Astronomers trace massive cosmic explosion back 12 billion years. 'This is the most distant event where we can directly see light escaping from around stars'. Via @spacedotcom #Space #Astrophysics #OrbitalMechanics #Astronomy 🚀 🌌 ☄️ 🛰️
Astronomers trace massive cosm...
astronomy
Crazy About Those Martians!
The first Martian craze was not in the 1950's, but started in 1877.
https://blogs.loc.gov/loc/2025/08/look-you-can-see-the-martians-or-maybe-not/
Books by Giovanni Schiaparelli at PG:
https://www.gutenberg.org/ebooks/author/2523
Map of Mars by Giovanni Schiaparelli
The world is getting brighter. From astronomy to bird migration, we explore how growing levels of artificial light are impacting our ecosystem and the effort to preserve dark skies. It’s “Don’t Lighten Up” on Big Picture Science.
Listen here: https://bigpicturescience.org/episodes/dont-lighten-up
Halley's Comet won't reappear until 2061, but Pons-Brooks is a similar big, long-period comet putting -- and it's putting on a show *right now*.
You'll need good binoculars, but oh is it pretty. Photo taken on Monday by Michael Jäger.
https://theskylive.com/12p-info
#astronomy #space #science #comet #photography
#OTD in 1781. The planet Uranus was discovered.
English astronomer William Herschel observed the seventh planet from the Sun, Uranus—first described by him as “a curious either nebulous star or perhaps a comet” and named for the father of the god Saturn. With a homemade 6.2-inch reflecting telescope, Herschel "engaged in a series of observations on the parallax of the fixed stars."
Books about Herschel at PG:
https://gutenberg.org/ebooks/search/?query=William+Herschel&submit_search=Go%21
Edited 1y ago
Don’t fuck with moon dust. No seriously, do not fuck with moon dust.
Absent any moisture or atmosphere, millennia of asteroid impacts have turned lunar regolith (soil) into a fine powder of razor sharp, glass-like particles. What’s more, the solar wind imparts an electric charge on the dust, causing it to cling to any and every surface it touches through static electricity. On earth, sand tends to get smoother over time as wind and water tumble the grains about, eroding their sharpness. Not so on the moon – lunar dust is sharp and deadly. This is Not A Good Time if you’re an explorer looking to visit our celestial neighbor.
During Apollo, the astronauts faced a plethora of unexpected issues caused by dust. It clung to spacesuits and darkened them enough that exposure to sunlight overheated the life support systems. Dust got in suit joints and on suit visors, damaging them. It ate away layers of boot lining. It covered cameras. Upon returning to the cabin, astronauts attempting to brush it off damaged their suit fabric and sent the dust airborne, where it remained suspended in the air due to low gravity.
Inhaling moon dust causes mucus membranes to swell; every Apollo astronaut who stepped foot on the moon reported symptoms of “Lunar Hay Fever.” Sneezing, congestion, and a “smell of burnt gunpowder” took days to subside. Later Apollo missions even sent a special dust brush with the team to help clean each other and equipment. We don’t know exactly how dangerous the stuff is, but lunar regolith simulants suggest it might destroy lung and brain cells with long-term exposure. 1
In fact the dust is so nasty that it destroyed the vacuum seals of sample return containers. We no longer have any accurate samples of lunar dust, “Every sample brought back from the moon has been contaminated by Earth’s air and humidity […] The chemical and electrostatic properties of the soil no longer match what future astronauts will encounter on the moon.” 2
Whats worse, the solar-charged dust gets thrown up off the moon’s surface via electrostatic forces. The moon doesn’t technically have an atmosphere, but it does have a thin cloud of sharp dust itching to cling to anything it can find.
And it probably isn’t just the moon. “A 2005 NASA study listed 20 risks that required further study before humans should commit to a human Mars expedition, and ranked "dust" as the number one challenge.” 3
The coolest solution I’ve heard about in next-gen spacesuit design is a mesh of woven wires layered into the suit. When activated, the wire mesh would form an anti-static electric field that repels dust. Quite literally a force field. 4
#astronomy #apollo #moon #lunardust
Did you know we have a remote observatory on Mars?
