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"But the early 1990s also brought a big breakthrough in an algorithm, known as symplectic integration, that reduced computational times by an order of magnitude."
then
"Because symplectic integrators don’t waste time rediscovering Kepler’s laws over and over, they run orbital simulations hundreds of times as fast as older methods do."
100 times as fast is two orders of magnitude.
Noob question: Why isn't it passing in front of stars? Are we seeing a sequential dimming of occluded stars along the plane of the ecliptic?
The fact is, we simply do not image enough of the sky on a regular basis to have all this imagery just lying around. We do have some pretty good all sky surveys, but they don't use telescopes big enough to see something like planet nine. That's why it takes a dedicated effort to discover planet nine. It'll take imaging huge sections of the sky multiple times with enough delay between them to be able to see separation in the position of the object. Such large telescopes are very expensive and rare so their time is very valuable and in high demand.
Distant stellar transits will happen but we're not monitoring the entire sky 24/7 to the degree needed to spot all of them. If we were we'd be able to see the planet directly just as easily.
Our view of the sky is typically just a matter of seeing through little soda straws from one day to the next, so we miss a lot.
Noob question: Why isn't it passing in front of stars? Are we seeing a sequential dimming of occluded stars along the plane of the ecliptic?
My intuition suggests that a planet far out and small would be very difficult to detect by its occlusion. This page calculates that Pluto for instance spans only 3 pixels at the Hubble space telescopes resolution: http://www.planetary.org/blogs/emily-lakdawalla/2013/0214101...
The planet and the star can both be much smaller than a pixel, as long as the planet is big enough to cover the star.
This is awesome. Also I found a tiny nitpick "But the early 1990s also brought a big breakthrough in an algorithm, known as symplectic integration, that reduced computational times by an order of magnitude." then "Because symplectic integrators don’t waste time rediscovering Kepler’s laws over and over, they run orbital simulations hundreds of times as fast as older methods do." 100 times as fast is two orders of mag…
In base 10, 100x is 2 orders of magnitude.
In base 2, the same speed up (written in binary: 1100100x) is between 6 and 7 orders of magnitude.
Noob question: Why isn't it passing in front of stars? Are we seeing a sequential dimming of occluded stars along the plane of the ecliptic?
My intuition suggests that a planet far out and small would be very difficult to detect by its occlusion. This page calculates that Pluto for instance spans only 3 pixels at the Hubble space telescopes resolution: http://www.planetary.org/blogs/emily-lakdawalla/2013/0214101...
https://www.forbes.com/sites/startswithabang/2017/06/21/good...
As the months passed since it was first proposed by Konstantin Batygin and Mike Brown, they compiled additional evidence for it, and things were looking rosy. But a new study by Shankman et al. has turned the evidence on its head, disfavoring the planet's existence and uncovering a bias in the data itself.
https://arxiv.org/abs/1706.05348
"The clustered TNOs were detected across different and independent surveys, which has led to claims that the detections are therefore free of observational bias. This apparent clustering has led to the so-called "Planet 9" hypothesis that a super-Earth currently resides in the distant solar system and causes this clustering. The Outer Solar System Origins Survey (OSSOS) is a large program that ran on the Canada-France-Hawaii Telescope from 2013--2017, discovering more than 800 new TNOs. One of the primary design goals of OSSOS was the careful determination of observational biases that would manifest within the detected sample. We demonstrate the striking and non-intuitive biases that exist for the detection of TNOs with large semi-major axes. The eight large semi-major axis OSSOS detections are an independent dataset, of comparable size to the conglomerate samples used in previous studies. We conclude that the orbital distribution of the OSSOS sample is consistent with being detected from a uniform underlying angular distribution."
I hope I get to see some New Horizons-esque images of it by the time I'm old and grey. Imagine its moons. Does it have rings? Does it have Trojans? Is it another line of defence, a remote cosmic vacuum cleaner, like Jupiter? Maybe Clarke's monolith lurks in its orbit. I can't wait to find out.