Meteors, meteoroids and meteorites normally originate from asteroids and comets.
For example, if Earth passes through the tail of a comet, much of the debris burns up in the atmosphere, forming a meteor shower.
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This map of Jupiter is the most detailed global color map of the planet ever produced. The round map is a polar stereographic projection that shows the south pole in the center of the map and the equator at the edge. It was constructed from images taken by Cassini on Dec. 11 and 12, 2000, as the spacecraft neared Jupiter during a flyby on its way to Saturn. The map shows a variety of colorful cloud features, including parallel reddish-brown and white bands, the Great Red Spot, multi-lobed chaotic regions, white ovals and many small vortices. Many clouds appear in streaks and waves due to continual stretching and folding by Jupiter’s winds and turbulence. The bluish-gray features along the north edge of the central bright band are equatorial “hot spots,” meteorological systems such as the one entered by NASA’s Galileo probe. Small bright spots within the orange band north of the equator are lightning-bearing thunderstorms. The polar region shown here is less clearly visible because Cassini viewed it at an angle and through thicker atmospheric haze. Image Credit: NASA/JPL/Space Science Institute
This is probably a bit more repetition, but well worth the time! So digital modes are where data are encoded as bits instead of in waves, and some are created commercially, while others are created by amateurs!
Digital modes consist of two things: a protocol and a method of modulation. A protocol is the set of rules that control the encoding, packaging, exchanging and decoding of digital data. For example, packet radio uses the AX.25 protocol standard. This standard says how each packet is constructed, how packets are exchanged, what characters are allowed, and so forth. The protocol standard doesn’t say what kind of transmitter to use or what the signal will sound like on the air.
Digital mode signals are restricted to the CW/data segments of each band and most digital mode operation is close to the top of the CW segment. Calling frequencies for the popular digital modes are incorporated into band plans and are usually the lowest frequency of operation with operators moving up in frequency as activity increases.
For example on 20m, most PSK31 signals are found near 14.070 MHz. RTTY and other digital mode signals are found above that. The modems used for digital signals often do not recognize signals from CW or other digital modes.
Here’s the Digital Signal Band Plan:
@atdiy/@tymkrs
Cometary Globules
Comet 67P/C-G is framed by one of Rosetta’s solar wings, which is 46 feet long. A stream of gas and dust extends from an active area of the comet’s neck, about 10 miles away. (via NY Times)
Knate Myers - View from the ISS at Night
1. Powered by the Sun
Fifty-nine years ago, Vanguard 1 launched to demonstrate a new spacecraft technology – solar power. We’ve been going farther and for longer ever since.
+More on Vanguard 1
2. Mapping Mercury
A big week in history for exploration of the innermost planet. On March 16, 1975, our Mariner 10 made its third and final flyby of Mercury. One day and 36 years later, MESSENGER became the first spacecraft to orbit Mercury. Next up: ESA’s BepiColumbo, undergoing testing now, is set to launch for Mercury in 2018.
+Missions to Mercury
3. Return to Venus
U.S. and Russian scientists are discussing a planned revival of the successful Venera program that revealed much about Venus in the 1960s, 70s and 80s. Meanwhile, Japan’s Akatsuki orbiter continues to study our sister planet.
+More on Venera-D
4. Rocket Power
Back on Earth 91 years ago (March 16, 1926), inventor and dreamer Robet Goddard changed the world forever with the first test of a liquid-fueled rocket. We’ve been going farther and faster ever since.
+More on Goddard
5. Moon Watch
Our Lunar Reconnaissance Orbiter (LRO) has been sending a steady stream of high-resolution images back to Earth for more than seven years.
+More on LRO
6. Busy Mars
There are currently five orbiters (Mars Reconnaissance Orbiter, Mars Odyssey, MAVEN, ESA’s Mars Express and India’s Mars Orbiter Mission) and two rovers (Curiosity and Opportunity) exploring Mars, making it second only to Earth in the number of robotic spacecraft studying its secrets.
+Meet the Mars Fleet
7. Vote for Jupiter
Polls close today (March 20) so vote not to point a real spacecraft camera at Jupiter during the mission’s 5th perijove pass.
+Vote now
8. Science to the Last Second
In a little less than six months, our Cassini orbiter will plunge into Saturn as a spectacular finale to its 19-year mission – but not before it embarks on a completely new mission into unexplored space between Saturn and its mighty rings.
+More on Cassini’s Grand Finale
9. By George?
Happy belated birthday to Uranus, discovered on March 13, 1781 by William Herschel. The English astronomer wanted to name his discovery – the first planet discovered in recorded history – “Georgium Sidus” after England’s King George III. But he was overruled, and astronomer stuck with traditional mythological names – creating an opportunity for 263 years of student jokes at the expense of the ice giant planet’s name.
+More on Uranus
10. Go Farther
The round trip light time from Voyager 1 to Earth is more than 38 hours. Voyager 1 is almost 13 billion miles from our home planet.
+More on Voyager
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Ted Chin