Astronomy

Speaking about salad, Here is an interesting link about Astronaut food:

https://airandspace.si.edu/exhibitio...d-in-space.cfm

https://www.universetoday.com/138308...solar-planets/

The study of exoplanets has advanced by leaps and bounds in the past few decades. Between ground-based observatories and spacecraft like the Kepler mission, a total of 3,726 exoplanets have been confirmed in 2,792 systems, with 622 systems having more than one planet (as of Jan. 1st, 2018). And in the coming years, scientists expect that many more discoveries will be possible thanks to the deployment of next-generation missions.

These include NASA's James Webb Space Telescope (JWST) and several next-generation ground based observatories. With their advanced instruments, these and other observatories are not only expected to find many more exoplanets, but to reveal new and fascinating things about them. For instance, a recent study from Columbia University indicated that it will be possible, using the Transit Method, to study surface elevations on exoplanets.

Interesting study. I´m sure that the surface of the exoplanets has a lot to teach us.

I´m glad you are back, DW. Other Litnetters are also having posting issues.

Thank you Danik. I am going to revert to fewer posts, until we get more useful posts that can generate discussion.

That´s ok with me. Fewer posts are easier to follow up.

http://astronomy.com/magazine/press-...on-of-a-planet

We do have very inadequate definitions of what a planet is:

See this:
"Pluto hogs the spotlight in the continuing scientific debate over what is and what is not a planet, but a less conspicuous argument rages on about the planetary status of massive objects outside our solar system. The dispute is not just about semantics, as it is closely related to how giant planets like Jupiter form."

"Johns Hopkins University astrophysicist Kevin Schlaufman aims to settle the dispute.

In a paper just published in the Astrophysical Journal, Schlaufman has set the upper boundary of planet mass between four and 10 times the mass of the planet Jupiter. The paper is online in the journal at: http://iopscience.iop.org/article/10...38-4357/aa961c. It is also archived at: https://arxiv.org/abs/1801.06185."

See also this discussion on EarthSky

http://earthsky.org/space/new-planet...-johns-hopkins

Interesting discussion, DW. In the light of the new discoveries of celestial bodies, the traditional definitions of "planet" and "star" one learnt at school have become obsolete. An important stage of the discussion happened in 2006 when Pluto was declared to be a dwarf planet. Before that the concept of dwarf planet didn´t exist.
Still I think new definitions of the concept of "planet" at this moment can only be tentatively. New discoveries are being made dayly.

Yes, quite. Someone should tell the gaffers and gammers who decide the new definitions, that their attempt to update the old definitions is already out of date. Especially the claim that planets have their own cleared path.

Something that happens today in all fields of knowledge I suppose is a thirst for visibility, specially in the social medias. Of course many of the researches are serious. But from all the articles that we have been reading about Astronomy only one thing seems to be sure: Astronomy is experiencing a boom of dicoveries, due to the perfectioning of their tools and space ships. Probably there is still much more ahead. And all this will take much time to sort out and conceptualize.
Yesterday in the soap opera one lover told his girl friend: the stars are many, but the moon is unique. No more! The moon only was unique as long as we didn´t know about the other ones.

A controversial theme:
The hunt for viruses in space

You’ve probably heard of the field of astrobiology, but what about the field of astrovirology?

To date, almost no research has looked into the possibility of viruses “living” in space or on other worlds. But now, Portland State University biology professor Ken Stedman wants to kick-start the search.

According to an article published in the February 2018 issue of Astrobiology, Stedman and his colleagues argue that it's time for astronomers to broaden their cosmic search for life by also combing space for viruses. “More than a century has passed since the discovery of the first viruses,” said Stedman, “entering the second century of virology, we can finally start focusing beyond our own planet.”

http://www.astronomy.com/news/2018/0...ruses-in-space

That's true (#1585). And we still have not discovered - still less explored - many of the moons in this, our solar system. It is possible too, that in the Kuiper Belt, once New Horizons gets to the next Kuiper Belt objects (in about a year's time!) that they will find another moon.

The role played by citizen cientists deserves to be discussed I think

Citizen scientists discover new exoplanet system named K2-138

"Four new planets orbiting a distant star have been discovered by citizen scientists around the world, a report has revealed.

Researchers discovered the K2-138 planetary system, home to at least five “sub-Neptune” planets between the size of Earth and Neptune, nearly 620 light years from Earth.

The exoplanet family was discovered after researchers launched a crowdsourcing project to help sift through three years’ worth of data from 280,000 stars."
http://www.independent.co.uk/news/sc...-a8169471.html

Interesting. Somehow the crowdsourcing project gave the project access to Hubble. I wonder how this was practically done?

Here the project is explained in more details:
"Enter the Exoplanet Explorers citizen scientist project, developed by UC Santa Cruz astronomer Ian Crossfield and Caltech staff scientist Jessie Christiansen. Exoplanet Explorers is hosted on Zooniverse, an online platform for crowdsourcing research.

