Astronomy recent news update


This January 2017 video is called Top 10 Recently Discovered Earth Like Planets.

Kepler shows small exoplanets are either super-Earths or mini-Neptunes. Tally from the prolific space telescope adds 10 more potentially habitable rocky planets to count. By Lisa Grossman, 6:39pm, June 19, 2017: here.

Life might have a shot on planets orbiting dim red stars. If exoplanets around M dwarfs host life, it’s probably very different from that on Earth. By Christopher Crockett, 10:00am, June 14, 2017.

Eclipse watchers catch part of the sun’s surface fleeing to space. Spectrometer designed to measure speed, temperature and more to be deployed during U.S. eclipse in August. By Lisa Grossman, 2:57pm, June 16, 2017.

See the latest stunning views of Jupiter. The Juno spacecraft whizzes by once every 53 days. By Emily DeMarco, 9:00am, June 16, 2017.

Astronomy news


This video from the USA says about itself:

First Science From Juno at Jupiter (NASA News Audio with Visuals)

Scientists from NASA’s Juno mission to Jupiter discussed their first in-depth science results in a media teleconference on May 25, 2017, at 2 p.m. ET (11 a.m. PT, 1800 UTC), when multiple papers with early findings were published online by the journal Science and Geophysical Research Letters.

The teleconference participants were:

Diane Brown, program executive at NASA Headquarters in Washington
Scott Bolton, Juno principal investigator at Southwest Research Institute in San Antonio
Jack Connerney, deputy principal investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland
Heidi Becker, Juno radiation monitoring investigation lead at NASA’s Jet Propulsion Laboratory in Pasadena, California
Candy Hansen, Juno co-investigator at the Planetary Science Institute in Tucson, Arizona

Juno launched on Aug. 5, 2011, from Cape Canaveral Air Force Station, Florida, and arrived in orbit around Jupiter on July 4, 2016. In its current exploration mission, Juno soars low over the planet’s cloud tops, as close as about 2,100 miles (3,400 kilometers). During these flybys, Juno probes beneath the obscuring cloud cover of Jupiter and studies its auroras to learn more about the planet’s origins, structure, atmosphere and magnetosphere.

For more information about the Juno mission, visit here.

Jupiter’s precocious birth happened in the solar system’s first million years. Early formation date may explain our oddball planetary lineup. By Lisa Grossman, 3:01pm, June 12, 2017.

Water circling a drain provides insight into black holes. Energy boost from rotational superradiance detected for the first time. By Emily Conover, 11:00am, June 12, 2017.

Swift kick from a supernova could knock a black hole askew. Gravitational wave detection hints at unexpected power from star explosion. By Emily Conover, 2:37pm, June 9, 2017.

Astronomical research news


This video says about itself:

7 June 2017

Albert Einstein reshaped our understanding of the fabric of space. In his general theory of relativity in 1915, he proposed the revolutionary idea that massive objects warp space, due to the effects of gravity. Until that time, Isaac Newton‘s theory of gravity from two centuries earlier held sway: that space was unchanging.

Einstein’s theory was experimentally verified four years later when a team led by British astronomer Sir Arthur Eddington measured how much the sun’s gravity deflected the image of a background star as its light grazed the sun during a solar eclipse.

Astronomers had to wait a century, however, to build telescopes powerful enough to detect this gravitational warping phenomenon caused by a star outside our solar system. The amount of deflection is so small only the sharpness of the Hubble Space Telescope could measure it. Hubble observed the nearby white dwarf star Stein 2051 B as it passed in front of a background star. During the close alignment, the white dwarf’s gravity bent the light from the distant star, making it appear offset by about 2 milliarcseconds from its actual position. This deviation is so small that it is equivalent to observing an ant crawl across the surface of a quarter from 1,500 miles away.

Einstein’s light-bending by single far-off star detected. Famous effect of general relativity provides accurate mass of distant white dwarf. By
Lisa Grossman, 11:15am, June 7, 2017: here.

See also here.

Milky Way’s loner status is upheld. Galaxy’s location in a vast cosmic void could help explain dueling universe expansion rates. By
Lisa Grossman, 5:47pm, June 7, 2017: here.

Very hot planet discovered


This video says about itself:

KELT-9b – the hottest giant exoplanet

5 June 2017

650 light years away from Earth, in the constellation Cygnus, astronomers discovered a Jupiter-mass gas giant: KELT-9b. The exoplanet has a dayside temperature estimated around 4300 degrees Celsius. KELT-9b is hotter than most stars and only about 1000 degrees cooler than the Sun.

From Science News:

Scalding hot gas giant breaks heat records

KELT 9b’s temps soar higher than many stars

By Maria Temming

11:00am, June 5, 2017

The planet KELT 9b is so hot — hotter than many stars — that it shatters gas giant temperature records, researchers report online June 5 in Nature.

