Last Year’s Total Solar Eclipse on Earth, Seen From the Moon

The Moon casting its shadow on the Earth during an eclipse in 2018. Image Credit: MingChuan Wei (Harbin Institute of Technology, BG2BHC/BY2HIT), CAMRAS Dwingeloo Radio Telescope, Reinhard Kühn DK5LA. Image edit by Jason Major.

On July 2, 2019, the Moon cast its shadow on the surface of the Earth. This time, the shadow’s path travelled across the South Pacific Ocean. It also passed over some of Argentina and Chile. For surface dwellers in the path, the Moon briefly blocked the Sun, turning night into day.

But for one “eye” in orbit around the Moon, the view was different. A camera on a tiny satellite watched as the circular shadow of the Moon moved over the Earth’s surface.

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Amazing View of How Dust Storms Grow on Mars

Two snapshots, about two weeks apart, of a 3D simulation of the 2018 Global Dust Storm performed with the NASA Ames Mars Global Climate Model. The storm began as a regional storm in Acidalia then moved eastward, triggering more dust lifting along the way (in Arabia, Sabaea, Hellas etc.). As the storm grew larger and became global, intense dust lifting events occurred in the Tharsis region, injecting dust at high altitudes. Credit: Tanguy Bertrand / Alex Kling / NASA Ames Research Center

In 2018, Mars experienced one of its global dust storms, a phenomenon seen nowhere else. As science would have it, there were no fewer than six spacecraft in orbit around Mars at the time, and two surface rovers. This was an unprecedented opportunity to watch and study the storm.

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New Hubble Photos of Planetary Nebulae

Hubble was recently retrained on NGC 6302, known as the "Butterfly Nebula," to observe it across a more complete spectrum of light, from near-ultraviolet to near-infrared, helping researchers better understand the mechanics at work in its technicolor "wings" of gas. Image Credit: NASA, ESA, and J. Kastner (RIT)

Planetary nebulae are astronomy’s gateway drug. Their eye-catching forms make us wonder what process created them, and what else is going on up there in the night sky. They’re some of the most beautiful, ephemeral looking objects in all of nature.

The Hubble Space Telescope is responsible for many of our most gorgeous images of planetary nebulae. But the images are more than just engrossing eye candy. They’re documentation of a complex process that plays out over tens of thousands of years, all across the Universe.

And they’re a death knell for the star that dwells within.

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Pluto and Other Kuiper Belt Objects Started Out With Water Oceans, and Have Been Slowly Freezing Solid for Billions of Years

Far left: Pluto and it's heart-shaped feature called “Tombaugh Regio” in honor of astronomer Clyde Tombaugh, who discovered the dwarf planet. The bright expanse of the western lobe of Pluto’s “heart” is informally called Sputnik Planum. Above left: Pluto’s surface sports a remarkable range of landforms that have their own distinct colors, telling a complex geological and climatological story. Credit: Courtesy NASA / JHUAPL / SwRI Table of Contents page 2015 Annual Report Division: (15)

It seems unlikely that an ocean could persist on a world that never gets closer than 30 astronomical units from the Sun. But that’s the case with Pluto. Evidence shows that it has a sub-surface ocean between 100 to 180 km thick, at the boundary between the core and the mantle. Other Kuiper Belt Objects may be similar.

But time might be running out for these buried oceans, which will one day turn to ice.

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Planets Form in Just a Few Hundred Thousand Years

Artist's conceptualization of the dusty TYC 8241 2652 system as it might have appeared several years ago when it was emitting large amounts of excess infrared radiation. Credit: Gemini Observatory/AURA artwork by Lynette Cook. https://www.gemini.edu/node/11836

Astronomers like to observe young planets forming in circumstellar debris disks, the rotating rings of material around young stars. But when they measure the amount of material in those disks, they don’t contain enough material to form large planets. That discrepancy has puzzled astronomers.

The answer might come down to timing.

A new study suggests that planets form much quicker than astronomers think.

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Quasars are the Biggest Particle Accelerators in the Universe

Composite image of Centaurus A, showing the jets emerging from the galaxy’s central black hole, together with the associated gamma radiation. © ESO/WFI (Optical); MPIfR/ESO/APEX/A.Weiss et al. (Submillimetre); NASA/CXC/CfA/R.Kraft et al. (X-ray), H.E.S.S. collaboration (Gamma)

We puny humans think we can accelerate particles? Look how proud we are of the Large Hadron Collider. But any particle accelerator we build will pale in comparison to Quasars, nature’s champion accelerators.

Those things are beasts.

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Astronomers Estimate There Are 6 Billion Earth-Like Planets in the Milky Way

Meet Kepler-22b, an exoplanet with an Earth-like radius in the habitable zone of its host star. Unfortunately its mass remains unknown. Image Credit: NASA

Six billion Earth-like planets in the Milky Way? If true, that’s astounding. But the number needs some context.

The Milky Way has up 400 billion stars. So even if there are six billion Earth-like planets, they’re still spread far and wide throughout our vast galaxy.

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NASA Thinks it’s Time to Return to Neptune With its Trident Mission

Artist's impression of what the surface of Triton may look like. Credit: ESO

Is it time to head back to Neptune and its moon Triton? It might be. After all, we have some unfinished business there.

It’s been 30 years since NASA’s Voyager 2 spacecraft flew past the gas giant and its largest moon, and that flyby posed more questions than it answered. Maybe we’ll get some answers in 2038, when the positions of Jupiter, Neptune, and Triton will be just right for a mission.

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Why Pulsars Are So Bright

Pulsars are fast-spinning neutron stars that emit narrow, sweeping beams of radio waves. A new study identifies the origin of those radio waves. NASA’s Goddard Space Flight Center
Pulsars are fast-spinning neutron stars that emit narrow, sweeping beams of radio waves. A new study identifies the origin of those radio waves. NASA’s Goddard Space Flight Center

When pulsars were first discovered in 1967, their rhythmic radio-wave pulsations were a mystery. Some thought their radio beams must be of extraterrestrial origin.

We’ve learned a lot since then. We know that pulsars are magnetized, rotating neutrons stars. We know that they rotate very rapidly, with their magnetic poles sending sweeping beams of radio waves out into space. And if they’re aimed the right way, we can “see” them as pulses of radio waves, even though the radio waves are steady. They’re kind of like lighthouses.

But the exact mechanism that creates all of that electromagnetic radiation has remained a mystery.

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Barred Spiral Galaxy NGC 2608, Surrounded by Many Many Other Galaxies

Looking deep into the Universe, the NASA/ESA Hubble Space Telescope catches a passing glimpse of the numerous arm-like structures that sweep around this barred spiral galaxy, known as NGC 2608. Appearing as a slightly stretched, smaller version of our Milky Way, the peppered blue and red spiral arms are anchored together by the prominent horizontal central bar of the galaxy. In Hubble photos, bright Milky Way stars will sometimes appear as pinpoints of light with prominent lens flares. A star with these features is seen in the lower right corner of the image, and another can be spotted just above the pale centre of the galaxy. The majority of the fainter points around NGC 2608, however, lack these features, and upon closer inspection they are revealed to be thousands of distant galaxies. NGC 2608 is just one among an uncountable number of kindred structures. Similar expanses of galaxies can be observed in other Hubble images such as the Hubble Deep Field which recorded over 3000 galaxies in one field of view.

Meet NGC 2608, a barred spiral galaxy about 93 million light years away, in the constellation Cancer. Also called Arp 12, it’s about 62,000 light years across, smaller than the Milky Way by a fair margin. The Hubble Space Telescope captured this image with its Wide-Field Camera 3 (WFC3).

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