Wednesday, January 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.

Back country 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).

"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.


.. 9.30pm .. 


COMET 46P/WIRTANEN NEAR MUSCIDA Taken by Yasushi Aoshima on January 9, 2019 @ Ishikawa, JAPAN

Muscida (οUMa).
Data: EF300mmF2.8L USM, CanonEOS6D, 12800 ISO, 118x60sec stacked (12:54-14:54 UT), North: lower, FOV: 4.7 x 7°

IC 342: THE HIDDEN GALAXY Image Credit & Copyright: Arturas Medvedevas

Similar in size to large, bright spiral galaxies in our neighborhood, IC 342 is a mere 10 million light-years distant in the long-necked, northern constellation Camelopardalis. A sprawling island universe, IC 342 would otherwise be a prominent galaxy in our night sky, but it is hidden from clear view and only glimpsed through the veil of stars, gas and dust clouds along the plane of our own Milky Way galaxy. Even though IC 342's light is dimmed and reddened by intervening cosmic clouds, this sharp telescopic image traces the galaxy's own obscuring dust, young star clusters, and glowing pink star forming regions along spiral arms that wind far from the galaxy's core. IC 342 may have undergone a recent burst of star formation activity and is close enough to have gravitationally influenced the evolution of the local group of galaxies and the Milky Way.

Monday, January 14, 2019


VELA SUPERNOVA REMNANT MOSAIC Image Credit & Copyright: Robert Gendler, Roberto Colombari, Digitized Sky Survey (POSS II)

The plane of our Milky Way Galaxy runs through this complex and beautiful skyscape. Seen toward colorful stars near the northwestern edge of the constellation Vela (the Sails), the 16 degree wide, 200 frame mosaic is centered on the glowing filaments of the Vela Supernova Remnant, the expanding debris cloud from the death explosion of a massive star. Light from the supernova explosion that created the Vela remnant reached Earth about 11,000 years ago. In addition to the shocked filaments of glowing gas, the cosmic catastrophe also left behind an incredibly dense, rotating stellar core, the Vela Pulsar. Some 800 light-years distant, the Vela remnant is likely embedded in a larger and older supernova remnant, the Gum Nebula. Objects identified in this broad mosaic include emission and reflection nebulae, star clusters, and the remarkable Pencil Nebula.

PARTIAL ECLIPSE OVER BEIJING Image Credit & Copyright: Li Zhaoqi

Explanation: On January 6 the New Moon rose in silhouette with the Sun seen from northeastern Asia. Near maximum, the dramatic partial solar eclipse is captured in this telephoto view through hazy skies. In the foreground, the hill top Wanchun pavilion overlooking central Beijing's popular Forbidden City hosts eclipse-watching early morning risers. This was the first of five, three solar and two lunar, eclipses for 2019. Next up is a total lunar eclipse during this month's Full Perigee Moon. At night on January 21, that celestial shadow play will be visible from the hemisphere of planet Earth that includes the Americas, Europe, and western Africa.

MILKY WAY FALLS Image Credit & Copyright: Yuri Beletsky (Carnegie Las Campanas Observatory, TWAN)

It can be the driest place on planet Earth, but water still flows in Chile's Atacama desert, high in the mountains. After discovering this small creek with running water, the photographer returned to the site to watch the Milky Way rise in the dark southern skies, calculating the moment when Milky Way and precious flowing water would meet. In the panoramic night skyscape, stars and nebulae immersed in the glow along the Milky Way itself also shared that moment with the Milky Way's satellite galaxies the Large and Small Magellanic clouds above the horizon at the right. Bright star Beta Centauri is poised at the very top of the waterfall. Above it lies the dark expanse of the Coalsack nebula and the stars of the Southern Cross.

LIGHT PILLARS Taken by Stephanie Graudons on January 12, 2019 @ Lebanon, New Hampshire, USA

Below zero temperatures and partially open rivers formed light pillars over Lebanon, New Hampshire just before sunrise.

Sunday, January 6, 2019

COMET IWAMOTO (C/2018 Y1) Taken by Yasushi Aoshima on January 3, 2019 @ Shizuoka, JAPAN

Data: EF300mmF2.8L USM, CanonEOS6D, 12800 ISO, 67x60sec stacked (19:35-20:43 UT), North: upper, FOV: 7 x 4.7°

COMET 38P/STEPHAN-OTERMA Taken by Yasushi Aoshima on December 15, 2018 @ Shizuoka, JAPAN

Data: EF300mmF2.8L USM, CanonEOS6D, 12800 ISO, 32x60sec stacked (19:32-20:35 UT), North: upper, FOV: 4.7 x 7°

COMET 64P/SWIFT-GEHRELS IN TRI Taken by Yasushi Aoshima on December 10, 2018 @ Ishikawa, JAPAN

Data: EF300mmF2.8L USM, CanonEOS6D, 12800 ISO, 21x60sec stacked (11:09-33 UT), North: upper-right, FOV: 4.7 x 7°

COMET 46P/WIRTANEN NEAR M45 Taken by Yasushi Aoshima on December 15, 2018 @ Shizuoka, JAPAN

Data: EF300mmF2.8L USM, CanonEOS6D, 12800 ISO, 118x60sec stacked (14:04-17:10 UT), North: right-upper, FOV: 7 x 4.7°



ECLIPSED SUN Taken by Shiraishi on January 6, 2019 @ Kumagaya-shi, Saitama, Japan

Partial solar eclipse from Japan at 10 oclock UTC+9 Jan. 6 (approx. maximum eclipse)

Nikon COOLPIX B700 digital camera; ISO 100, F6.5, 1/640s exposure, f=1440mm

Friday, January 4, 2019


James Kevin Ty took this picture from the Philipines during a eclipse in Jan. 2010. "The low-hanging sun was dim and I didn't need any special filter to photograph it using my Canon 350D," says Ty. "In the foreground, a young couple sat together in a boat enjoying the romantic view."