Lucky you! Haven't seen a clear sky in all off January. Here it snowed all day today, we had about 3 inches of snow. Snows just about every day here...Piles of it along the roadside.
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Lucky you! Haven't seen a clear sky in all off January. Here it snowed all day today, we had about 3 inches of snow. Snows just about every day here...Piles of it along the roadside.
From Popular Astronomy, monthly publication
TITAN HAS 'SEA LEVEL' LIKE THE EARTH
NASA
Saturn's moon Titan is nearly a thousand million miles away from the Earth,
but a recently published paper based on data from NASA's Cassini spacecraft
reveals a new way in which Titan and our own planet are similar. Just as the
surfaces of oceans on the Earth lie at an average elevation that we call
'sea level', Titan's seas also lie at an average elevation. That is the
latest finding that shows remarkable similarities between the Earth and
Titan, the only other object that we know of in our Solar System that has
stable liquid on its surface. The twist at Titan is that its lakes and seas
are filled with hydrocarbons rather than with liquid water, and water ice
overlain by a layer of solid organic material serves as the bedrock
surrounding the lakes and seas. The new paper finds that Titan's seas
follow a constant elevation relative to Titan's gravitational pull -- just
like the Earth's oceans. Smaller lakes on Titan, it turns out, appear at
elevations several hundred feet, or metres, higher than Titan's sea level.
Lakes at high elevation are commonly found on Earth. The highest lake
navigable by large ships, Lake Titicaca, has a water volume of nearly 900
cubic kilometres and a surface that is over 3,800 metres above sea level.
The new study of Titan suggests that elevation is important, because Titan's
liquid bodies appear to be connected under the surface in something akin to
a terrestrial aquifer system. Hydrocarbons appear to be flowing underneath
Titan's surface in the way that water flows through underground porous rock
or gravel on Earth, so nearby lakes communicate with each other and share a
common liquid level.
Interesting paper DW. I wonder if thiese hydrocarbons funtion as noutishment for any species.
A curious story:
NASA confirms amateur astronomer has discovered a lost satellite
"Some 12 years since it was thought lost because of a systems failure, NASA’s Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) has been discovered, still broadcasting, by an amateur astronomer. The find, which he reported in a blog post this week, presents the possibility that NASA could revive the mission, which once provided unparalleled views of Earth’s magnetosphere.
The astronomer, Scott Tilley, spends his free time following the radio signals from spy satellites. On this occasion, he was searching in high-Earth orbit for evidence of Zuma, a classified U.S. satellite that’s believed to have failed after launch. But rather than discovering Zuma, Tilley picked up a signal from a satellite labeled “2000-017A,” which he knew corresponded to NASA’s IMAGE satellite. Launched in 2000 and then left for dead in December 2005, the $150 million mission was back broadcasting. It just needed someone to listen."
http://www.sciencemag.org/news/2018/...nasa-satellite
Yes, it is interesting how space projects that we assumed were dead and finished suddenly spring back to life.
Popular Astronomy Monthly Publication 2
SURFACE OF GIANT STAR IMAGED
Georgia State University
Astronomers have produced the first detailed images of the surface of a
giant star, revealing a nearly spherical, dust-free atmosphere with complex
areas of moving material, known as convection cells or granules. The giant
star, named pi1 Gruis, is one of the stars in the southern constellation
Grus. An evolved star in the last major phase of its life, pi1 Gruis is
350 times the size of the Sun and resembles what our Sun will become at the
end of its life in five billion years. Studying that star gives scientists insight about the future activity, characteristics and appearance of the Sun. Convection, the transfer of heat by the bulk movement of gases and liquids, plays a major role in astrophysical processes, such as energy transport, pulsation and winds. The Sun has about two million convective
cells that are typically 2,000 km across, but theorists believe that giant
and supergiant stars should have only a few large convective cells because
of their low surface gravities. Determining the convection properties of
most evolved and supergiant stars, such as the sizes of granules, has been
challenging because their surfaces are frequently obscured by dust. In the
study summarized here, the researchers discovered that the surface of the
giant star pi1 Gruis had a complex convective pattern, and that a typical
granule measured 1.2 x 10^11 metres horizontally or 27% of the diameter of
the star.
