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NGC 2992 (center) and its partner NGC 2993 (above left of center) // Steve Perry

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Red Sprites over Oklahoma l Domenico

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Rotating Moon from LRO

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Heads of Ramesses II taken from the facade of the Great Temple at Abu Simbel during its relocation, 1966

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Mysterious spiral near LL Pegasi ©

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The Crab Nebula (Webb/Chandra composite) by NASA's James Webb Space Telescope

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WR 134, Cygnus

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Two Hemisphere Night Sky

Credits: PetrHorálek, Juan Carlos Casado, TWAN

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Twin Tails of Comet Pons-Brooks

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The Crab Nebula (Webb/Chandra composite) by NASA's James Webb Space Telescope

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(🛸)

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Cometary Knots in the Helix Nebula - April 16th, 1996.

"Four hundred fifty light-years from Earth, the wind from a dying, Sun-like star produced a planetary nebula, popularly known as the Helix. While exploring the Helix's gaseous envelope with the Hubble Space Telescope (HST), astronomers discovered indications of 1,000s of striking "cometary knots" like those shown above. So called because of their resemblence to comets, they are actually much larger - their heads are several billion miles across (roughly twice the size of the our Solar System itself) while their tails, pointing radially away from the central star, stretch over 100 billion miles. Previously known from ground-based observations, the sheer number of cometary knots found in this single nebula is astonishing. What caused them to form? Hot, fast moving shells of nebular gas overrunning cooler, denser, slower shells ejected by the star during an earlier expansion may produce these droplet-like condensations, as the two shells intermix and fragment. An intriguing possibility is that instead of dissipating over time, these objects could collapse and form Pluto-like bodies. If so, these icy worlds created near the end of a star's life would be numerous in our galaxy."

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WHY IS VOYAGER 1 SENDING GIBBERISH??

Blog#391

Wednesday, April 10th, 2024.

Welcome back,

For months now, the most distant spacecraft to Earth – Voyager 1 – has been talking gibberish on the interplanetary 'radio'.

The repetitive jumble of 1s and 0s it's sending back to our planet, 24 billion kilometers (15 billion miles) away, has made no sense to scientists until now.

Turns out, officials at NASA just needed to give the oh-so-distant craft a bit of a 'poke' to ask it how it was feeling.

In response to a coded command sent in March, a computer onboard the Voyager called the flight data subsystem (FDS) has revealed where it hurts. This system wraps up the mission's all-important observations before beaming them back to Earth.

The system returned a software readout to Earth that scientists have now used to confirm about 3 percent of its memory is corrupted. Which is why turning the FDS on and off didn't resolve the issue back in November of 2023.

Based on the gobbledygook data the FDS is currently packaging, engineers at NASA suspect that most of the corruption is confined to a single chip in the computer's memory system.

In March, the Voyager mission team at NASA sent a so-called poke command to the FDS. Poke commands modify specific memory addresses, which is why gamers sometimes use them to cheat, by giving themselves unlimited lives or some such similar advantage.

In this case, the command allowed the engineers to prompt the system into using different readout sequences in its software packages in an effort to circumvent the problem.

Thanks to the FDS' response to the poke command, received 22.5 hours later, engineers noticed that one part of the system was returning some strange readings. They appeared to be in the wrong format, and an engineer on the team was able to decode them.

The mumbo jumbo signal contained a readout of the entire FDS memory system. Comparing this readout to one received before the issue arose, the Voyager team was able to locate the source of corruption.

No one yet knows what originally caused the corruption, but it could have come from energetic particles in space sparking damage, or simply sheer age.

Voyager 1 has gone above and beyond its initial mission, both figuratively and literally speaking. It was designed to explore Jupiter and Saturn and was launched all the way back in 1977, which means its computers are wildly outdated.

Originally published on www.sciencealert.com/

COMING UP!!

(Saturday, April 13th, 2024)

"HOW DID THE MOON FORM??"

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annular eclipse October 14

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Solar eclipse from Mars

We're uniquely situated with our Moon to produce total eclipses of the Sun - the geometry is such that, from our POV, our sister world completely covers our star when its orbit is just right.

Though Mars has two moons, they're both absolutely tiny compared to our Moon - Phobos is 17 miles (27 km) in diameter along its largest axis, and Deimos is only 7.6 miles (12.4 km) across. BTW, Mars is only about half the size of Earth (4219 miles/ 6790 km vs our 7922 miles/ 12750 km), but even proportionally they're teeny.

And even though they orbit way closer to Mars than our Moon orbits us, Mars orbits much farther away from the Sun (average 1.52 times as distant) - thus the disc of the Sun in the Martian sky is just a little over half its size in our sky.

So even with all the geometric advantages, those moons are so minute they just can't blot out much of the Sun during an eclipse.

Here's a Martian-POV solar eclipse courtesy of Phobos:

Perseverance rover took this video a couple years ago - it's the most zoomed-in, highest frame-rate observation of a Phobos solar eclipse ever taken from the Martian surface. (That's about the sunspot population we saw during our most-recent eclipse, too!)

Mars may never get a solar eclipse like those we enjoy on Earth, but they're still pretty cool.

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Total Solar Eclipse l Bray Falls l April 2024