Radar Data Yields High-Resolution Views of Near-Earth Asteroid HQ124 29
On June 8th, with a radio source beamed at the asteroid designated 2014 HQ124 (less formally, "the beast") while two other telescopes tracked that beam's reflections, NASA was able to gather high-quality images of the object as it zipped by a mere 776,000 miles from Earth. (Some asteroids are closer, and a vast number of them could soon be better known, but none have allowed as good an opportunity for radar obvservation.) Astronomy Magazine's account adds a bit more detail: To obtain the new views, researchers paired the 230-foot (70m) Deep Space Network antenna at Goldstone, California, with two other radio telescopes, one at a time. Using this technique, the Goldstone antenna beams a radar signal at an asteroid and the other antenna receives the reflections. The technique dramatically improves the amount of detail that can be seen in radar images.
To image 2014 HQ124, the researchers first paired the large Goldstone antenna with the 1,000-foot (305m) Arecibo radio telescope in Puerto Rico. They later paired the large Goldstone dish with a smaller companion, a 112-foot (34m) antenna, located about 20 miles (32km) away.
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The first five images in the new sequence — the top row in the collage — represent the data collected by Arecibo and are 30 times brighter than what Goldstone can produce observing on its own.
Requisite (Score:5, Funny)
Re:Requisite (Score:5, Funny)
Praise the Lord in his infinite wisdom for giving us minds with which to appreciate the splendour of his creation. ...is what I think you meant to say.
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Re: (Score:2)
Well, you may laugh about that, but in the past that is exactly what happened, and we try to cover it up now in scientific circles.
It took a religious liberation to stop people to adhere to ancient texts that could only be interpreted by priests. People started looking for the Creator by investigating the creation. This religiously motivated search has added tremendously to science. For example, the Frederik Ruysch collection in the KunstKammer in St Petersburg is from that period.
Alas, we like to think tha
High resolution (Score:2, Insightful)
The imaging technique can pick up features as small as 12 feet, on a 1200 foot long asteeroid
So thats about 100 pixels
Not exactly todays definition of high resolution when new tablets are coming out with 2560 x 1600 pixels
Re: (Score:2, Informative)
you're missing the point of how far away the object scanned is. It would be quite small in degrees -> very high resolution is needed to scan it.
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Not exactly todays definition of high resolution when new tablets are coming out with 2560 x 1600 pixels
How large does it appear on said tablet? Go ahead, take a better photo!
It's almost like people think the "zoom and enhance" of some f'ed up TV show is how reality works.
Re:High resolution (Score:4, Insightful)
Re: (Score:2, Insightful)
We have photos (optical photos) of Pluto is 18 pixels across, and it is 4.2 billion km away, versus the 1.2 million km that this asteroid is. Relative sizes of the two at this distance in terms of angular resolution are about equal, so the thought that we could get something that is roughly 6x the quality by augmenting conventional imaging technologies with active radio bombardment is pretty spectacular.
Re: High resolution (Score:3)
The term "resolution" predates raster images, and thus it means more than "pixel count":
Optical resolutionÂdescribes the ability of an imaging e system to resolve detail in the object that is being imaged.
http://en.wikipedia.org/wiki/O... [wikipedia.org]
Re: High resolution (Score:2)
The term "resolution" predates raster images, and thus it means more than "pixel count":
Optical resolutionÂdescribes the ability of an imaging e system to resolve detail in the object that is being imaged.
http://en.wikipedia.org/wiki/O... [wikipedia.org]
Re: (Score:1)
Re: (Score:1)
The imaging technique can pick up features as small as 12 feet, on a 1200 foot long asteeroid
So thats about 100 pixels
Not exactly todays definition of high resolution when new tablets are coming out with 2560 x 1600 pixels
Well, on that display the entire asteroid would be less than one pixel. So calculate for me the resolution that would mean for the zoomed pictures in the article!