This is the first time that astronomers have unambiguously imaged such a
giant star with that level of detail. The reason is that there is a limit
to the details that can be seen, related to the size of the telescope used
for the observations. The team used an interferometer, in which the light
from several telescopes is combined, achieving a resolution equivalent to
that of a much larger telescope. The star pi1 Gruis was observed with the
PIONIER instrument, which has four combined telescopes, in Chile in 2014
September. That study was also the first to confirm theories about the
characteristics of granules on giant stars. The images are important,
because the size and number of granules on the surface actually fitted very
well with models that predict what astronomers should be seeing. The
detailed images also showed different colours on the star's surface, which
correspond to varying temperatures. A star does not have the same surface
temperature throughout, and its surface provides our only clues to under-
stand its interior. As temperatures rise and fall, the hotter, more fluid
areas become brighter colours (whiter) and the cooler, denser areas become
darker (redder).
http://earthsky.org/earth/methane-pu...iomass-burning
EarthSky gave published findings on methane in the atmosphere. This post is well worth reading!
Two very interesting articles, DW. The first is concerned with the materials a giant star is made of. At this point I have the impression that each of the examined celestial bodies has a different composition.
The second about the increase of methane in the atmosphere of the earth examines the biomass burning emissions. I hope they are wrong about the ruminants as a cause of increased methane in the atmosphere.
The EarthSky thread is particularly interesting, many don't think of EarthSky as an astronomy website, but it certainly is.
https://www.universetoday.com/138488...rich-in-water/
The search for life in the universe is clearly on, starting with a neighbouring star.
"When we finally find life somewhere out there beyond Earth, it’ll be at the end of a long search. Life probably won’t announce its presence to us, we’ll have to follow a long chain of clues to find it. Like scientists keep telling us, at the start of that chain of clues is water.
The discovery of the TRAPPIST-1 system last year generated a lot of excitement. 7 planets orbiting the star TRAPPIST-1, only 40 light years from Earth. At the time, astronomers thought at least some of them were Earth-like. But now a new study shows that some of the planets could hold more water than Earth. About 250 times more."
I've now re-read the article "Is Proxima b Habitable"? in Popular Astronomy Jan-Feb 2017 (my one year subscription). It is in the habitable zone of its star the red dwarf Proxima Centauri, so it is in the best goldilocks position for abundant water. Ultra violet radiation may be a problem but there are ways of adapting to it, living underground, in rocks or under water. On Earth there are ways for corals to contain special proteins which absorb harmful UV rays. The next generation of advanced telescopes might be able to detect such biofluorescent glows.
Proxima Centauri is the closest star to the Sun, so it will be interesting to learn what the next generation of advanced telescopes will detect.
Yes. There was a comment on this article in the Brazilian news yesterday and I was going to look for it, but you were faster. Maybe the moment of finding water in another planet isn´t so far away any more.Quote:
Originally Posted by Dreamwoven
In fact I wonder why they haven´t found water yet. Is it indispensable only to us, creatures of the earth?Quote:
Originally Posted by Dreamwoven
And now that:
Humanity’s new star
"You now have nine months to enjoy the recently launched Humanity Star — an artificial satellite designed specifically for maximum visibility from anywhere on the planet over the course of its nine-month orbit. This reflective geodesic sphere was deployed during Rocket Lab’s January 21 Electron rocket launch, which also carried three commercial satellites into space and ushered New Zealand into the growing number of nations capable of reaching Earth orbit.
The Humanity Star is a small sphere about 3 feet (1 meter) in diameter. It’s designed to reflect sunlight from its 65 panels, much like the Iridium satellites reflect light from their flat panels (called Iridium flares). But while Iridium flares are unintentional, the Humanity Star’s reflections are meant to act as a sort of interactive space art piece, with the goal of not only encouraging a sense of planetary community, but also instilling a sense of wonder about the night sky."
http://astronomy.com/news/2018/02/humanitys-new-star
To say we want the moon has long ceased to be a methapher.
It is probably a bit premature to be finding water, all they are claiming is that Proxima b looks to be hopeful for finding water. The next generation of ground-based telescopes will be when they will start looking seriously, Spitzer and James Webb will be ready in 1990, and there are others too.
There is a Swedish song about that, roughly it says "I want to have my own moon, where I can sit and forget about you". The Astronomy now journal comes up with some curious ideas. Who knows, it may capture a few peoples' imaginations and convert some to astronomy.Quote:
Originally Posted by Danik 2016
https://www.universetoday.com/138494...lar-asteroids/
I think this is quite likely, it makes sense.
"Blue Moon" by fado singer Amalia Rodrigues:Quote:
Originally Posted by Dreamwoven
https://www.youtube.com/watch?v=0qqjTtLMRPg
"It would be no exaggeration to say that the discovery of ‘Oumuamua has set off something of a revolution in astronomy. In addition to validating something astronomers have long suspected, it has also provided new opportunities for research and the testing of scientific theories (such as lithopanspermia).
