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The Island Named After a Satellite

It is so small that you cannot see it on Google maps. It measures 25 by 45 meters (27 by 49 yards), about half the size of a football field. This barren bit of rock off the coast of Canada also has an unusual namesake: the Landsat 1 satellite. The small size is actually what made the island notable in 1973, when it was initially discovered. Well, that, and the polar bear trying to eat one of the surveyors.

Betty Fleming, a researcher with the Topographic Survey of Canada, was hunting for uncharted islands and rocks amidst data from the new Landsat 1 satellite. She was particularly interested in the new satellite's ability to find small features. Working with the Canadian Hydrographic Service, Fleming scanned images of the Labrador coast, an area that was poorly charted. About 20 kilometers (12 miles) offshore, the satellite detected a tiny, rocky island. Surveyors were sent to verify the existence of the island and encountered a hungry polar bear on the island. The surveyor quickly retreated. Eventually, the island became known as “Landsat Island,” after the satellite that discovered it. Watch the video to learn more about Betty Fleming and how Landsat Island was discovered by satellite and ground surveyors.

For more details about Landsat Island, read the full stories here:

The Island Named After a Satellite

The Unsung Woman Who Discovered an Unknown Island

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Our Planet: 8 Stunning Views of Earth from Space

Swirling clouds, deep blue oceans and textured land- and icescapes are among the many faces of our planet revealed in NASA’s new photo-essay book: Earth. This collection of 69 images captured by satellites tells a story of a 4.5-billion-year-old planet where there is always something new to see. Earth is a beautiful, awe-inspiring place, and it is the only world most of us will ever know. It is your planet. It is NASA’s mission. The book is available now in hardcover and ebook, and online with interactive features.

Here are eight of those breathtaking images for your viewing pleasure. 

Channel Country, Australia

These wide floodplains in Queensland, Australia are unique on the planet. Scientists think they are caused by the extreme variation in water and sediment discharges from the rivers. In many years there is no rainfall at all, and the rivers are effectively non-existent. In years of modest rainfall, the main channels will carry some water, sometimes spilling over into narrow water holes known as billabongs.

Every few decades, the floodplain carries extremely high discharges of water. For instance, tropical storms to the north can lead to great water flows that inundate the entire width of the floodplain. On such occasions, the floodplain appears as series of brown and green water surfaces with only tree tops indicating the location of the islands. Such is the case in this image taken from the International Space Station in September 2016.

Grounded in the Caspian, Kazakhstan

A wide variety of ice forms in the Caspian Sea, which stretches from Kazakhstan to Iran. Just offshore, a well-developed expanse of consolidated ice appears bright white. Farther offshore, a gray-white field of chunky, hummocked ice has detached and is slowly drifting around a polynya, an area of open water surrounded by sea ice. That darker patch is actually growing young, thin ice and nilas, a term that designates sea ice crust up to 10 centimeters (4 inches) in thickness.

The close-up shows nilas and a white, diamond-shaped piece of ice. It might look like this chunk is on the move, cutting a path through thinner ice. But it’s more likely that the “diamond” was stuck to the sea bottom and the wind pushed ice around it.

Tsauchab River Bed, Namibia

The Tsauchab River is a famous landmark for the people of Namibia and tourists. Yet few people have ever seen the river flowing with water. In December 2009, an astronaut on the International Space Station caught this glimpse of the Tsauchab River bed jutting into the sea of red dunes. It ends in a series of light-colored, silty mud holes on the dry lake floor.

Like several other rivers around the Namib Desert, the Tsauchab brings sediment down from the hinterland toward the coastal lowland. This sediment is then blown from the river beds, and over tens of millions of years it has accumulated as the red dunes of the Namib Sand Sea.

Taranaki and Egmont, New Zealand

The circular pattern of New Zealand’s Egmont National Park stands out from space as a human fingerprint on the landscape. The park protects the forested and snow-capped slopes around Mount Taranaki (Mount Egmont to British settlers). It was established in 1900, when officials drew a radius of 10 kilometers around the volcanic peak. The colors differentiate the protected forest (dark green) from once-forested pasturelands (light- and brown-green).

Named by the native Maori people, Taranaki stands 2,518 meters (8,260 feet) tall, and it is one of the world’s most symmetric volcanoes. It first became active about 135,000 years ago. By dating lava flows, geologists have figured out that small eruptions occur roughly every 90 years and major eruptions every 500 years. Landsat 8 acquired this image of Taranaki and the park in July 2014.

Storms Stir Up Sediment in Bermuda

In October 2014, the eye of Hurricane Gonzalo passed right over Bermuda. In the process, the potent storm stirred up the sediments in the shallow bays and lagoons around the island, spreading a huge mass of sediment across the North Atlantic Ocean. This Landsat 8 image shows the area after Gonzalo passed through.

The suspended sediments were likely a combination of beach sand and carbonate sediments from around the shallows and reefs. Coral reefs can produce large amounts of calcium carbonate, which stays on the reef flats (where there are coralline algae that also produce carbonate) and builds up over time to form islands.

