The instrument, called HI-C for High Resolution Coronal Imager, will fly aboard a Black Brant sounding rocket to be launched from the White Sands Missile Range in New Mexico. The mission will have just 620 seconds for its flight, spending about half of that time high enough that Earth's atmosphere will not block ultraviolet rays from the sun. By looking at a specific range of UV light, HI-C scientists hope to observe fundamental structures on the sun, as narrow as 100 miles across.
Waiting for launch: NASA's HI-C mission, sitting in the front of this image, will launch on July 11, 2012, to observe the sun's corona in the highest detail ever captured during a 381-second flight. Credit: NASA
"Other instruments in space can't resolve things that small, but they do suggest – after detailed computer analysis of the amount of light in any given pixel – that structures in the sun's atmosphere are about 100 miles across," says Jonathan Cirtain, a solar scientist at NASA's Marshall Space Flight Center in Huntsville, Ala. who is the project scientist for HI-C. "And we also have theories about the shapes of structures in the atmosphere, or corona, that expect that size. HI-C will be the first chance we have to see them."
The spatial resolution on HI-C is some five times more detailed than the Atmospheric Imaging Assembly (AIA) instrument on the Solar Dynamics Observatory (SDO), that can resolve structures down to 600 miles and currently sends back some of our most stunning and scientifically useful images of the sun. Of course, AIA can see the entire sun at this resolution, while HI-C will focus on an area just one-sixth the width of the sun or 135,000 miles across. Also, AIA observes the sun in ten different wavelengths, while HI-C will observe just one: 193 Angstroms. This wavelength of UV light corresponds to material in the sun at temperatures of 1.5 million Kelvin and that wavelength is typically used to observe material in the corona.
During its ten-minute journey, HI-C will focus on the center of the sun, where a large sunspot is predicted to be – a prediction based on what the sun looked like 27 days previously, since it takes 27 days for the sun to complete a full rotation.
"We will start acquiring data at 69 seconds after launch, at a rate of roughly an image a second," says Cirtain. "We will be able to look through a secondary H-alpha telescope on the instrument in real time and re-point the main telescope as needed."
In addition to seeing the finest structures yet seen in the sun's corona, the launch of HI-C will serve as a test bed for this high-resolution telescope. Often one improves telescope resolution simply by building bigger mirrors, but this is not possible when constraining a telescope to the size of a sounding rocket, or even a long-term satellite. So HI-C's mirror is only about nine and a half inches across, no bigger than that of AIA. However, the HI-C mirrors, made by a team at Marshall, are some of the finest ever made, says Cirtain. If one could see the surface at an atomic level, it would show no greater valleys or peaks than two atoms in either direction.
"So it's super smooth," says Cirtain.
In addition, the team created a longer focal length – that is, they increased the distance the light travels from its primary mirror to its secondary mirror, another trick to improve resolution – by creating a precise inner maze for the light to travel from mirror to mirror, rather than a simple, shorter straight line.
NASA's Marshall Space Flight Center is leading the international effort for Hi-C. Key partners include the University of Alabama at Huntsville, Smithsonian Astrophysical Observatory, University of Central Lancashire in Lancashire, England, and the Lebedev Physical Institute of the Russian Academy of Sciences.
Karen Fox | EurekAlert!
Levitating objects with light
19.03.2019 | California Institute of Technology
19.03.2019 | Leibniz-Institut für Astrophysik Potsdam
Due to the special arrangement of its molecules, a new coating made of corn starch is able to repair small scratches by itself through heat: The cross-linking via ring-shaped molecules makes the material mobile, so that it compensates for the scratches and these disappear again.
Superficial micro-scratches on the car body or on other high-gloss surfaces are harmless, but annoying. Especially in the luxury segment such surfaces are...
The Potsdam Echelle Polarimetric and Spectroscopic Instrument (PEPSI) at the Large Binocular Telescope (LBT) in Arizona released its first image of the surface magnetic field of another star. In a paper in the European journal Astronomy & Astrophysics, the PEPSI team presents a Zeeman- Doppler-Image of the surface of the magnetically active star II Pegasi.
A special technique allows astronomers to resolve the surfaces of faraway stars. Those are otherwise only seen as point sources, even in the largest telescopes...
Researchers at Chalmers University of Technology and the University of Gothenburg, Sweden, have proposed a way to create a completely new source of radiation. Ultra-intense light pulses consist of the motion of a single wave and can be described as a tsunami of light. The strong wave can be used to study interactions between matter and light in a unique way. Their research is now published in the scientific journal Physical Review Letters.
"This source of radiation lets us look at reality through a new angle - it is like twisting a mirror and discovering something completely different," says...
New research group at the University of Jena combines theory and experiment to demonstrate for the first time certain physical processes in a quantum vacuum
For most people, a vacuum is an empty space. Quantum physics, on the other hand, assumes that even in this lowest-energy state, particles and antiparticles...
Physicists in the EPic Lab at University of Sussex make crucial development in global race to develop a portable atomic clock
Scientists in the Emergent Photonics Lab (EPic Lab) at the University of Sussex have made a breakthrough to a crucial element of an atomic clock - devices...
11.03.2019 | Event News
01.03.2019 | Event News
28.02.2019 | Event News
20.03.2019 | Life Sciences
20.03.2019 | Life Sciences
20.03.2019 | Trade Fair News