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25 March 2014

Rapid response to natural disaster: ESA Sentinel-1 will launch new capability

Next week, on 3 April, a new era will begin in remote-sensing-aided disaster response. The European Space Agency (ESA) has announced that the Sentinel-1A radar satellite will be launched from the European spaceport in French Guiana.

Sentinel-1, the first in the family of
Copernicus satellites, will be used to
care for many aspects of our environment,
from detecting and tracking oil spills and
mapping sea ice to monitoring movement
in land surfaces and mapping changes in
the way land is used. It will also play a
crucial role in providing timely information
to help respond to natural disasters and
assist in emergency response. Photo:
ESA/ATG media lab
Sentinel-1 is designed for responding rapidly to aid emergencies and disasters such as flooding and earthquakes. The first satellite carries an advanced radar sensor to image Earth’s surface through cloud and rain and regardless of time of day.

Each Sentinel mission is based on a constellation of two satellites to provide robust datasets for Copernicus Services, the new name for the Global Monitoring for Environment and Security program, previously known as GMES.

The initiative is headed by the European Commission in partnership with the European Space Agency (ESA). It will provide accurate, timely and easily accessible information to improve the management of the environment, understand and mitigate the effects of climate change and ensure civil security. The first of the initial two-satellite mission, Sentinel-1A will be joined in orbit next year by Sentinel-1B.

Sentinel-1 carries a 12 m-long advanced synthetic aperture radar (SAR), working in C-band. Radar data can be used for monitoring land deformation. The “radar interferometry'” remote-sensing technique combines two or more radar images over the same area to detect changes occurring between acquisitions. Interferometry allows for the monitoring of even slight ground movement – down to a few mm – across wide areas.

As well as being a valuable resource for urban planners, this type of information is essential for monitoring shifts from earthquakes, landslides, and volcanic uplift.

Sentinel-1A being prepared for launch at
Europe’s spaceport in Kourou, French
Guiana. Photo: ESA-B v/d Elst
ESA is developing five families of Sentinel missions specifically for Copernicus. The Sentinels will provide a unique set of observations, starting with the all-weather, day and night radar images from Sentinel-1 to be used for land and ocean services.

Sentinel-2 will deliver high-resolution optical images for land services and Sentinel-3 will provide data for services relevant to the ocean and land.

Sentinel-4 and Sentinel-5 will provide data for atmospheric composition monitoring from geostationary and polar orbits, respectively.

SPIE Proceedings have reported extensively on instrumentation developed for the Sentinel missions, including 14 new papers published in November 2013 from conferences on Earth Observing Systems; Remote Sensing for Agriculture, Ecosystems, and Hydrology; Sensors, Systems, and Next-Generation Satellites; and SAR (Synthetic Aperture Radar) Image Analysis, Modeling, and Techniques.

ESA's Portal will cover the launch live, providing the videostream and updates of the launch at: www.esa.int/esalive and www.livestream.com/eurospaceagency.

20 March 2014

Colonoscopy: photonics at work, saving lives

What photonics enables the clinician to see: Fig. 2 H&E
histology, OCT B-scan images, and three-dimensional
(3-D)OCT volume render for (a–c) rectal and (d–f)
duodenal biopsies. Bar=0.2  mm. From “Spatially resolved
optical and ultrastructural properties of colorectal and
pancreatic field carcinogenesis observed by inverse
spectroscopic optical coherence tomography,” Journal
of Biomedical Optics
19(3), 036013 (Mar 18, 2014).
Having a colonoscopy? If you're 50 or older, is there really a question?

No question at all -- if you have the means to go in for a colonoscopy, do so. The optics-and-photonics-enabled technology could save your life.

So say the results of recent research into the effectiveness of the endoscopic inspection of the colon as a means of detecting and removing cancerous or potentially dangerous growths, reports optics.org on an analysis of clinic data from the American Cancer Society (ACS).

In the USA, say ACS authors in the journal CA, colorectal cancer is the third most common cancer and the third leading cause of death from cancer.

As with all cancers, early detection is key.

The colonoscopy -- employing an external light source, fiber optics to carry light and data, a lens system, and imaging software and hardware -- offers the advantage of both detecting and potentially preventing cancer, via the removal of polyps.

The ACS paper is one of several recent reports illustrating the effectiveness of the procedure -- and the technology is improving all the time.

An article in The Lancet Oncology on results of trials by EndoChoice in Israel, the Netherlands, and the USA, reports that a new full-spectrum endoscopy was far more effective at detecting adenomas – non-cancerous growths that may become malignant or cancers.

At SPIE meetings earlier this year, conferences included reports on innovative next-generation imaging and modeling techniques and technology, such as the use of 3D and optical coherence tomography (OCT) methods to enhance accuracy, speed, and effectiveness of colonoscopy.

A paper from SPIE Medical Imaging by authors from the Massaschusetts Institute of Technology published earlier this week in the SPIE Digital Library describes a new software platform for high-performance 3D medical imaging processing. The paper was only one of many reporting on new techniques and technologies to improve cancer screening.

The BiOS symposium at Photonics West includes organizers and presenters representing the pioneers and the avant-garde in the field, with tracks on spectroscopy, microscopy, imaging, and nano/biophotonics all contributing to new and improved ways to detect and treat cancer and save more lives.

And an open access article published this week in the Journal of Biomedical Optics details a study on using OCT to improve analysis of changes in cells such as those in the digestive tract and colon that are susceptible to cancer. The work was done by researchers from Northwestern University, NorthShore University Health Systems, and Boston Medical Center.

The ACS report shows that more people in the USA are being screened and that death rates from colorectal cancer have declined in recent years. In the compelling words of the ACS’s Richard Wender, “These continuing drops in incidence and mortality show the lifesaving potential of colon cancer screening" -- enabled by optics and photonics.