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Astronomical News

That just makes it a 'supermoon' — the third in three months — based on a loose definition first coined by an astrologist.
Is this a first? Modern-day astronomy being informed/advised by astrology?
 
Cool your jets, mate. Coining is pretty far removed from informing or advising.
 
Heading out to view this directly. Hope to get some photos but the overcast is quite stubborn at the mo.
Got bupkiss. Damn cloud at the height of summer. Should've been clear, dry and 33. It was overcast, windy and 13. I demand my money back!
 
Cannot see the supermoon, due to damn cloud cover ruining the whole damn show!:frust::frust::frust::frust::frust::frust:
 
Sydney (west of, just a bit!)
 
Adelaide here. I stuck it out on the mountain for two hours. More interested in the lunar eclipse happening currently. Might mosey outside in a mo and see if the red moon is visible yet. It peaks in half an hour.
 
Yeah, wanted to see that, but the clouds, man, the clouds...
 
We've got something. Bit blurry, but we have a definite transition. The disc is about 60% dark. Pretty cool despite being veiled. I'm gonna light a fire and sit out the transition outside.
 
So, something worth being in Adelaide for, then, hey?
 
Ah haha yeah. No, nothing to see here. Adelaide's a hole. You'd hate it. Better stay where you are.

For non-Aussies, you mightn't know (or care ~ the rest of us don't) that people from Sydney and Melbourne are a bit insecure about who's best. They're constantly reminded that their cities don't measure up internationally, so they'll often take a cheap shot at people from other parts of their country to feel better about themselves. It's an east coast neurosis.
 
I've probably mentioned this before, but I did see a literal 'blue moon' back in 1992. That was when an eclipse of the Moon coincided with a major eruption of Mt Pinatubo. The eclipse was very high on the so-called Danjon scale, which measures the amount of darkening.
Here's an image I've found on the internet; the colour I saw was a bit closer to purple, but not much.

 
Ah haha yeah. No, nothing to see here. Adelaide's a hole. You'd hate it. Better stay where you are.

For non-Aussies, you mightn't know (or care ~ the rest of us don't) that people from Sydney and Melbourne are a bit insecure about who's best. They're constantly reminded that their cities don't measure up internationally, so they'll often take a cheap shot at people from other parts of their country to feel better about themselves. It's an east coast neurosis.


No barrels in bank vaults here!
 
I've probably mentioned this before, but I did see a literal 'blue moon' back in 1992. That was when an eclipse of the Moon coincided with a major eruption of Mt Pinatubo. The eclipse was very high on the so-called Danjon scale, which measures the amount of darkening.
Here's an image I've found on the internet; the colour I saw was a bit closer to purple, but not much.

I witnessed a red moon quite without anticipating it in South Korea in 2000 or 2001. Must have been mid to late winter as I slipped on the hard ice walking downhill to work at 6am and crowned myself and nearly dislocated my shoulder. When I was laid out flat on my back, there it was, mooning brownly down at me. I thought I'd broken my brain. So I went home and had the day off.
 
This is worth a watch - The Weirdest Stars in the Universe - lecture by Prof Emily Levesque from the Perimeter Institute For Theoretical Physics, Ontario, from 2 days ago featuring:

Yellow Super Giants
Red Giants
Luminous Blue Variables
Neutron Stars
Pulsars
Black Holes
Gravity Waves
Fast Radio Bursts
Thorne Zytkow Objects [combined neutron/red giant stars]

One slightly mindblowing example: the largest red giant so far discovered, if placed in our solar system, would extend beyond the orbit of Jupiter & towards Saturn.
 
Galaxy without any dark matter baffles astronomers
https://www.theguardian.com/science/2018/mar/28/galaxy-without-any-dark-matter-baffles-astronomers
The absence of dark matter from a small patch of sky might appear to be a non-problem, given that astronomers have never directly observed dark matter anywhere. However, most current theories of the universe suggest that everywhere that ordinary matter is found, dark matter ought to be lurking too, making the newly observed galaxy an odd exception.

“Something like this has never been seen,” said Prof Pieter van Dokkum, of Yale University, the study’s senior author. “It challenges the standard ideas of how we think galaxies form.”

Dark matter’s existence is inferred from its gravitational influence on visible objects, which suggests it dominates over ordinary matter by a ratio of 5:1.