According to the article... (Score:2)
I wasn't aware that a Teletubby was a standard unit of comparison. Maybe Le Système international d'unités can define degrees of similarity... "That asteroid is .7 Teletubbies in shape!"
I wonder what the SI unit for Teletubbies would be...
So, how far was it in relative terms? (Score:4, Informative)
Giving the 776,000 miles number is of little value for most people. Comparing it to 1 Astronomical Unit (the average distance Earth-Sun = 92,955,807.3 miles) or the distance between the Earth & the moon (238,857 miles) makes it much more understandable.
Given that these infos are informative & not biased, I can see how Timothy didn't think to add them to the summary.
Re: (Score:2)
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So, without the numbers I gave you were able to tell that the asteroid was imaged at just over three times the distance the moon you look up to in the sky is? Well, no because you certainly didn't know that because the people who do don't use the distance they have traveled on earth as a reference.
Did the raw number give you enough information to know how far into the earth's gravity well it was? Or even whether it had entered it? Nope, you didn't know that either.
Oh, but 776 times 1000 times 63360 inches,
Why didn't it hit earth? (Score:3, Funny)
There's also video of them successfully deflecting the asteroid: https://www.youtube.com/watch?... [youtube.com]
New geometric unit of measurement? (Score:2)
NASA announced today that the latest geometric unit of measurement is the Teletubby. It will augment the square, rectangle, circle and oval.
I destroyed hundreds of these in my youth... (Score:2)
Re: (Score:2)
and at only $0.25 for three ships, it was a bargain. The ship even had hyperdrive!
But did you manage to beat the scores of ASS and FUK? Or are you either ASS or FUK?
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deep-space 'flash' pictures... (Score:2)
Although, it seems to me that -- if they had used both recieving dishes at the same time, we might have gotten some useful stereo images. Why didn't they do that?
Video Needs Sound (Score:2)
While checking out the video, I found myself realizing that it needed a soundtrack added. In particular, they should have added the sound effects from the original arcade version of Asteroids. That would have been awesome, and those forever top Asteroids champs ASS and FUK would have been so proud.
Why is it lit from the side? (Score:1)
The article says that these images are produced from radar scans. Why, then, does the asteroid look like it's illuminated from the side? If the asteroid was "illuminated" with a radar beam from an earth-based antenna, while the reflected radar waves were also detected using earth-based dishes, then shouldn't the asteroid look like it's illuminated head-on? Am I missing something here?
I worked on the project back in '68 (Score:4, Informative)
Back in ny early days as a lab techie I was running the optical processor that did the image-making post-processing for what I believe was the first "flyby" / "rotating target" synthetic aperture radar. (No significant intellectual contributions: I was running the machinery, rather than contributing to its design. Adjusting lenses, exposing and developing film, etc.)
Back in those days the computers weren't up to the amount of crunch needed. (This technique is essentially a two-dimensional fourrier transform with tweaks.) So we used laser light and lenses for the fourier transform, and photographic film for the input modulation and output capture. The original data was captured using a one-dimensional CRT with a solid row of fiber-optic light-pipes built into the faceplate. This was in actual contact with the recording film, transferrig the light from the phosphor inside the CRT without geometric distortions from lenses and such. The film was about four inches wide, and the servo capstain that advanced it was a critical component for accurate signal processing, as was the circuitry that linearized the sweep of the beam. The input plane of the optic processor held the film in a xylene solution between two optical flats, to eliminate phase distortion from roughness of the film's surface.
The nice thing about synthetic aperture radar is that the resolution is related to the radar frequencies and the relative motion of the antenna(s) and target, and is not dependent on the beam width of the antenna. (Well, wider beam width means you illuminate the target from a larger virtual antenna, sharpening the image.) Except for deltas, distance doesn't matter, either. You get the same resolution at tens of feet or interplanetary distances. Distance only comes into the pricture in terms of keeping the oscillators from drifting during the transit time of the beam, so you don't introduce varyimg phase errors when down-converting successive returned chirps.