When NASA's Perseverance rover isn't busy studying the Martian landscape, it turns its gaze upward to do a little skygazing. This is its view of Mars's inner moon, Phobos.
https://mars.nasa.gov/mars2020/mission/status/410/things-that-go-bump-in-the-night-on-mars/ #science #astronomy #astrodon #NASA
The Event Horizon Telescope has unveiled how Sagittarius A*, the supermassive black hole at the centre of our galaxy, looks like in polarised light, which tells us a lot about the magnetic field around this monster.
The lines overlaid on the image below mark the orientation of the polarisation, from which astronomers can work out the structure of the magnetic field around the black hole.
More details: https://www.eso.org/public/news/eso2406/
📷 EHT Collaboration
The astronauts aboard the ISS were amazed by the April 8 solar eclipse, just like the rest of us, and went crazy snapping photos from orbit.
They got some amazing views of the Moon's shadow sweeping across southern Canada & Maine, seen from 420 km (261 miles) above: https://www.flickr.com/photos/nasa2explore/with/53645140833 #space #eclipse #space #astronomy
American astronomer Annie Jump Cannon died #OTD in 1941.
Cannon developed a system of stellar classification based on spectral characteristics, which became known as the Harvard Classification Scheme (she was one of the "Harvard Computers"). She classified hundreds of thousands of stars, organizing them by temperature and spectral characteristics. Her work laid the foundation for our understanding of stellar evolution and the composition of stars.
![Annie Jump Cannon at her desk at the Harvard College Observatory.
Description: First hired by Harvard College Observatory to carry out astronomical calculations, Annie Jump Cannon (1863-1941) eventually became one of the foremost American astronomers, known especially for her work on variable stars. This photograph shows her at her desk at the observatory. Creator/Photographer: Unidentified photographer Medium: Black and white photographic print Persistent URL: [1] Repository: Smithsonian Institution Archives Accession number: SIA2008-0647](/proxy/post_attachment/160685/47d947fcef.jpg "Annie Jump Cannon at her desk at the Harvard College Observatory.
Description: First hired by Harvard College Observatory to carry out astronomical calculations, Annie Jump Cannon (1863-1941) eventually became one of the foremost American astronomers, known especially for her work on variable stars. This photograph shows her at her desk at the observatory. Creator/Photographer: Unidentified photographer Medium: Black and white photographic print Persistent URL: [1] Repository: Smithsonian Institution Archives Accession number: SIA2008-0647")
French astronomer Charles Messier died #OTD in 1817.
He is best known for his catalog, the Messier Catalog (contains 110 objects), which lists various astronomical objects, including nebulae, star clusters, and galaxies. Messier was primarily interested in comet hunting, and his catalog was created to help him and other astronomers differentiate between permanent celestial objects and comets, which could easily be mistaken for new discoveries.
English astronomer Edward W. Maunder was born #OTD in 1851.
The Maunder Minimum, named after him, refers to a period of low solar activity that occurred from about 1645 to 1715. During this time, very few sunspots were observed, indicating a decrease in solar magnetic activity. His research into historical records of sunspot observations led to the recognition of this extended period of solar quiescence, which is now associated with a decrease in global temperatures on Earth.
#OTD in 1910.
Halley's comet reappears after 76 years, and Mark Twain dies at his home, Stormfield, the day after the comet's perihelion. In his autobiography, Twain wrote, "I came in with Halley's comet in 1835. It's coming again next year (1910), and I expect to go out with it. The Almighty has said no doubt, 'Now here are these two unaccountable freaks; they came in together, they must go out together.'"
An Ancient Greek Philosopher Was Exiled for Claiming the Moon Was a Rock, Not a God
2,500 years ago, Anaxagoras correctly determined that the rocky moon reflects light from the sun, allowing him to explain lunar phases and eclipses
By David Warmflash via @SmithsonianMag
Edited 1y ago
Wooooaaahhhh!
The new JWST image of a small bit of the Horsehead Nebula is INCREDIBLE.
