NASA MESSENGER: False-Colour Image of Earth Highlights Plant Growth

On Aug. 3, 2004, NASA’s Mercury Surface, Space Environment, Geochemistry, and Ranging (MESSENGER) spacecraft began a seven-year journey, spiraling through the inner solar system to Mercury. 

One year after launch, the spacecraft zipped around Earth, getting an orbit correction from Earth’s gravity and getting a chance to test its instruments by observing its home planet.

Credit: NASA /Johns Hopkins University Applied Physics Laboratory /Carnegie Institution of Washington

This image is a view of South America and portions of North America and Africa from the Mercury Dual Imaging System’s (MDIS) wide-angle camera aboard MESSENGER.

MDIS, records light at eleven different wavelengths, including visible and infrared light. Combining blue, red, and green light results in a true-colour image from the observations.

The image substitutes infrared light for blue light in the three-band combination.

The resulting image is crisper than the natural colour version because our atmosphere scatters blue light.

Infrared light, however, passes through the atmosphere with relatively little scattering and allows a clearer view. That wavelength substitution makes plants appear red. Why?

Plants reflect near-infrared light more strongly than either red or green, and in this band combination, near-infrared is assigned to look red.

Apart from getting a clearer image, the substitution reveals more information than natural colour.

Healthy plants reflect more near-infrared light than stressed plants, so bright red indicates dense, growing foliage.

For this reason, biologists and ecologists occasionally use infrared cameras to photograph forests.

News Gathering Drone use highlights questions for journalists

In this March 2012 photo provided by the University of Missouri, in Columbia, Mo., is a DJI 550 drone with an attached camera mount that the university says is probably the model it will file for permission to use. 

The FAA is developing new rules as the technology makes drones far more versatile, but for now operators can run afoul of regulations by using them for commercial purposes, including journalism. 

AP Photo /University of Missouri, Zach Garcia

As police responded to a deadly car crash, they noticed an increasingly familiar sight: a remote-controlled aircraft, equipped with a video camera, hovering over the wreckage.

The Federal Aviation Administration (FAA) has opened an investigation of the drone, which was used by an on-call employee for a Connecticut television station.

The FAA is developing new rules as the technology makes drones far more versatile, but for now operators can run afoul of regulations by using them for commercial purposes, including journalism.

The case of the Hartford crash, in which the victim's body was left hanging out of a mangled car, highlights some of the safety, privacy and ethical issues that journalists will wrestle with as interest grows in using drones for news gathering.

"Here was a dead body still on the scene. We had covered it the best we could," said Lt. Brian Foley, a Hartford police spokesman, who said drones have been appearing more frequently at crime scenes. "You don't want the family to see that."

Hartford officers questioned the man operating the drone on Feb. 1 but did not ask him to take it down, Foley said. The man identified himself as an employee of WFSB-TV but said he was not working for them that day.

The station's general manager, Klarn DePalma, said it constantly evaluates new technology and is eager to see regulations spelled out for drones, but he said the temporary employee in question was not on assignment for them and has never been paid for drone video.

"We don't even own a drone," he said.

Aerial drones, long associated with the military, increasingly have been adapted for civilian use. They have been deployed widely to document the scale of disasters and, at the Sochi Olympics, they are being used to help broadcast the events.

Media outside the United States have been using drones in news coverage, including news organizations in Thailand covering political protests in Bangkok over the past three months.

In the U.S., the FAA said Monday that it has issued 12 warning letters to drone operators, which can include orders to stop operations. It said in a statement that its investigations are intended to determine whether operators violated FAA safety regulations.

A law passed by Congress two years ago requires the FAA to integrate unmanned aircraft of all sizes into the domestic airspace by late 2015, but it's clear the agency won't meet that deadline.

The FAA has been working for more than four years on regulations to permit small drones - those weighing less than 55 pounds - to be used for commercial purposes, but it has missed deadline after deadline for proposing those regulations.