"People anywhere can log on and learn what real signals from exoplanets look like, and then look through actual data collected from the Kepler telescope to vote on whether or not to classify a given signal as a transit, or just noise," says Christiansen. "We have each potential transit signal looked at by a minimum of 10 people, and each needs a minimum of 90 percent of 'yes' votes to be considered for further characterization."

In early April, just two weeks after the initial prototype of Exoplanet Explorers was set up on Zooniverse, it was featured in a three-day event on the ABC Australia television series Stargazing Live. In the first 48 hours after the project was introduced, Exoplanet Explorers received over 2 million classifications from more than 10,000 users. Included in that search was a brand-new dataset from the K2 mission—the reincarnation of the primary Kepler mission, ended three years ago. K2 has a whole new field of view and crop of stars around which to search for planets. No professional astronomer had yet looked through this dataset, called C12.

Back in California, Crossfield and Christiansen joined NASA astronomer Geert Barentsen, who was in Australia, in examining results as they came in. Using the depth of the transit curve and the periodicity with which it appears, they made estimates for how large the potential planet is and how close it orbits to its star. On the second night of the show, the researchers discussed the demographics of the planet candidates found so far—44 Jupiter-sized planets, 72 Neptune-sized, 44 Earth-sized, and 53 so-called Super Earth's, which are larger than Earth but smaller than Neptune.

"We wanted to find a new classification that would be exciting to announce on the final night, so we were originally combing through the planet candidates to find a planet in the habitable zone—the region around a star where liquid water could exist," says Christiansen. "But those can take a while to validate, to make sure that it really is a real planet and not a false alarm. So, we decided to look for a multi-planet system because it's very hard to get an accidental false signal of several planets."

After this decision, Barentsen left to get a cup of tea. By the time he returned, Christiansen had sorted the crowdsourced data to find a star with multiple transits and discovered a star with four planets orbiting it. Three of the four planets had 100 percent "yes" votes from over 10 people, and the remaining one had 92 percent "yes" votes. This is the first multi-planet system of exoplanets discovered entirely by crowdsourcing.

After the discovery was announced on Stargazing Live, Christiansen and her colleagues continued to study and characterize the system, dubbed K2-138. They statistically validated the set of planet signals as being "extremely likely," according to Christiansen, to be signals from true planets. They also found that the planets are orbiting in an interesting mathematical relationship called a resonance, in which each planet takes almost exactly 50 percent longer to orbit the star than the next planet further in. The researchers also found a fifth planet on the same chain of resonances, and hints of a sixth planet as well. A paper describing the system has been accepted for publication in The Astronomical Journal.

This is the only system with a chain of unbroken resonances in this configuration, and may provide clues to theorists looking to unlock the mysteries of planet formation and migration.

"The clockwork-like orbital architecture of this planetary system is keenly reminiscent of the Galilean satellites of Jupiter," says "What's exciting is that we found this unusual system with the help of the general public."

The paper is titled "The K2-138 system: A Near-Resonant Chain of Five Sub-Neptune Planets Discovered by Citizen Scientists." In addition to Christiansen, Crossfield, and Barentsen; other coauthors include Chris Lintott, Campbell Allen, Adam McMaster, Grant Miller, Martin Veldthuis of the University of Oxford; Thomas Barclay of NASA Goddard and the University of Maryland; Brooke Simmons of UC San Diego; Caltech postdoctoral scholar Erik Petigura; Joshua Schlieder of NASA Goddard; Courtney Dressing of UC Berkeley; Andrew Vanderburg of Harvard; Sarah Allen and Zach Wolfenbarger of the Adler Planetarium; Brian Cox of the University of Manchester; Julia Zemiro of the Australian Broadcasting Corporation; Caltech Professor of Astronomy Andrew Howard; John Livingston of the University of Tokyo; Evan Sinukoff of the Australian Broadcasting Corporation and the University of Hawai'i at Manoa; Timothy Catron of Arizona State University; Andrew Grey, Joshua Kusch, Ivan Terentev, and Martin Vales of Zooniverse as part of the University of Oxford; and Martti Kristiansen of the Technical University of Denmark. Funding was provided by the NASA Science Mission Directorate, Google, the Alfred P. Sloan Foundation, NASA, the National Science Foundation, the U.S. Department of Energy, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England.

Written by Lori Dajose
Contact:
Whitney Clavin
(626) 395-1856
[email protected]
CALIFORNIA INSTITUTE OF TECHNOLOGY1200 EAST CALIFORNIA BOULEVARD, PASADENA, CALIFORNIA 91125Site co"

http://www.caltech.edu/news/citizen-...t-system-80989

But the citizen scientists weren´t included in the credits it seems. Anyway it is a new form of scientific research and it may well become the science method in future, as cultural products seem to get more and more massified.