In the future, with any luck, robotic missions will be dispatched to these bodies to conduct direct studies and maybe even sample return missions. What these reveal about our Universe, and maybe even the spread of life throughout, is sure to be very illuminating!"
https://www.universetoday.com/138494...lar-asteroids/
Well, I hope they are cautious with this studies as microbes, where ever they come from, may cause a lot of harm.
A Carnival visitor:
Asteroid to pass between Earth and Moon on Friday
The asteroid, which is between 50 and 130 feet wide, will miss Earth by a distance of 39,000 miles — less than one-fifth the distance between Earth and the Moon.
"On February 4, astronomers using the NASA-funded Catalina Sky Survey (CSS) detected two asteroids with orbits that take them between Earth and the Moon this week. Fortunately, neither object’s trajectory presents a threat to Earth.
In fact, the week’s first visiting asteroid — dubbed asteroid 2018 CC — has already completed its closest approach to Earth. The small rocky body zoomed by our planet on Tuesday, February 6, at 3:10 p.m. EST, just 35 minutes before SpaceX launched their Falcon Heavy rocket. Asteroid 2018 CC, which is estimated to be between 50 and 100 feet (15 and 30 meters) wide, came within about 114,000 miles (184,000 kilometers) of Earth.
On the other hand, the potentially more interesting asteroid — named asteroid 2018 CB — will pass by Earth on Friday, February 9, at around 5:30 p.m. EST. With an estimated size of between 50 and 130 feet (15 and 40 meters), this asteroid is not just larger than 2018 CC, but it also passes much closer to our planet. Asteroid 2018 CB will skirt by Earth at a distance of 39,000 miles (64,000 km), bringing it five times closer to us than the Moon. "
http://www.astronomy.com/news/2018/0...arth-on-friday
Thanks for that, Danik, very interesting.
https://www.universetoday.com/138516...civilizations/
The search for extra-terrestrial intelligence (SETI) continues:
“We searched for signals that are narrow (< 10 Hz) in the frequency domain,” said Margot. “Such signals are technosignatures because natural sources do not emit such narrowband signals… We identified approximately 850,000 candidate signals, of which 19 were of particular interest. Ultimately, none of these signals were attributable to an extraterrestrial source.”
You can read the whole post for the complete picture.
Amazing, DW! The article can be downloaded in pdf. It might interest you and such Litnetters that are comfortable with mathematical data analysis like Yes/No and desirejab.
A SEARCH FOR TECHNOSIGNATURES FROM 14 PLANETARY SYSTEMS IN THE KEPLER
FIELD WITH THE GREEN BANK TELESCOPE AT 1.15{1.73 GHZ
ABSTRACT
"Analysis of Kepler mission data suggests that the Milky Way includes billions of Earth-like planets
in the habitable zone of their host star. Current technology enables the detection of technosignatures
emitted from a large fraction of the Galaxy. We describe a search for technosignatures that is sensitive
to Arecibo-class transmitters located within 450 ly of Earth and transmitters that are 1000 times
more eective than Arecibo within 14 000 ly of Earth. Our observations focused on 14 planetary
systems in the Kepler eld and used the L-band receiver (1.15{1.73 GHz) of the 100 m diameter
Green Bank Telescope. Each source was observed for a total integration time of 5 minutes. We
obtained power spectra at a frequency resolution of 3 Hz and examined narrowband signals with
Doppler drift rates between 9 Hz s��1. We
agged any detection with a signal-to-noise ratio in
excess of 10 as a candidate signal and identied approximately 850 000 candidates. Most (99%) of
these candidate signals were automatically classied as human-generated radio-frequency interference
(RFI). A large fraction (>99%) of the remaining candidate signals were also
agged as anthropogenic
RFI because they have frequencies that overlap those used by global navigation satellite systems,
satellite downlinks, or other interferers detected in heavily polluted regions of the spectrum. All
19 remaining candidate signals were scrutinized and none could be attributed to an extraterrestrial
source.
Keywords: astrobiology|extraterrestrial intelligence|planets and satellites: general
| (stars: planetary systems | techniques: spectroscopic
Corresponding author: Jean-Luc Margot
[email protected]
arXiv:1802.01081v1"
Are we heading in the direction of radiocomunication with ETs?
I have been returning to the question of searching for extra-terrestrial intelligence.
See https://astronomynow.com/2016/03/03/...-sky-location/
https://www.seti.org
is the website concerned fully with this issue.
The cosmology topic that YesNo started (and that I contributed to some time ago now) is thriving with desiresjab involved. I'm very glad to see this!
