look like. Preliminary indications are that it seems kind of peanut shaped, and may end up being two small objects in contact (fused?) or orbiting each other very closely. (I want it to be an ancient million-year-old alien starship!) More realistically, it will be interesting to know what objects like this are made of. Rock? Ice? (Which essentially constitutes rock out there in that cold. Our silicate rocks would be fluid or even vapor at hot Jupiter temperatures. It's all relative.) Hopefully we might learn something about what organic chemistry is taking place on its surface.

Unclear how much viewers will initially be able to see. This thing is way out beyond forsaken and unloved former-planet Pluto. (With a giant heart on its side, it remains every child's favorite. They identify with it.) Not only will there be a speed-of-light delay in the signals arriving here (about 5 light-hours to Pluto and more to this object), I believe that the data transmission rate is low so it will take some time to download data and photos. So the juicy details might not be made public immediately. Apparently the plan is for the spacecraft to blurt that it is awake and recording as it passes its target, then 4 to 5 hours later when it's done observing it will reorient to point its high-gain antenna at Earth and begin transmitting high-res photos and stuff. So there may be something like a 10 hour delay before images come in. (Maybe more if there's signal processing necessary to clean up the images.)

Schedule of streaming media events here:

NASA will have coverage (panel discussions with planetary scientists and live updates) here

And there will also be a stream from Johns Hopkins' Applied Physics Laboratory in Laurel MD (where the mission is being controlled) here (dunno if these are the same events that NASA will be streaming, I imagine so):

There will be (and already have been) quick updates on New Horizons' twitter pages too:

As usual for NASA missions, the Australians are on the case:
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I love watching new discoveries unfolding in real time!

New Horizons is six light hours from Earth, so data on what it did last night (our time) is only now trickling in. (Six light hours would seem to be 1/1,460'th of a light-year.) Besides the relativistic delay, data transmission from that little vehicle so far away is slow. Imagine that little bar creeping along agonizingly slowly as you download something.)

Jonathan McDowell seems to have access to the raw information almost as fast as NASA is receiving it and is translating it on his twitter page.

He says, "Signal received! And now in lock with telemetry. NH is alive... now to download system status.

RF (radio system) is green - all good there. Thermal state also good.

What's "FC"? - flight control maybe? But what does that include in that context?

GNC (Guidance, Nav and Control) and Propulsion and (electrical) Power green.

C&DH - command and data handling - good, the disk drive is pointing where it should be. The "SSR" is solid state recorder, which is basically a solid-state disk drive. It has 'pointers' which say how full the disk is. The fact that those pointers are where they are meant to be means that the expected number of files have been written to the drive.

Now they just have to copy the contents of the drive to a computer on Earth - sort of like doing a backup! That'll only take them about 2 years, to copy the full drive... but we'll get some data later today.

I'm told FC is probably flight computer. also "Planning" was green, which means they think NH actually used the right instruments in the right order for the right amount of time. So, everything looks good.

The one thing we don't yet green from yet is Navigation... and we don't know for sure if Ultima Thule is actually in any of the pictures. So still a few hours to be a bit nervous."

Edit: Jonathan McDowell's source for the above seems to be this video, originally played live on NASA TV and JHUAPL about an hour or two ago, showing the system status data first coming in and the various systems desks reporting their status. The data starts to arrive about 30 minutes into the video so you can skip forward to that.

Jonathan McDowell has gotten hold of this pre-encounter photograph of Ultima Thule apparently taken by LORRI (who is New Horizons' Long Range Reconnaissance Imager) as New Horizons was still approaching and blown up mercilessly (it's very pixilated) that shows that the object is very elongated. He speculates that it might be two objects in close proximity (a 'binary').

Some additional commentary on that photograph from the Planetary Society here

(I still want it to be a derelict alien starship floating out there, perhaps with a propulsion unit and a habitation unit, connected by a thin neck.)

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(I still want it to be a derelict alien starship floating out there, perhaps with a propulsion unit and a habitation unit, connected by a thin neck.)
Don't we all

And i can think of at least one poster to the forum would tick this as vindication

Don't we all

And i can think of at least one poster to the forum would tick this as vindication


I was thinking of him when I wrote it.

Although, I'd be willing to bet that when better photos start coming in, starting in the next few hours, that alien-starship hope will be dashed.

(Can you imagine the excitement if photos somehow did reveal it to be a 20 mile-long spaceship? Every country on Earth would be absolutely throwing limitless money at space exploration (hello BFR!), hoping to get a salvage party out there to collect all the alien knowledge and technology they can.)

Turning to something entirely different, it seems that New Horizons has its own music video! former Queen guitarist Brian May, who happens to have a PhD in astrophysics! (From Imperial College, not too shabby.)
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Photos coming in: What the astronomers call a 'contact binary'.

These first photos are from an hour before closest approach and better high-res photos are expected to be downloaded in due course. Coloring of this object in visible light is distinctly red, like Pluto and most of the outer solar system bodies, due to organic chemistry on their surfaces.