That's an awfully small chunk ...
... an awfully long way away, found by a very few folks, with almost zero money.
Well done, OASES! This round's on me :-)
A plucky group of low-budget astronomers has pulled off quite a coup by spotting the smallest object yet in the Kuiper Belt, the donut of icy objects swirling around in the outer Solar System. Amazingly, the OASES (Organized Autotelescopes for Serendipitous Event Survey) team made the find using a pair of small 28cm (11-inch …
Two 11" telescopes plus the required hardware (mounts, guide, cameras, etc.) is not exactly something you get with "almost zero money". Depending on which telescopes and hardware they used, you can easily run into several thousands. Sure, still a tiny fraction of bigger projects, but from an amateur point of view, still a not-so-cheap project - unless your pockets are quite deep.
It's still impressive today thanks to digital imaging and processing you can do good science with "low end" kits, despite the availability of gigantic and orbital telescopes.
Update: a quick check tells me that the astrographs alone costs over 4K, and the cameras 1.5K each - dont't Japaneses prices, but it's 11K only for the main pieces.
Not amateurs but a research team led by Ko Arimatsu at the National Astronomical Observatory of Japan. But still, as you say, outstanding work and bloody brilliance to work out that "big science" can sometimes be extrapolated down to "petty cash account science" and still come up with big results.
"The Solar System is full of tiny bits of debris leftover from the swirling protoplanetary disk that formed around our young Sun billions of years ago. Only a small proportion of these dusty particles managed to clump together to form planets."
No, almost all of it has "clumped together".
"The principal component of the Solar System is the Sun, a G2 main-sequence star that contains 99.86% of the system's known mass and dominates it gravitationally. The Sun's four largest orbiting bodies, the giant planets, account for 99% of the remaining mass, with Jupiter and Saturn together comprising more than 90%. The remaining objects of the Solar System (including the four terrestrial planets, the dwarf planets, moons, asteroids, and comets) together comprise less than 0.002% of the Solar System's total mass."
"The mass of the Solar System excluding the Sun, Jupiter and Saturn can be determined by adding together all the calculated masses for its largest objects and using rough calculations for the masses of the Oort cloud (estimated at roughly 3 Earth masses), the Kuiper belt (estimated at roughly 0.1 Earth mass) and the asteroid belt (estimated to be 0.0005 Earth mass) for a total, rounded upwards, of ~37 Earth masses, or 8.1% of the mass in orbit around the Sun. With the combined masses of Uranus and Neptune (~31 Earth masses) subtracted, the remaining ~6 Earth masses of material comprise 1.3% of the total orbiting mass."
The Sun is not a planet.
Careful now. The last time someone declared something was not a planet it triggered an enormous row. Although I think you're probably safe with 'the Sun is not a planet' unless you encounter a particularly belligerent and argumentative astronomer :)
AFAIK orbital parameters of some comets are an evidence they should come from something alike the Oort Cloud, but I don't think we've ever observed something in a "stable" orbit at those distances. Those bodies should be orbiting very slow, and their angular size will be tiny as well - unless there's something quite big lurking there.
"Does he mean we never observed an object in the Oort Cloud, yet we know it exists?"
Pretty much. We know that starbirth is likely to produce a loose 'shell' of gravitational objects within a region beyond the planetary system, and that there is evidence of orbital perturbation on comets that enter the inner system.
It's rather like the early part of the 20th Century, when astronomers were looking for a 9th planet, which had never been spotted but was obviously there based on its gravitational effects.
Unless someone can point out the groundbreaking new technique that enabled them to make this discovery, I'm inclined to chalk this one up to "bothering to show up in the first place" and then getting ridiculously lucky. Which, admittedly, is still very much respectable and nothing to sneeze at, but far short of the fabulous amount of credit apparently both offered and taken. If they did do something radically differently, by all means, do correct me...
From what I read, no "groundbreaking" new technique but a clever use of existing ones to look at many stars in a single image. They got wide-field astrographs able to cover a larger format sensor, then used a focal reducer (often called "speed booster" in the photography) to project that field on a smaller sensor - improving that way the faintest stars level they can analyze. There are also some interesting techniques to "sync" data from the two telescopes. It would be interesting to know how they reduced data, how much processing power was needed and how long it takes.
Correctly, they hoped in some serendipity from the very beginning, looking at the project name - anyway they got repaid if they got an interesting even with 60 hours of data only.
"We also have our sights set on the still undiscovered Oort Cloud out beyond that"
If the method of detection is seeing the dimming of a start as another object passes in front of it how can the distance of the object be determined? I appreciate that a more distant object will result in a smaller dip but so will a smaller, closer object.
I'm guessing the precise timing ( using meteors - very clever ! ) and separation of the scopes allows triangulation?
"...In addition, a precise time synchronization method needed for simultaneous occultation detection is developed using faint meteors..."
They don't have much separation as they're on a small island - only a few km across. Their sampling rate is only 15.4 Hz. I suppose, however, they could extend to a bigger baseline having proved the system but a continent sized baseline would need something other than faint meteors to synchronize.
It's cold and clear out (hardly fresh news, i know). Cycling along the cycleway i looked up to marvel at the starlit heavens. Followed almost immediately by a massive reduction in luminosity.
More accurately, a total loss of visibility as my breath froze within my specs.
with all that debris out there, I wouldn't want to chance bumping into one of those
Head out in the same direction as the sun's spin axis and you should avoid most of the debris.
You might hit something in the Oort Cloud still though.
Anyway, the finest astronomers of Earth have prepared this map for you. If you could just fill it in as you go along they'd be ever so grateful ...
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