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Rocky debris caused by a NASA mission could create the first human-made meteor shower.
In Sept. 2022, NASA’s Double Asteroids Redirect Test (DART) intentionally collided with a tiny moonlet named Dimorphos, which orbited the asteroid Didymos, to test its asteroid deflection technology.
Scientists believe the crash produced over 2 million pounds of rocks and dust — and a new study suggests fragments of Dimorphos could land around Earth and Mars in 10 to 30 years, and the meteor showers could last for up to a century.
A sharp decline in sunspot activity in the 17th century has long puzzled astronomers. //
We realized that this [Kepler's] sunspot drawing should be able to tell us the location of the sunspot and indicate the solar cycle phase in 1607 as long as we managed to narrow down the observation point and time and reconstruct the tilt of the heliographic coordinates—meaning the positions of features on the Sun's surface—at that point in time.” //
German astronomer Gustav Spörer noted the steep decline in 1887 and 1889 papers, and his British colleagues, Edward and Annie Maunder, expanded on that work to study how the latitudes of sunspots changed over time. That period became known as the "Maunder Minimum." Spörer also came up with "Spörer's law," which holds that spots at the start of a cycle appear at higher latitudes in the Sun's northern hemisphere, moving to successively lower latitudes in the southern hemisphere as the cycle runs its course until a new cycle of sunspots begins in the higher latitudes.
But precisely how the solar cycle transitioned to the Maunder Minimum has been far from clear. //
"It is fascinating to see historical figures’ legacy records convey crucial scientific implications to modern scientists even centuries later," said co-author Sabrina Bechet of the Royal Observatory of Belgium. "I doubt if they could have imagined their records would benefit the scientific community much later, well after their deaths. We still have a lot to learn from these historical figures, apart from the history of science itself. In the case of Kepler, we are standing on the shoulders of a scientific giant."
Perseid meteors will streak through Earth’s atmosphere starting in mid-July. A first quarter moon won’t interfere with the shower’s peak on the mornings of August 11, 12 and 13.
It is about 3,000 light-years from Earth, but it can be witnessed with the naked eye. //
NASA predicts a nova will occur sometime this summer, about 3,000 light-years from Earth, but it can be witnessed with the naked eye.
The nova reoccurs once every 80 years. //
The nova should happen in a dark spot among the seven stars of Corona Borealis, known as the Northern Crown.
The dark spot contains “two stars that are bound to and in orbit around each other,” known as T Coronae Borealis or T CrB. NASA nicknamed it the Blaze Star:
Scientists carried out a survey of five million distant solar systems with the help of 'neural network' algorithms and it took an interesting turn when they found nearly 60 stars surrounded by what appeared as "giant alien power plants."
Among the 60 stars, seven of them - which were M-dwarf stars and ranged between 60 per cent and 8 per cent the size of the Sun - were seen releasing high infrared 'heat signatures,' as per the astronomers. //
While these structures are named for Freeman Dyson, a physicist and mathematician who proposed the building of a Dyson sphere to contain and capture all of a star's energy output, the concept actually goes back to a 1937 novel, Star Maker, by author Olaf Stapledon.
But as far as this study actually having detected such structures? Color me skeptical. //
What isn't said is what other explanations might cause these mid-infrared emissions; while I'm a biologist and not a cosmologist, it seems to me that a G-sequence star like our sun, were it to be surrounded by a cloud (or clouds) of gas or dust, may well also emit such an IR signature. And that's a lot more likely than an alien civilization that would by necessity be thousands, or millions of years ahead of us, technologically. //
Cliff-Hanger
3 hours ago
Ward, I'm a little disappointed. Dyson structures mentioned and not one bad pun about vacuum cleaners sucking the energy out of the stars.
Slowing down an asteroid by just one-tenth of a second makes all the difference.
This graph shows the number of sunspots seen each year for 400 years (from 1600 to 2000). There were almost no sunspots during the Maunder Minimum. During the Dalton Minimum, there were fewer sunspots than normal. //
The first written record of sunspots was made by Chinese astronomers around 800 B.C. Court astrologers in ancient China and Korea, who believed sunspots foretold important events, kept records off and on of sunspots for hundred of years. An English monk named John of Worcester made the first drawing of sunspots in December 1128. //
It would appear that sunspots not only have a connection to geomagnetic activity at Earth, but they play a role in climate change as well. In the last thousands of years, there have been many periods where there were not many sunspots found on the Sun. The most famous is a period from about 1645 to 1715, called the Maunder Minimum. This period corresponds to the middle of a series of exceptionally cold winters throughout Europe known as the Little Ice Age. Scientists still debate whether decreased solar activity helped cause the Little Ice Age, or if the cold snap happen to occur around the same time as the Maunder Minimum. In contrast, a period called the Medieval Maximum, which lasted from 1100 to 1250, apparently had higher levels of sunspots and associated solar activity. This time coincides (at least partially) with a period of warmer climates on Earth called the Medieval Warm Period. Sunspot counts have been higher than usual since around 1900, which has led some scientists to call the time we are in now the Modern Maximum.
Good morning. It's May 1, and today's photo is ridiculously awesome. Taken by the James Webb Space Telescope, it features the sharpest infrared image of the Horsehead Nebula captured to date—it is so zoomed in we can only see the mane. Even so, the image covers an area that is nearly one light-year across, or about 7.6 trillion km.
The Horsehead Nebula is fairly close to Earth, as these things go, about 1,300 light-years. So, it is within our galaxy. In addition to the prominent star at the top of the image and a handful of other stars with six diffraction spikes, the rest of the objects in this image are distant galaxies.
