Evan Gough, Author at Universe Today

August 4, 2020August 4, 2020 by Evan Gough

Microbes Were Dormant for Over 100 Million Years, But They Were Able to Spring Back to Life

Magnified image showing microbes revived from 101.5-million-year-old sediment. Image Credit:Japan Agency for Marine-Earth Science and Technology

At the bottom of the ocean in the South Pacific Gyre, there’s a sediment layer that is among the most nutrient-starved environments on Earth. Because of conditions in that area, there’s almost no “marine snow”—the shower of organic debris common in the ocean—that falls to the ocean floor. Without all that organic debris falling to the floor, there’s a severe lack of nutrients there, and that makes this one of the least hospitable places on Earth.

A team of researchers took sediment samples from that area, and extracted 101.5 million year old microbes. When they “fed” those microbes, they sprang back to life.

The results are expanding our knowledge of microbial life and how long it can be dormant when conditions force it to be.

July 31, 2020July 31, 2020 by Evan Gough

Ancient Meteorites Can be Found Embedded in Rocks, Like Fossils

Fossil meteorites from the mid-Ordovician period, around 460 million years ago, indicate that Earth may have been hit by debris from an asteroid collision at that time. Image credit - Birger Schmitz

Comets visit the inner Solar System, and leave without saying goodbye. Maybe they leave a trail of dust behind, and when the Earth passes through it, we get a pretty light show in the night sky, in the form of a meteor shower. Likewise, asteroids frequently go whizzing by, though they don’t leave us with a pyrotechnic display.

Sometimes these rocky interlopers head straight for Earth. And when they do, the results can be cataclysmic, like when an asteroid struck Earth about 66 million years ago, wiping out the dinosaurs and 75% of life on Earth. Other times, it’s not quite as cataclysmic, but still devastating, like in about 2350 BC, when debris from a disintegrating comet may have caused the collapse of an ancient empire.

But regardless of the severity of any of these individual events, the conclusion is crystal clear: Earth’s history is intertwined with the coming and going of space rocks. The evidence is all around us, sort of.

July 30, 2020July 30, 2020 by Evan Gough

Earth Observation Satellites Could be Flown Much Lower than Current Altitudes and Do Better Science

A satellite image of Tropical Depression Cristobal over the US. Image Credit: NASA Earth Observatory.

Satellite engineers know what every photographer knows: get close to your subject to get better pictures. Not just visible light pictures, but all across the spectrum. The lower altitude also improves things like radar, lidar, communications, and gps.

But when your subject is Earth, and Earth is surrounded by an atmosphere, getting closer is a delicate dance with physics. The closer a satellite gets to Earth, the more atmospheric drag it encounters. And that can mean an unscheduled plummet to destruction for Earth-Observing (EO) satellites.

July 29, 2020July 29, 2020 by Evan Gough

A Group of Meteorites All Came From a Destroyed Planetesimal With a Magnetic Core

Samples from a rare meteorite family, including the one shown here, reveal that their parent planetesimal, formed in the earliest stages of the solar system, was a complex, layered object, with a molten core and solid crust similar to Earth. Photo credit: Carl Agee, Institute of Meteoritics, University of New Mexico. Background edited by MIT News.

Before our Solar System had planets, it had planetesimals. Scientists think that most of the meteorites that have struck Earth are fragments of these planetesimals. Scientists also think that these planetesimals either melted completely, very early in their history, or that they remained as little more than collections of rocks, or “rubble piles.”

But one family of meteorites, that have been found spread around the world, appear to come from a planetesimal that bucked that trend.

July 28, 2020July 28, 2020 by Evan Gough

Russia Just Tested an Anti-Satellite Weapon

Orbital ATK Minotaur IV rocket streaks to orbit after blastoff carrying the ORS-5 space situational awareness and debris tracking satellite to orbit for the military at 2:04 a.m. EDT on August 26, 2017 from pad 46 on Cape Canaveral Air Force Station in Florida. Credit: Michael Seeley/WeReportSpace

The United States and Russia/USSR have been adversaries for a long time. Their heated rivarly stretches back to the waning days of WW2, when the enormous Red Army was occupying large swathes of eastern Europe, and the allies recognized the inherent threat.

The Cold War followed, when the two nations aimed an absurd number of nuclear warheads at each other. Then came the Space Race, when both nations vied for the prestige of making it to the Moon.

The US won that race, but the rivalry didn’t cool down.

July 28, 2020July 28, 2020 by Evan Gough

Here’s the New Space Force Logo

The US Space Force unveiled their new logo and motto. Image Credit: US Space Force

The newest branch of the US Military has a logo and a motto now. The mottos is Semper Supra, meaning ‘Always Above’. The logo’s main feature is a delta wing design.

July 28, 2020July 28, 2020 by Evan Gough

This is What an Air-Breathing Electric Thruster’s Intake Would Look Like

A drawing of an air intake collector for use on electric air thrusters on satellites. Image Credit: ESA/VKI/Politechnico di Milano

Like all other technologies, satellite technology has grown in leaps and bounds in the past couple decades. Satellites can monitor Earth in increasingly high resolutions, aiding everything from storm forecasting, to climate change monitoring, to predicting crop harvests. But there’s one thing still holding satellites back: altitude.

July 24, 2020July 24, 2020 by Evan Gough

What Cracked the Earth’s Outer Shell and Started its Plate Tectonics?

A snapshot of a model from the new work, showing the late stages of growth and coalescence of a new global fracture network. Fractures are in black / shadow, and colors show stresses (pink color denotes tensile stress, blue color denotes compressive stress). Image Credit: Tang et al, 2020.

Earth’s lithosphere is made up of seven large tectonic plates and a number of smaller ones. The theory of plate tectonics that describes how these plates move is about 50 years old. But there’s never really been an understanding of how this system developed, and how the Earth’s shell split into separate plates and started moving.

Now a group of researchers have a possible explanation.

July 24, 2020July 24, 2020 by Evan Gough

800 Million Years Ago, it Was Raining Asteroids on the Earth and Moon

An artist's illustration of an asteroid shower on the Earth-Moon system. Image Credit: Murayama/Osaka Univ.

Natural processes here on Earth continually re-shape the planet’s surface. Craters from ancient asteroid strikes are erased in a short period of time, in geological terms. So how can researchers understand Earth’s history, and how thoroughly it may have been pummeled by asteroid strikes?

Scientists can turn their attention to our ancient companion, the Moon.

July 23, 2020July 23, 2020 by Evan Gough

Dust Seen Streaming Out of Namibia Into the Atlantic Ocean

Landsat 8 strikes again.

Landsat 8 is the United States Geological Survey’s most recently launched satellite, and it holds the powerful Operational Land Imager (OLI.) The OLI is a powerful multi-spectral imager with a wide dynamic range.

The OLI does a great job of keeping an eye on Earth, and now its captured images of winds in Namibia picking dust up and carrying it out over the Atlantic Ocean.