Some of the clearest evidence comes from tracking stars in the outer regions of galaxies, which consistently appear to be orbiting faster than their escape velocity, the threshold speed at which they ought to break free of the gravitational binds holding them in place and slingshot into space. This suggests there is unseen, but substantial, mass holding stars in orbit.

In the Milky Way there is about 30 times more dark matter than normal matter. The latest observations focused on an ultra-diffuse galaxy – ghostly galaxies that are large but have hardly any stars – called NGC 1052-DF2.

The team tracked the motions of 10 bright star clusters and found that they were travelling way below the velocities expected. “They basically look like they’re standing still,” said van Dokkum.

The velocities gave an upper estimate for the galactic mass of 400 times lower than expected. “If there is any dark matter at all, it’s very little,” van Dokkum explained. “The stars in the galaxy can account for all of the mass, and there doesn’t seem to be any room for dark matter.”

Van Dokkum and colleagues identified the galaxy, NGC 1052-DF2, using a low-budget setup called the Dragonfly Telephoto Array in New Mexico, which they designed from 48 commercial cameras and paparazzi-style lenses.

The initial images just showed a ghostly blob on the night sky, but by peering more closely at it using the Gemini Multi Object Spectrograph and Keck telescopes they were able to pick out star clusters within the galaxy and track their movements. The team are now turning to look at other ultra-diffuse galaxies to see whether any others are similarly deficient in dark matter.
3000.jpg
 
Wow... I like that :)

The bright dots travelling from the top of the frame to the bottom, which look something like snow, are in fact background stars. They have that apparent motion as the spacecraft moves and the comet rotates. The more rapidly moving streaks are thought to be dust particles illuminated by the Sun. There also appear to be a few streaking cosmic rays.

So the white flashes in front of the comet would be dust? It's very dusty!
 
Was Venus the first habitable planet in our solar system?
Often referred to as Earth’s evil twin, Venus is the solar system’s hottest planet. But research suggests that Venus may have had vast oceans and a balmy climate
Hannah Devlin Science correspondent
Monday 17 October 2016 11.37 BST

Its surface is hot enough to melt lead and its skies are darkened by toxic clouds of sulphuric acid. Venus is often referred to as Earth’s evil twin, but conditions on the planet were not always so hellish, according to research that suggests it may have been the first place in the solar system to have become habitable.

The study, due to be presented this week at the at the American Astronomical Society Meeting in Pasadena, concludes that at a time when primitive bacteria were emerging on Earth, Venus may have had a balmy climate and vast oceans up to 2,000 metres (6,562 feet) deep.

Michael Way, who led the work at the Nasa Goddard Institute for Space Studies in New York City, said: “If you lived three billion years ago at a low latitude and low elevation the surface temperatures would not have been that different from that of a place in the tropics on Earth,” he said.

The Venusian skies would have been cloudy with almost continual rain lashing down in some regions, however. “So while you might get nice sunsets you would have mostly overcast skies during the day and precipitation,” Way added.

Crucially, if the calculations are correct the oceans may have remained until 715m years ago - a long enough period of climate stability for microbial life to have plausibly sprung up.

“The oceans of ancient Venus would have had more constant temperatures, and if life begins in the oceans - something which we are not certain of on Earth - then this would be a good starting place,” said Way.

Other planetary scientists agreed that, despite the differing fates of the two planets, early Earth and Venus may have been similar.
Professor Takehiko Satoh, who works on the Japan Aerospace Exploration Agency’s Venus Climate Orbiter (“Akatsuki”) mission, said: “Habitable or not, I’m not in a position to answer. Environment-wise, probably Venus once had an ocean and probably the environment of Venus and the Earth might have been similar.”

With an average surface temperature of 462C (864F), Venus is the hottest planet in the solar system today, thanks to its proximity to the sun and its impenetrable carbon dioxide atmosphere, 90 times denser than Earth’s. At some point in the planet’s history this led to a runaway greenhouse effect.

Previous US and Soviet landers sent to Venus have survived only a few hours on the surface before being destroyed.
Way and colleagues simulated the Venusian climate at various time points between 2.9bn and 715m years ago, employing similar models to those used to predict future climate change on Earth. The scientists fed some basic assumptions into the model, including the presence of water, the intensity of the sunlight and how fast Venus was rotating. In this virtual version, 2.9bn years ago Venus had an average surface temperature of 11C (52F) and this only increased to an average of 15C (59F) by 715m years ago, as the sun became more powerful.
More precise measurements of the chemical makeup of Venus’s surface and atmosphere could help establish how much water the planet had in the past, and when this began to disappear.