In astronomy, a planetary transit is when a planet closer to the Sun passes in front of the Sun's disc as seen from a more distant planet. From the Earth, transits of Mercury and Venus are visible; recently, observers were treated to these spectacles in back-to-back years: 2003 and 2004.
In the run-up to the 2004 transit of Venus, I became obsessed with one of those silly questions which, once they sink their claws into one's mind, won't go away without being answered yes or no. Is there ever a simultaneous transit of Mercury and Venus visible from the Earth?
The naïve answer is, “Of course not (you idiot)! Transits can occur only when inferior conjunction with the inner planet coincides with its crossing the ecliptic. Transits of Venus always occur in June and December, transits of Mercury in May and November, and thus a simultaneous transit can never happen.”
But this doesn't take into account the evolution of planetary orbits over time. Analytical planetary theories such as VSOP87 are useless beyond the period for which they are fit (say, −4000 to +8000 years Gregorian). To go beyond that, you need to do full-up numerical integration of the motion of the Sun and planets.
Well, that's what computers are for, isn't it? So, I found a high-precision numerical integration code for the Solar System written by Steve Moshier, built a back-end to search for transits, and set it looking for this extraordinarily rare event. Since I didn't want to burn months of computing time with nothing to show for it, I decided to prepare a canon of all Solar System transits (excluding marginal graze events) visible in the time interval I chose, namely a quarter million years centred on the start of the so-called “Common Era”. Here it is.
There are about 200 billion stars in our Milky Way galaxy. Over the next million years our descendents will spread among the stars in an exponential explosion of life, remaking the galaxy as surely as life has remolded Earth in its own image. //
Imagine the variety of worlds and wealth of living species flourishing upon them! Water worlds, desert planets, mountains that reach above the sky—every habitat imagined in science fiction will become real, and many more yet to spring from the imagination of world-makers born half a million years from now.
Terranova is a highly premature anticipation of this exhilarating milestone in the endless adventure of life and intelligence. Every day around 11 a.m. Universal Time a new planet is created using random parameters, and an image of it, as seen from the bridge from your approaching starship, is produced.
“If they existed, they would be here”, said Fermi. So where are they? Nowhere in evidence. Intelligent beings with technologies advanced millions of years beyond our own, spread to the far ends of the galaxy, should not be difficult to detect. We already possess the means to detect even primitive technological civilisations like our own at a distance of hundreds of light years.
If they existed, they—the first intelligent species to expand outward among the stars—would be here. And since we look around and see nobody but ourselves, then it is only reasonable to conclude, “We are here, so we are them.”
Image was captured during Martian spring, on May 21, by Mars Reconnaissance Orbiter's HiRISE camera
In Mars' northern hemisphere, the snow and ice seen on the dunes is made of carbon dioxide - or, dry ice
As it reacts to sun, the gas that escapes carries up the dark sand from below, creating 'beautiful patterns'
Here are two options for future humans to keep us in the habitable zone.
The 2024 total eclipse is in the books. Here's how it looked across the US.
And God said, Let there be light: and there was light. And God saw the light, that it was good: and God divided the light from the darkness. And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day."
The steady rhythm of the night-day, dark-light progression is a phenomenon acknowledged in ancient sacred texts as a given. When it's interrupted, people take notice. In the days leading up to the eclipse, excitement within the Ars Orbiting HQ grew, and plans to experience the last total eclipse in the continental United States until 2045 were made. Here's what we saw across the country.
The Flight Data Subsystem was an innovation in computing when it was developed five decades ago. It was the first computer on a spacecraft to use volatile memory. Most of NASA's missions operate with redundancy, so each Voyager spacecraft launched with two FDS computers. But the backup FDS on Voyager 1 failed in 1982.
Due to the Voyagers' age, engineers had to reference paper documents, memos, and blueprints to help understand the spacecraft's design details. After months of brainstorming and planning, teams at JPL uplinked a command in early March to prompt the spacecraft to send back a readout of the FDS memory.
The command worked, and Voyager.1 responded with a signal different from the code the spacecraft had been transmitting since November. After several weeks of meticulous examination of the new code, engineers pinpointed the locations of the bad memory.
"The team suspects that a single chip responsible for storing part of the affected portion of the FDS memory isn’t working," NASA said in an update posted Thursday. "Engineers can’t determine with certainty what caused the issue. Two possibilities are that the chip could have been hit by an energetic particle from space or that it simply may have worn out after 46 years." //
"Although it may take weeks or months, engineers are optimistic they can find a way for the FDS to operate normally without the unusable memory hardware, which would enable Voyager 1 to begin returning science and engineering data again," NASA said.
This website is available as a resource for eclipse and transit records and information, but will not be updated. For the latest on future eclipses from NASA, please visit https://science.nasa.gov/eclipses/
Terry Richardson, Senior Instructor of Astronomy & Physics at the College of Charleston designed a "Make Your Own Safe Solar Viewer" for the upcoming solar eclipse, sunspot cycle 25 and beyond. This set includes our L14810 achromat (52mm diameter by 600mm focal length) and a Barlow lens with a focal length of -27mm. For the achromat: Place the crown (double convex) with its strongest curve against the negative side of the flint. Use a couple pieces of masking tape on the edges to hold them together. The crown side faces the sky. Using an achromat instead of a single element lens you will get to see more of the sunspots and less blue fringe around the sun (chromatic aberration).