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Only two countries use purple in their national flags.
The flag of Nicaragua features a rainbow in the center that includes a band of purple, while the flag of Dominica boasts a picture of a sisserou parrot, a bird with purple feathers. These elements make them the only two flags in the world that use the color purple.

Gjermund Roesholt left the cabin on Einarson Lake, in the remote backcountry of the central Yukon, around 9:30 A.M. on November 26, 2018. He headed out by snowmobile to check a trapline that was laid north of the cabin. His partner, Valérie Théorêt, stayed behind with their ten-month-old baby girl, Adèle.

Théorêt was a grade-school teacher on maternity leave; Roesholt was a wilderness and hunting guide. The couple, who normally lived in Whitehorse, the Yukon’s small capital city, had flown in to their cabin on October 4, intending to stay until the new year, when Théorêt was due back at school. At the cabin, they hunted for game and maintained their modest trapping concession, a designated area where they were permitted to catch and kill small fur-bearing mammals, living out a dream of rugged self-sufficiency. Both were experienced in the wild, and they were careful about attractants—they stored the remnants of their hunts in a secure container inside a shed a short distance from the cabin.

Around 2:30 in the afternoon, five hours after he’d set out, Roesholt was working his way back toward home. It had snowed gently on and off throughout his morning on the trapline, and as he retraced his own newly dusted trail, he could see fresh bear tracks heading in the same direction. Before he reached the cabin, the tracks turned away.

When he got to the cabin, it was quiet. Théorêt and Adèle were not inside. Roesholt walked down the well-used trail toward a sauna, calling their names. Increasingly worried, he knew he might have to use the loaded rifle he carried.

His partner and child were not at the sauna. Roesholt kept going, down a trail they used for a small trapline that was close enough to the cabin to be checked on foot. He was about 800 feet from the structure when he heard a bear growl.

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You might think that letting gravity pull you closer to a massive object is easier than trying to pull yourself away from that massive object. Certainly if all you want to do is fall that might be true. But if you start out in a stable orbit, and you want to reach another stable orbit, and you want to get into orbit around another massive object already orbiting the first massive object, well, you have some work to do.

Take for instance the challenge of visiting the planet Mercury, orbiting the Sun at an average distance of 36 million miles compared to Earth's average 93 million miles. At this position Mercury's orbital velocity is some 1.6 times that of the Earth (which is already a hefty 30 kilometers-per-second), requiring some substantial work to match. As always in spaceflight the critical currency is 'delta-v', the net change in velocity required to get from A to B. For trips from Earth to Mercury that delta-v is costly, so we have to be clever and sneak up on it.

For the European Space Agency's BepiColombo mission to Mercury the trick is a seven-year transfer utilizing no less than 9 planetary flybys to exploit a teeny tiny bit of planetary orbital angular momentum (and gravity) to maneuver into a gentle intersect with the Sun's inner world. BepiColombo is actually two spacecraft in one: an orbiter with telescopic imaging, spectrometers (including gamma-ray and neutron - good for seeking signs of frozen water), and a suite of other instruments, and a separate orbiter for studying Mercury's magnetospheric environment.
Launched in October of 2018 into a heliocentric (Sun-centric) orbit similar to Earth's it will use a sequence of planetary encounters to finally arrive at a 'weak capture' into a polar orbit around Mercury in December 2025. The first major encounter just took place this week on April 10th 2020, as BepiColombo scooted by Earth at a nerve-wrackingly close distance of about 12,700 kilometers. In doing so it provided a beautiful view (shown here at roughly 220,000 kilometer distance) of our crescent world - a much needed reminder that there are things beyond our daily human trials, and that our world perseveres.

The European and Japanese BepiColombo mission has made its first fly-by of Mercury, passing just 199 kilometres above the planet’s surface at 23:34 UTC on 1 October.

It captured black-and-white pictures of Mercury’s crater-filled surface from a distance of about 1,000 kilometres; BepiColombo flew around Mercury’s nightside, so it was not able to take photographs at its closest approach. The shots were taken by auxiliary cameras at relatively low resolution, because the mission’s main cameras are tucked away during interplanetary travel.

The 4.1-tonne, €1.6-billion (US$1.85-billion) spacecraft launched in October 2018 and will enter permanent orbit around Mercury in 2025. It carries two probes, one built by the European Space Agency (ESA) and the other by the Japan Aerospace Exploration Agency (JAXA). The ESA probe will map Mercury’s surface and gravitational field to study its inner structure. The JAXA probe will look at Mercury’s magnetic field and its interaction with the solar wind. BepiColombo has already performed one fly-by at Earth and two at Venus, and this is the first of six it will make at Mercury. “The Mercury fly-by is special because Mercury is our target planet for our science investigations,” says project scientist Johannes Benkhoff, a planetary physicist at ESA in Noordwijk, the Netherlands.

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Fly-bys are ‘gravity assist’ manoeuvres, which enable interplanetary ships to either gain or lose momentum and modify their orbits around the Sun without consuming large amounts of fuel. BepiColombo uses them to brake, so that it falls towards the inner Solar System. This way, the spacecraft will ultimately synchronize its trajectory with that of the innermost planet, Mercury, so it can enter orbit. Some of the two probes’ instruments, in particular the on-board magnetometers, collect data during the fly-bys, says Benkhoff. This could enable the team to start getting its first science results.

Once in orbit, a major focus for the craft will be water-ice deposits inside permanently shaded craters in Mercury’s polar regions. The ice—which is surprising on a planet where daytime surface temperatures exceed 400 °C—was discovered by NASA’s MESSENGER mission, which studied Mercury between 2011 and 2015 and is so far the only mission to have orbited the planet.

“I'm just so excited to see Mercury close up again, even if just briefly for this fly-by,” says Nancy Chabot, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland. Chabot was the leading scientist for MESSENGER. “I've really missed seeing the planet,” she says.

welcome here, bro!