Jan. 22, 2019: On Jan. 21st at 04:41:43 UT, a meteoroid slammed into the Moon. We know this because so many people witnessed the explosion. It happened during a total eclipse of the Moon, visible from five continents. Dr. Fritz Helmut Hemmerich photographed the eclipse from the Canary Islands of Spain and captured the fireball:

“This is a happy shot!” says Hemmerich. “The shot just before and the shot just a few seconds later show nothing. The fireball was short-lived and I’m glad I caught it in this 2-second exposure.”

Dozens of reliable images and videos of the impact have surfaced in the days since the eclipse. Analyzing one sharp image taken by Christian Fröschlin of the Netherlands, geologist Justin Cowart has estimated the selenographic coordinates of the impact site: 29.47S, 67.77W +/- 4km. This puts it just to the west of the lunar crater Lagrange H. NASA’s Lunar Reconnaissance Orbiter may be able to use such coordinates to target its cameras and photograph the crater.

Meteoroids hit the Moon all the time. Literally. NASA has been observing impact flashes since 2005. Recently, other groups in Europe have joined the hunt. Flashes are typically recorded once every 2 to 3 hours of observing time. Impactors range in size from softballs to boulders, liberating energies equal to tons of TNT when they strike.

Above: The impact flash, photographed by Hunter McWilliams of Lubbock, Texas

The rare thing about this strike is that it was photographed during a full Moon, when lunar glare usually overwhelms the glow of any fireball. During the eclipse, Earth’s shadow turned lunar day into almost-night for an hour, allowing the fireball to be seen.

Readers, were you taking pictures of the eclipse around 04:41 UT? Check your photos. You might have captured an explosion. Submit images here.

Realtime Eclipse Photo Gallery

Jan. 16, 2019: Pick up your cell phone and look at it. That rectangular marvel of modern technology contains thousands of lines of code. Among them is the World Magnetic Model (WMM)–a program that helps your phone navigate.  And it’s in a bit of trouble. Researchers have announced that the WMM needs an emergency update because Earth’s magnetic field is changing.

Savvy backcountry hikers have long known that compass needles don’t really point north. The magnetic north pole is displaced hundreds of miles from the true north pole and, to make matters worse, it wanders unpredictably from year to year. To find true north in the continental USA, you have to correct compass directions by as much as 20 degrees using a special “declination table.”

The World Magnetic Model is a computer program that makes this correction for you. It improves the navigation of devices ranging from nuclear submarines to common smartphones.

“The WMM is the standard magnetic model used for navigation by organizations such as NATO, the Ministry of Defence, and the US Department of Defense, and also by smartphone operating systems such as Android and iOS,” explains Will Brown of the British Geological Survey’s Geomagnetism Team, which produces the model in collaboration with NOAA of the USA.

“When you open your smartphone’s map app, you may see an arrow pointing which way you’re facing, and there’s something quite clever going on underneath,” he continues. “Your phone contains a magnetometer that is measuring the Earth’s magnetic field. In order to make sense of this information, Android and iOS operating systems use the WMM to correct the measurements to true north.”

Normally the World Magnetic Model is updated every 5 years. For decades that’s been often enough to track natural changes in our planet’s magnetism caused by fluctuations in Earth’s molten core. But suddenly things are changing faster than before.

Annual rate of change of declination for 2015.0 to 2020.0 from the World Magnetic Model (WMM2015). This information is about to be updated by a new WMM.

“Since late 2014, Earth’s core field has varied in an unpredicted, and currently unpredictable, manner [including a sudden change in declinaton called a ‘geomagnetic jerk‘ in 2014/2015],” says Brown. “The aim of the WMM is to be globally accurate within 1 degree of declination, but we were going to exceed that limit in only 3 years.” That’s why, for the first time, they are issuing an update to the WMM before the usual 5 year mark in 2020.

The new model is based data from a global network of 160 surface observatories and satellites in low-Earth orbit such as ESA’s Swarm mission. It was supposed to be released on Jan. 15th but has been delayed until Jan. 30th because of the partial shutdown of the US government.

Jan. 14, 2019: Last week, astronomers working with the ATLAS project in Hawaii announced an astonishing change to asteroid 6478 Gault. The space rock had sprouted a tail. It is now gliding through the asteroid belt giving every appearance of being a comet. On Jan. 9th, Damian Peach of Selsey UK photographed the 6478 Gault and its 400,000 kilometer-long tail:

“This is a 60 minute sequence of images, which I captured using a 20-inch telescope,” says Peach.

What happened to 6478 Gault? A clue may be found in its lineage. Asteroid Gault is a member of the Phocaea family, a swarm of rocks in the inner asteroid belt that formed as a result of inter-asteroid collisions some 2.2 billion years ago. The family gets its name from its most massive survivor, 25 Phocaea, which is about 75 km in diameter.

Gault’s tail may be a result of a recent collision. Researchers with the ATLAS project have looked at images of Gault in Dec. 2018 and Jan. 2019. Extrapolating its appearance backwards in time, they suggest that Gault hit another object in the asteroid belt in Nov. 2018. If that idea is correct, the tail would be debris from the crash.