Artificial or natural intelligence in other planets: its a dream that may come true but Iam not sure wheter we are going to like what we discover.Quote:
Originally Posted by Dreamwoven
The cosmology thread seems to be starting to discuss the future of humankind on this planet. This is where cosmology and astronomy appear to be meeting. The 2 posts in astronomy now and universe today the I gave links for above is not a coincidence. The Carl Sagan Center and the CETI Institute - https://www.seti.org/node/647 - are two nodes the come together.
No, I agree with you. We will see, I guess.
I definitely don´t like that information:
Viruses -- lots of them -- are falling from the sky
Date:
February 6, 2018
Source:
University of British Columbia
Summary:
An astonishing number of viruses are circulating around the Earth's atmosphere -- and falling from it -- according to new research. The study marks the first time scientists have quantified the viruses being swept up from the Earth's surface into the free troposphere, beyond Earth's weather systems but below the stratosphere where jet airplanes fly. The viruses can be carried thousands of kilometers there before being deposited back onto the Earth's surface.
https://www.sciencedaily.com/release...0206090650.htm
I wonder what the viruses are, what illnesses they are from. Horrid!
I don´t know if all of them are that harmful. But it seems to me that the idea, that all viruses where generated on earth is changing. That caught my attention in this article.
NASA releases record-breaking photos from beyond Pluto
In two hours, New Horizons smashed a 27-year-old record set by Voyager 1 … twice.
http://www.astronomy.com/news/2018/0...m-beyond-pluto
Yes, these record-breaking images presage the even more record-breaking images that we will see once the next target comes into view in early 2019.
We have only seen the next imagers as blurs, but you can tell there are several objects including probably one moon. Out there in the Kuiper Belt gravity is much weaker.
http://earthsky.org/space/interstell...e-violent-past
"The strange interstellar visitor to our solar system – dubbed ‘Oumuamua´ by astronomers – is tumbling as it moves through space. A new study suggests its chaotic tumble is likely to continue at least another billion years, and it suggests ‘Oumuamua’s tumble is the result of a violent collision with another asteroid in the past. This collision might have knocked ‘Oumuamua out of its original solar system and sent it toward our solar system.
Astronomer Wes Fraser of Queen’s University in Kingston, Ontario, Canada, led this new research. Fraser and his team analyzed all the available data from optical photometry; that is, they looked at the data on how ‘Oumuamua’s brightness varied over time. Then they used computer modeling to understand why ‘Oumuamua varied in brightness, and to spin out reasonable possibilities for its past and future. Their study was published in the peer-reviewed journal Nature Astronomy on February 9, 2018."
Stunning pictures of Jupiter (Juno Mission)
https://www.vox.com/science-and-heal...ew-photos-juno
Yes, very nice!
A new monthly number of astronomy posts:
The SOCIETY for POPULAR ASTRONOMY
Electronic News Bulletin No. 463 2018 February 18
Here is the latest round-up of news from the Society for Popular
Astronomy.
DOUBT CAST ON EVOLUTION OF MARTIAN LIFE
The University of Hong Kong
"Mars has long been of interest as a place to search for evidence of life
beyond the Earth, because the surface has numerous features that appear to be dried-up river channels and dried lake beds that hint at a warmer,
wetter, more-Earthlike climate in the past. However, new research has cast
doubt on the idea of surface life evolving on Mars. For the last 2.5
billion years, surface life on Earth has thrived largely through the
evolution of photosynthesis. Surface life is abundant and very successful
because of the availability of sunlight, surface water, generally moderate
climate conditions, and the protection of our magnetic field. But Mars would never
have experienced such habitable conditions at the surface.
Now scientists show that the climate of Mars has probably been extremely cold and dry most of the time. They argue that the familiar aqueous features on Mars include widespread, weathered soil horizons that could have formed in 'geologically' short climate 'excursions'. In other words, Mars has been cold and dry almost throughout its history and has only had abundant liquid water on its surface during relatively short episodes of climate change. However, all hope for life on Mars is not lost. The scientists point out that the prospects for surface life on Mars might be dim, but the possibilities for sub-surface life are promising. Life on Earth probably began in hydrothermal systems (environments where hot water reacts with rocks), and there is abundant evidence for many locations where hydrothermal environments existed on Mars at the time when life might have originated in similar environments on Earth. The scientists argue that, in order to understand how life formed on Earth, we should ignore the surface environments on Mars and focus exploration on hydrothermal deposits. Using infrared data on Mars collected by spacecraft, astronomers can interpret which minerals are there and describe the 'geology' of ancient hydrothermal systems. That type of work is based on laboratory measurements, which provide the necessary mineralogical background with which to interpret spectroscopic data from Mars."