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Advanced Concepts / Re: Imaging Proxima b?
« Last post by hop on Today at 01:56 AM »
What about keeping a very close eye on the trajectories of faint Kuiper Belt objects and determine when, and from what vantage point(s) in the inner system, they might occult Proxima Centauri.
Observable occultations of any star by KBOs are quite rare. The odds against one happening over Proxima Centauri with exactly the right geometry to let you measure something useful about the planet, while visible from a suitable observatory are... astronomical.

A useful chance alignment that does happen is microlensing of background stars by Proxima Centauri and its planet(s) . There was such an opportunity in Feb 2016 (see https://arxiv.org/abs/1401.0239). I'm not aware of any results published yet, but even if no planets were detected, it should reduce some uncertainties about the star.
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Mike Brown sticks his neck out as regards planet nine.

Quote
Mike Brown
3h
Mike Brown ‏@plutokiller
@Rickie99_ I predict within 3 years it'll be found.

https://mobile.twitter.com/plutokiller

What say people on this prediction?

Reminds me of Babe Ruth...pointing to center field before hitting a home run over the Wrigley Field center field fence in the 1932 World Series.

Is it possible that Brown's team has already found a candidate object and are making follow-up observations?
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Thanks Doug. Answered my question, although I'd like to track down the materials remaining on it if any.

Saw this on wikipedia entry "On 1965 Jack Swigert, who would later be one of the Apollo 13 astronauts, softly landed a full-scale Gemini capsule using a Parawing stiffened with inflatable tubes along the wing’s edges".

Don't know where that came from.

Really?  I had not run across that one before.  I was also not aware that they ever put a pilot inside a full-size Gemini capsule and landed it with the wing.  In fact, to be honest, I have to doubt that entry, since the only full-scale boilerplate tests I know of achieved in-air deployment by removing the inflatable structures -- by 1965, I don't think they were flying anything but the permanently-deployed wing on the scale model (which had structural members in it) and the deploy-in-flight tests which, again, didn't use inflatable struts.

Of course, I'm certainly not all-knowing, so there could have been crewed tests of full-scale boilerplates of which I was not previously aware.  I'd be interested in hearing more details about them.

Tracked down the reference to "How To Fly Without A Plane"

Quote from: Robert Zimmerman
The tests at NASA continued. In 1965 Jack Swigert, who would later be one of the Apollo 13 astronauts, softly landed a full-scale Gemini capsule using a Rogallo wing. Here the wing’s size was increased by several magnitudes, and the structure was stiffened not with buckram but with inflatable tubes along the wing’s edges. Later the Golden Knights, the Army’s parachute-exhibition team, made the world’s first parachute jumps with it. They used the double wing arch of Rogallo’s original kite multiplied many times over, with repeated arches placed side by side, creating what is today called a paraglider.
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Advanced Concepts / Re: Imaging Proxima b?
« Last post by gbaikie on Today at 01:44 AM »
As I mentioned elsewhere, a mission to the transit cone might be worthwhile - I'm hearing different comments regarding our relationship to the plane of the Proxima system, however.

So it's visible from southern hemisphere. And I am not good with star chart but I think it's about 35 degree below solar plane??
Or need to use southern lunar pole.
Hmm can see it from a crater? Well if more towards far side of Moon [say 80 degree latitude] and would be about 35 degree above the Sun.
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As far as tourisim opportunities are concerned, having rations be intended from the start to be COOKED by a crew member naturally allows the position to be upgraded to a CHEF, so that the billionaires who can afford to take a year in space can eat like billionaires.

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After reading many papers and abstracts on Uranus and Neptune missions, I suspect the Uranus is the only reasonable candidate for an orbital mission.  1) As redliox points out, to get to Neptune in any reasonable time, you need exotic technologies such as aerocapture to slow down, 2) a flight to Uranus will be shorter, so data comes back sooner, 3) Uranus is much closer, so data rates will be higher. 

Uranus is a pretty interesting system.  One or two of the moons may be ocean worlds.  There's the rings.

New Horizons provides an existence proof that a flyby mission to Neptune would fit within the New Frontier budget.  However, the last Decadal Survey explicitly decided against a proposal that would have (from memory) flown past Saturn, Neptune, and a KBO.  Too little science return for the dollar.
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ISS Section / Re: US EVA-37 - September 01, 2016
« Last post by Targeteer on Today at 01:40 AM »
DEXTRE is retrieving the replacement RPCM--I think
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Advanced Concepts / Re: Imaging Proxima b?
« Last post by the_other_Doug on Today at 01:35 AM »
What about keeping a very close eye on the trajectories of faint Kuiper Belt objects and determine when, and from what vantage point(s) in the inner system, they might occult Proxima Centauri.

If you're lucky, and the occulting KBO is rather dark in nature, you could do intensive spectroscopy during after starset and starrise.  Remove the signal from the KBO and from Proxima Centauri, and what is left would have to be reflected from Proxima b.  If it was a short occultation, you could strengthen your interpretation of the data's origin if it primarily appeared either just after starset or just before starrise.

Of course, you would need for Proxima b to be separated from its star sufficiently, and in the right orientation (either leading or trailing) right at the time of the occultation for this scheme to work.  But, hey, if there are favorable occultations visible from Earth, we could at least try it.

It's not exactly imaging, but it's spectroscopy that could give us a lot better idea of the characteristics of the atmosphere, if it has any.  It's direct measurement and use of light reflected from the planet, so in that sense, I guess it's imagery of a sort... :)
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I know that. But in those areas, and in the current one, they are looking for an object that they have pretty much defined. My point is that if P9 ends up not conforming to that definition, they may never find it at all, having already missed it in those other areas, as well as the current - because - they didn't recognize it.
Beyond a certain point if it doesn't conform to the definitions, it's not the "Planet 9" they predicted. The whole reason "Planet 9" is more interesting than many previous "something big could be out there" type predictions is that it's fairly specific.

Of course it's possible that Planet 9 was missed due to bad luck in one of the regions thought to be ruled out, but by definition the odds of that are low. If the surveys of the highest probability areas turn up empty and no other data invalidates the Planet 9 hypothesis, people will likely go back and look harder at the others. If all else fails, LSST will likely answer the question definitively.
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Looking isn't the only possible way to detect a large object like this.  If it is large enough it may generate a magnetic field, so there may be radio emissions.  All the known outer planets emit radio signals.  And we have very sensitive tracking of our spacecraft on interstellar trajectories, moving off in different directions.  If one of them is slightly affected by the gravity of a large distant object more than others, we might detect its presence that way.  We had the so-called Pioneer anomaly, eventually explained as a very subtle effect caused by the vehicle itself.  If we can detect that we might detect other anomalies in Voyager trajectories, or from reanalysis of the Pioneers.  I would assume these ideas are being worked on (or have been considered and rejected), though I have not heard anything. Just saying - looking isn't everything.
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