Asteroid Gault was discovered in 1988 by the famous astronomer couple Carolyn and Eugene Shoemaker at the Palomar Observatory in California. For the next 30 years, the 4-km wide space rock did little to attract attention. Now, astronomers around the world are eagerly monitoring 6478 Gault to see what happens next. Stay tuned.

Readers, would you like to take pictures like Damian Peach? He’s willing to teach you how. Subscribe to his Patreon page for expert tutorials.

Realtime Space Weather Photo Gallery

FULL MOON VALENTINE’S PENDANT: Poets, lovers, and artists have long known this simple truth: Nothing is more romantic than a full Moon. Now you can give the full Moon as a Valentine’s Gift–the full Moon space pendant, that is. This one flew to the stratosphere on Dec. 26, 2018, onboard an Earth to Sky Calculus cosmic ray balloon:

You can have it for $99.95. The students are selling these spherical glass pendants to support their cosmic ray ballooning program. Each one comes with a Valentine’s card showing the pendant in flight and telling the story of its journey to the edge of space and back again.

Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education

Jan. 3, 2019: Going where no nation has gone before, today China successfully landed a rover on the farside of the Moon. The Chang’e 4 lunar probe touched down in the South Pole-Aitken Basin, the largest, deepest and oldest known crater in the solar system, at 10:26 am Beijing time on Jan. 3rd.

From Earth, we can see only one side of the Moon. The other side, the farside, is perpetually hidden from view. Apollo astronauts have flown over the farside of the Moon, and many satellites have photographed the Moon from behind–revealing it to be a rugged, heavily cratered landscape startlingly different from the side we typically see.

China’s rover will be the first to explore a farside crater, probing it with ground-penetrating radar and measuring its mineral composition with an infrared spectrometer. If water is present, the rover might find it.

The first pictures of the landing site have been relayed to Earth by the Queqiao satellite, which China launched in May 21, 2018, specifically for this purpose. This is what the South Pole-Aitken Basin looks like from the inside:

The landing was remarkable. Mission control had no line-of-sight contact with the lunar farside, so the lander had to perform many complex maneuvers autonomously. (1) As it descended to an altitude of about 2 km, onboard cameras captured the shadows of objects on the lunar surface, identifying large obstacles such as rocks and craters so the probe could avoid them. (2) At 100 meters up, the probe hovered to identify smaller obstacles and measured the slopes on the surface. Its computer calculated again and selected the safest site. (3) At 2 meters above the surface, the engine stopped. Then the golden lander with a silver rover on top touched down on the desolate gray surface with four legs, throwing up some dust. The probe performed the entire landing process, lasting about 12 minutes with no intervention from ground control.

Realtime Space Weather Photo Gallery

GIFTS FROM THE EDGE OF SPACE: The students of Earth to Sky Calculus are about to kick off a new year of cosmic ray balloon launches, continuing a 5-year campaign to monitor increasing levels of radiation in Earth’s atmosphere. You can help. Buy any gift item from the Earth to Sky Store and we’ll give you 10% off to celebrate the New Year.

All items in the Earth to Sky Store have flown to the edge of space onboard cosmic ray balloons. Each one comes with a greeting card showing the item in flight and telling the story of its journey. All sales support the Earth to Sky Calculus cosmic ray ballooning program and hands-on STEM research.

Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education

Jan. 2, 2019: The first high-resolution images of Ultima Thule have reached Earth following New Horizons’ historic flyby on New Year’s Day. Hot off the presses, the photos reveal a pair of roughly spherical planetestimals stuck together in the middle. The contact binary strangely resembles BB-8:

“This flyby is a historic achievement,” says New Horizons Principal Investigator Alan Stern of the Southwest Research Institute in Boulder, Colorado. “Never before has any spacecraft team tracked down such a small body so far away in the abyss of space. We’re getting our first close-up look at ancient planetesimals.”

Planetestimals are the building blocks of planets. Here in the inner solar system, no pristine examples remain for us to study. They have been swallowed by planets, hammered by asteroids, and scorched by solar radiation. Ultima Thule, however, has been preserved in the deep freeze of the outer solar system for more than 4 billion years. It is truly a relic of the genesis of planets.

Mission scientists believe that Ultima Thule formed by accretion. A swarm of smaller planetesimals gathered under the pull of their own meagre gravity to form two spherical bodies, medium-sized planetesimals which themselves slowly bumped together and stuck. The result was Ultima Thule.

This is just the beginning of Ultima Thule’s revelations. First images released today have a resolution of about 140 meters per pixel. Images arriving in the days and weeks ahead will be as much as 5 times sharper, possibly revealing craters, hills, landslides, rilles and other unknowns.

New Horizons also scanned the area for tiny moons–the debris of the original swarm that gave birth to this strange object. Detections, if any, will be revealed in future transmissions from the spacecraft.

Browse: Slides from the science briefing and latest images from New Horizons