Some of this information may be filled in by the Akatsuki mission, which is observing the Venusian weather systems in unprecedented detail. The spacecraft was supposed to enter orbit about the planet in 2010, but after its main engine blew out, it instead spent five years drifting around the sun like a miniature artificial planet. Last year, scientists used altitude thrusters to redirect it into an orbit, and the mission could yet answer longstanding questions about our planetary neighbour, including whether it has volcanic activity, whether lightning strikes in the sky and why its atmosphere is rotating 60 times faster than the planet itself.

However, searching for traces of ancient microbial life would need a lander, and would be significantly more challenging.
“It would take a great deal of technology development, and money of course, to build the requisite landing craft to survive the surface conditions of present day Venus and to be able to dig into the surface,” said Way. “But if the investments were made it would be possible to search for such signs of life, including chemical traces.”

Details of the study are also published in the journal Geophysical Research Letters.

https://www.theguardian.com/science/2016/oct/17/was-venus-the-first-habitable-planet-in-our-solar-system

I think we should give up on searching for life (present or past) on the barren desert of Mars and the toxic hothouse of Venus. If outwardly life exist in our solar system the place to look is on the moons of Jupiter or Saturn: Europa, Ganymede, Callisto or Enceladus. Again IMO.
 
It may be that Oumuamua isn't the only object to which we can attribute an extra-solar origin. This story concerns an asteroid whose oddball orbit suggests it may have arrived in, and been captured by, our solar system a few billion years ago.

'Permanent' interstellar visitor found
An asteroid in Jupiter's orbit may have come from outside our Solar System, according to a new study.

Unlike 'Oumuamua, the interstellar object which briefly visited the Solar System earlier this year, 2015 BZ509 (affectionately known as BZ) seems to have been here for 4.5 billion years.

This makes it the first known interstellar asteroid to have taken up residence orbiting the Sun.

It is not yet known where the object came from. ...

FULL STORY: http://www.bbc.com/news/science-environment-44173403
 
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Farting Martians perhaps :)

Curiosity rover sees seasonal Mars methane swing
By Jonathan AmosBBC Science Correspondent
  • 1 hour ago


_101925412_1.jpg
Image copyrightNASA/JPL-CALTECH/MSSS
Image captionThe Curiosity rover carries an onboard lab to measure the chemistry of the atmosphere
It may only be a very small part of Mars' atmosphere but methane waxes and wanes with the seasons, scientists say.

The discovery made by the Curiosity rover is important because it helps narrow the likely sources of the gas.

On Earth, those sources largely involve biological emissions - from wetlands, paddy fields, livestock and the like.

No-one can yet tie a life signature to Mars' methane, but the nature of its seasonal behaviour probably rules out some geological explanations for it.

Etc

https://www.bbc.co.uk/news/science-environment-44405658
 
Where is the methane coming from?
It's a conundrum.
 
More from Mars

Nasa Mars rover finds organic matter in ancient lake bed


Curiosity digs up carbon compounds that could be food for life in sediments that formed 3bn years ago





Nasa’s veteran Curiosity rover has found complex organic matter buried and preserved in ancient sediments that formed a vast lake bed on Mars more than 3bn years ago.

The discovery is the most compelling evidence yet that long before the planet became the parched world it is today, Martian lakes were a rich soup of carbon-based compounds that are necessary for life, at least as we know it.

Researchers cannot tell how the organic material formed and so leave open the crucial question: are the compounds remnants of past organisms; the product of chemical reactions with rocks; or were they brought to Mars in comets or other falling debris that slammed into the surface? All look the same in the tests performed.

But whatever the ultimate source of the material, if microbial life did find a foothold on Mars, the presence of organics meant it would not have gone hungry. “We know that on Earth microorganisms eat all sorts of organics. It’s a valuable food source for them,” said Jennifer Eigenbrode, a biogeochemist at Nasa’s Goddard Space Flight Center in Maryland.

etc

https://www.theguardian.com/science...over-finds-organic-matter-in-ancient-lake-bed
 
Did they find dead fish, I wonder?
 
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