To give you a sense of scale here, here’s an image of the nebula from my backyard. That small white box … that’s the JWST field of view! 🤯🤯🤯
Look at ALL those galaxies, all in that tiny white box.
JWST image credit: ESA/Webb, NASA, CSA, K. Misselt and A. Abergel. [updated]
Dodgy image with white boxes is my own.
#JWST #SpaceTelescope #HorseheadNebula #Astronomy #Galaxies #Astrodon
Edited 1y ago
Euclid telescope: A scientist tells us of his quest to understand the nature of dark matter and dark energy.
On July 1st 2023, Euclid, a unique European space telescope was launched from Cape Canaveral. Euclid is the next big step forward in our quest to try to understand the Universe.
By Henk Hoekstra. via @FR_Conversation
Edited 1y ago
A mind-blower for a Friday evening:
This deceptively simple-looking graph is a spectrum of *gravitational waves* ringing through the Milky Way.
The waves may be caused by a chorus of supermassive black holes colliding all across the universe. Whoa!
https://arxiv.org/abs/2306.16227 #science #space #physics #astronomy
#OTD in 1715.
A total solar eclipse is visible across northern Europe and northern Asia, as predicted by Edmond Halley to within four minutes accuracy. He also drew a predictive map showing the path of totality across Great Britain. The original map was about 20 miles off the observed eclipse path, mainly due to his use of inaccurate lunar ephemeris. After the eclipse, he corrected the eclipse path, and added the path and description of the 1724 total solar eclipse.
Scottish astronomer Williamina Paton Stevens Fleming was born #OTD in 1857.
Fleming's most significant contributions came in the field of stellar classification. She developed a system for classifying stars based on their spectra, which became known as the Harvard Classification Scheme. In 1890, she published the first catalog of stellar spectra, which contained over 10,000 stars classified according to her system.
https://en.wikipedia.org/wiki/Stellar_classification#Harvard_spectral_classification
#Aurora photos from my husband a couple of hours ago, outside our home in #Dundee, #Scotland. #AuroraBorealis #NorthernLights #Tayside #Angus #Scotland #Astronomy #Space
Edited 1y ago
#OTD in 1618.
Johannes Kepler confirms his previously rejected discovery of the third law of planetary motion (he first discovered it on March 8 but soon rejected the idea after some initial calculations were made).
The elliptical orbits of planets were indicated by calculations of the orbit of Mars. The third law expresses that the farther a planet is from the Sun, the slower its orbital speed, and vice versa.
https://en.wikipedia.org/wiki/Kepler%27s_laws_of_planetary_motion
#OTD in 1902.
Greek archaeologist Valerios Stais discovers the Antikythera mechanism, an ancient mechanical analog computer.
The mechanism is composed of at least 30 bronze gears housed in a wooden frame. It features dials, pointers, and inscriptions that correspond to various astronomical cycles. The front dial is believed to show the zodiac and the solar and lunar calendars, while the back dials include the Metonic, Saros & Callippic cycles.
French astronomer Benjamin Valz was born #OTD in 1787.
He had a particular interest in comets, his observations including that of Biela’s Comet made in 1846 in which he noted that the comet had split into two parts. He is also remembered for his suggestion that observed irregularities in the orbit of Halley’s Comet may have been due to the gravitational effects of an as-yet unknown planet orbiting the Sun beyond Uranus which was at a time prior to the discovery of Neptune.
English amateur astronomer Richard Christopher Carrington was born #OTD in 1826.
In 1859 his astronomical observations demonstrated the existence of solar flares as well as suggesting their electrical influence upon the Earth & its aurorae; and whose 1863 records of sunspot observations revealed the differential rotation of the Sun. His publications include Results of Astronomical Observations Made at the Observatory of the University, Durham; & Observations of the Spots on the Sun.
#OTD in 1919.
Albert Einstein's theory of general relativity is tested by Arthur Eddington and Andrew Claude de la Cherois Crommelin.
The Eddington experiment was organised by the astronomers Frank Watson Dyson & Arthur Stanley Eddington in 1919. The observations were of the total solar eclipse of 29 May 1919 and were carried out by two expeditions which aim was to measure the gravitational deflection of starlight passing near the Sun.
