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Mars is bright! Here’s why

Earth will between between the sun and Mars on May 22, 2016.  Then, the distance between our two worlds will be at its least for this two-year period, and Mars will appear brightest in our sky.  Image via Fourmilab.

Earth will pass between between the sun and Mars on May 22, 2016. Then, the distance between our two worlds will be at its least for this two-year period, and Mars will appear brightest in our sky. Image via Fourmilab.

We’re beginning to get questions about that red “star” in the east each evening. It’s Mars! We’ll pass between Mars and the sun this weekend.

How Earth’s magnetic field is changing

The magnetic field is thought to be largely generated by an ocean of superheated, swirling liquid iron that makes up Earth’s the outer core 3000 km under our feet. Acting like the spinning conductor in a bicycle dynamo, it generates electrical currents and thus the continuously changing electromagnetic field. Other sources of magnetism come from minerals in Earth’s mantle and crust, while the ionosphere, magnetosphere and oceans also play a role. ESA’s constellation of three Swarm satellites is designed to identify and measure precisely these different magnetic signals. This will lead to new insight into many natural processes, from those occurring deep inside the planet, to weather in space caused by solar activity.

Artist’s concept of ESA’s constellation of three Swarm satellites, designed to identify and measure the various magnetic signals from Earth. Image via ESA.

Data from a trio of satellites show rapid local changes in Earth’s magnetic field and link the changes to accelerations in the flow of liquid iron near Earth’s core. See two animations illustrating the changes, inside.

When will 2007 OR10 get a name?

Artist's concept of 2007 OR10, aka Snow White. It may have a rosy color, due to the presence of irradiated methane. Image via NASA.

Artist’s concept of 2007 OR10, whose original nickname was Snow White. It might have a rosy color, due to methane ices on its surface. Image via NASA.

2007 OR10 is now known as the third-largest dwarf planet. It’s about a third smaller than Pluto. It’s the largest unnamed body in our solar system.

News about mystery star KIC 8462852

Artist's concept of cascading comets around a distant star. This scenario is one possible explanation for mystery star  KIC 8462852. Image via NASA/JPL/Caltech/Vanderbilt University.

Artist’s concept of cascading comets around a distant star. This scenario is one of several possible explanations proposed for mystery star KIC 8462852. Image via NASA/JPL/Caltech/Vanderbilt University.

Astronomers at Vanderbilt and Louisiana State University disagree on the subject of whether mystery star KIC 8462852 – aka Tabby’s Star – has decreased in brightness by 20 percent over the past century.

Do you have friggatriskaidekaphobia?

Scared of Friday the 13th? An irrational fear of this date is called friggatriskaidekaphobia (Frigga is the Norse goddess for whom Friday is named). Image via Kelli Marshall

Scared of Friday the 13th? An irrational fear of this date is called friggatriskaidekaphobia (Frigga is the Norse goddess for whom Friday is named). Image via Kelli Marshall

May 13, 2016 is a Friday, ushering this year’s lone Friday the 13th. Every year has at least one Friday the 13th; and depending on the year, there can be two Friday the 13ths or a maximum of three Friday the 13ths. For example, last year, in 2015, there were three Friday the 13ths (February, March and November), and next year, in 2017, there will be two Friday the 13ths (January and October).

Old under-ice volcanoes on Mars

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This is the Sisyphi Montes region on Mars. Although the site is far from any ice sheet on modern Mars, its unusual landforms are associated with old volcanoes under ice. Now volcanic minerals have been found as well. Image via NASA/JPL-Caltech/JHUAPL/ASU

We know that Mars had extensive volcanism in the past; in fact, it has the largest extinct volcano known in our solar system. On May 3, 2016, NASA said that evidence is building for old volcanoes that erupted under Martian ice billions of years ago.

Four mini-Neptunes orbiting in lock step

For every three orbits of the outermost planet orbiting the star Kepler-223, the second planet orbits four times, the third six and the innermost eight.

Video: Ride along as a rocket lands

A rocketcam gives you a ringside seat on the April 2 upright landing of the Blue Origin’s New Shepard rocket.

Baby dino was self-reliant mini-me

Life-sized sculpture depicting how a baby Rapetosaurus might have looked in real life.  Aw! Image via Kristi Curry Rogers.

Life-sized sculpture depicting how a baby Rapetosaurus might have looked in real life. Image via Kristi Curry Rogers.

But, in the case of the fossil bones examined in this new study, the baby dinosaur lived only weeks, apparently dying of starvation.

Why Planet 9 shouldn’t exist

Artist's conception of Planet Nine, in the far outer solar system. In this image, the star in the lower right is our sun. Image via Caltech/R. Hurt (IPAC)

Artist’s conception of Planet Nine, in the far outer solar system. In this image, the star in the lower right is our sun. Image via Caltech/R. Hurt (IPAC)

Earlier this year, scientists presented evidence for a Planet Nine in the far outer solar system. Scientists think it exists, but – if so – how did it get there?