Tag Archives: remote sensing

What Holds Dead Galaxies Together?

Seven to 10 billion years ago, a bunch of galaxies fell in with a bad crowd at the Coma cluster — a galactic group comprising thousands of their ilk. That crash “quenched” the ill-fated galaxies. They’d never again burn with hot, young stars. But the crash should have done more than shut down the unfortunate galaxies’ stellar birth rate. It should have strewn their stars across space.

So what kept these cosmic corpses intact? Read on, if you dare (OK, so the title is a bit of a hint …).

Dead Galaxies Indebted to Dark Matter

The James Webb Space Telescope Prepares to Peer Past Hubble

Artist's rendering of JWST
Artist’s rendering. Image courtesy NASA.

For two decades, the Earth-orbiting Hubble Space Telescope helped pierce the veil of time, image stellar nurseries and prove that galaxies collide. Now, the James Webb Space Telescope stands poised to take those observations to the next level, making the delicate observations possible only in the cold, dark spaces beyond the moon.

Slated for a 2018 launch date and team-built by 14 countries, 27 states and the District of Columbia, Webb will take astronomers closer to the beginning of time than ever before, granting glimpses of sights long hypothesized but never seen, from the birth of galaxies to light from the very first stars. Join us as we explore…

How the James Webb Space Telescope Will Work

Mars in a Nutshell

Think you know everything about Mars. eh?

We live in a golden age of Mars exploration, an era of unprecedented knowledge brought to us by ingenious rovers and probes. Already we have learned that our diminutive neighbor once held water and perhaps life. Future missions will help determine where that water went and seek evidence deep beneath the surface of living creatures. One day, we might even go there ourselves. But how much have you kept up on the latest developments?

How Mars Works

Tracking 2013’s Tastiest Tech

Detail of Google Glass
Photo by Antonio Zugaldia

Looking back on the tech trends, triumphs and tribulation of 2013, a few patterns emerge: Private projects took off even while privacy took a beating; robots and AI servants made great strides while their drone cousins stalked us with cameras and weapons; reality was simultaneously augmented and scrutinized, while 3-D-printing and private-sector space races seemingly brought the whole world into the realm of DIY.

2013’s Biggest Tech Moments

Starlight, star bright, first shot I snap tonight

Infrared photo of Webster's Falls
Photo: Marcus Qwertyus/Wiki Commons

Photography is all about light; it’s right there in the name: photo (“light”) + graph (“means of recording”). So how do you shoot in the gloom between the golden hours? Well, you have a few options. You can pop in a flashbulb. You can try your hand at painting with light – that is, fiddling with f-stops and shutter speeds to let more light in over a longer period. Unfortunately, flashbulbs tend to wash out photos, and setting up longer exposures tends to limit your photographic freedom.

Night-vision cameras and attachments get around these problems, either by amplifying existing light or working with a different kind of ambient “light” – aka infrared radiation, either from body heat (thermal IR) or from an active IR illuminator attached to the camera. Today, infrared and ultraviolet cameras also make useful tools for inspections and field work. But how do they work, and what is their history?

How Night-vision Cameras Work