Framing an Iceberg in the South Atlantic Ocean

In June 2016, the Suomi NPP satellite captured this image of various cloud formations in the South Atlantic Ocean. Note how low stratus clouds framed a hole over iceberg A-56 as it drifted across the sea.

The exact reason for the hole in the clouds is somewhat of a mystery. It could have formed by chance, although imagery from the days before and after this date suggest something else was at work. It could be that the relatively unobstructed path of the clouds over the ocean surface was interrupted by thermal instability created by the iceberg. In other words, if an obstacle is big enough, it can divert the low-level atmospheric flow of air around it, a phenomenon often caused by islands.

Lofted Over Land in Madagascar

Along the muddy Mania River, midday clouds form over the forested land but not the water. In the tropical rainforests of Madagascar, there is ample moisture for cloud formation. Sunlight heats the land all day, warming that moist air and causing it to rise high into the atmosphere until it cools and condenses into water droplets. Clouds generally form where air is ascending (over land in this case), but not where it is descending (over the river). Landsat 8 acquired this image in January 2015.

A Lava Lamp Look at the Atlantic Ocean 

Stretching from tropical Florida to the doorstep of Europe, the Gulf Stream carries a lot of heat, salt, and history. This river of water is an important part of the global ocean conveyor belt, moving water and heat from the Equator toward the far North Atlantic. It is one of the strongest currents on Earth and one of the most studied. Its discovery is often attributed to Benjamin Franklin, though sailors likely knew about the current long before they had a name for it.

This image shows a small portion of the Gulf Stream off of South Carolina as it appeared in infrared data collected by the Landsat 8 satellite in April 2013. Colors represent the energy—heat—being emitted by the water, with cooler temperatures in purple and the warmest water being nearly white. Note how the Gulf Stream is not a uniform band but instead has finer streams and pockets of warmer and colder water.

These images are just a few from our new book called Earth. Explore the other 61 images here.

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The Birth of a New Island

In late December 2014, an underwater volcano in the South Pacific Kingdom of Tonga erupted and sent a violent stream of steam, ash and rock into the air. The ash plumes rose as high as 30,000 feet (9 kilometers) into the sky and diverted airline flights.

Most new oceanic islands often wash away quickly within a few months. The island doesn't have an official name, and is referred to as Hunga Tonga-Hunga Ha'apai after two older islands to either side.

But this island was different. One of our satellites that detects volcanic eruptions alerted our scientists who were very excited because this type of explosive, undersea eruption is rare. In fact, the new Tongan island is one of only three of this kind of volcanic islands in the past 150 years to emerge and survive. It's now three years old.

Zooming in from Space

The baby island is also the first of its kind to emerge in the modern satellite era. This is really important since it's difficult to send our researchers the South Pacific every month to see how the island has changed – which it did very rapidly, especially in the first six months. But satellites in space delivered monthly views which we used to make these high resolution, 3-D topographic maps. With these maps, we tracked the early life and evolution of the island in unprecedented detail.

In April 2015, we watched an isthmus bridge begin forming from the new island to the older island neighboring it to the east. Soft volcanic material, especially on the island's southern side, was eroded by the ocean and deposited on the tail end, which grew and grew till it reached the other island. It's about 1600 feet (500 meters) across, or the length of 5 football fields.

The erosive forces of the ocean broke down the southern wall of the crater lake in May 2015. We thought this might mean that the island wouldn't last much longer because the ocean could now attack the interior of the island's tuff cone. But in June, a sandbar formed, closing off the lake again and protecting the interior. The sandbar has been in place ever since.

Monitoring these changes of both erosion and growth, we now believe that the island will last from between 6 to 30 years!

Terranauts!

Why has the island survived for three years? What makes eroding it away harder than for other blink-and-you-miss-it oceanic islands that disappear into the sea after a few months? To answer these questions, we need rock samples.

Working with the Tongan government, we recruited two French citizens sailing around the world who were in Tongan waters in June, 2017, to go to the new island on our behalf. We treated them like astronauts and gave them instructions to take pictures and samples of the volcanic rocks at locations we could see from space along the coasts, the interior of the crater lake, and from the top of the tuff cone.

They did a fantastic job documenting each sample and where it came from, and then mailed the box of rocks back to our team at our Goddard Space Flight Center in Greenbelt, Maryland, where they are currently being analyzed. We believe that after the eruption, warm seawater mixed with volcanic ash to chemically alter it so that when it hardened into rock it was a tougher material. We're excited to see if the rock samples confirm this.

From Earth to Mars

Link: https://svs.gsfc.nasa.gov/11372

Did these Martian volcanoes form in an ocean or lake? If they did, wet environments such as these combined with heat from volcanic processes may be prime locations to search for evidence of past life. We may not know until we arrive on the red planet, but by studying Earth's landforms, we'll be better prepared when we do.

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