This Jupiter-like exoplanet revolves around a star just 650 light-years away, locked in an orbit that keeps one side always facing its star. With blistering temps hovering at about 4,300o Celsius, the atmosphere on KELT 9b’s dayside is over 700 degrees hotter than the previous record-holder — and hot enough that atoms cannot bind together to form molecules.

“It’s like a star-planet hybrid,” says Drake Deming, a planetary scientist at the University of Maryland in College Park who was not involved in the research. “A kind of object we’ve never seen before.”

KELT 9b also boasts an unusual orbit, travelling around the poles of its star, rather than the equator, once every 36 hours. And radiation from KELT 9b’s host star is so intense that it blows the planet’s atmosphere out like a comet tail — and may eventually strip it away completely.

The planet is so bizarre that it took scientists nearly three years to convince themselves it was real, says Scott Gaudi of Ohio State University. Deming suspects KELT 9b is “the tip of the iceberg” for an undiscovered population of scalding-hot gas giants.

Astronomy update


This video says about itself:

Backyard Worlds: The Search For Planet 9

15 February 2017

Citizen scientists join the search for Planet 9. Backyard Worlds enlists amateurs to look for celestial objects. By Ashley Yeager, 7:00am, May 29, 2017: here.

Why you can hear and see meteors at the same time. Radio waves may explain the mysterious phenomenon. By Thomas Sumner, 7:00am, May 30, 2017: here.

‘Oxygen on comet 67P not that ancient’


This 8 May 2017 video is called Study Suggests Alternative For Oxygen Formation On Comets.

From Science News:

Oxygen on comet 67P might not be ancient after all

Newly discovered chemical reaction could generate the gas instead, study suggests

By Ashley Yeager

12:28pm, May 8, 2017

Oxygen on comets might not date all the way back to the birth of the solar system.

Instead, interactions between water, particles streaming from the sun and grains of sand or rust on the comet’s surface could generate the gas. Those interactions could explain the surprising abundance of O2 detected in the fuzzy envelope of gas around comet 67P/Churyumov-Gerasimenko in 2015 (SN: 11/28/15, p. 6), researchers report May 8 in Nature Communications. Such reactions might also reveal how oxygen forms in other regions of space.

Molecular oxygen is very hard to find out there in the universe,” says Caltech chemical engineer Konstantinos Giapis. When the Rosetta spacecraft detected oxygen around comet 67P, astronomers argued it must be primordial, trapped in water ice as the comet formed roughly 4.6 billion years ago. Intrigued by the result, Giapis and Caltech colleague Yunxi Yao wanted to see if an alternative way to create O2 existed. Drawing on their work with fast-moving charged particles and materials such as silicon, they performed experiments that showed that charged water particles could slam into rust or sand grains and generate O2.

Something similar could happen on comet 67P, they suggest. As the sun evaporates water from the comet’s surface, ultraviolet light could strip an electron from the water, giving it a positive charge. Then, fast-moving particles in the solar wind could shoot the ionized water back toward the comet’s surface, where it could collide with rust or sand particles. Atoms of oxygen from the water could pair with atoms of oxygen from the rust or sand, creating O2.

The idea is plausible, says Paul Goldsmith, an astrophysicist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. He helped discover O2 in the Orion nebula and says the reaction might happen in places where young stars are forming and in other regions of space.

Rosetta mission scientist Kathrin Altwegg of the University of Bern in Switzerland calls the result interesting, but is skeptical it can explain comet 67P’s oxygen abundance. As the comet gets closer to the sun, a protective bubble develops around 67P, data from the mission showed; that bubble would prevent solar wind particles or other ionized particles from reaching the comet’s surface, Altwegg says. Also, the ratio of oxygen to un-ionized water also stays constant over time. It should be more variable if this chemical reaction were generating oxygen on the comet, she says.

Goldsmith, however, suggests researchers keep an open mind and design missions with instruments to test whether this newly detected reaction does, in fact, generate oxygen in space.

Planet Mars’ origins, new theory


This video from the USA says about itself:

The origin of Mars: How running water and extreme weather made the Red Planet

2 December 2016

Professor James Kasting joins RT America’s Ed Schultz to discuss new evidence suggesting that running water and extreme weather patterns played a crucial role in the formation of Mars.

From Science News:

Mars may not have been born alongside the other rocky planets

New origin story could explain mystery of Red Planet’s makeup

By Thomas Sumner

7:00am, May 5, 2017

Mars may have had a far-out birthplace.

Simulating the assembly of the solar system around 4.56 billion years ago, researchers propose that the Red Planet didn’t form in the inner solar system alongside the other terrestrial planets as previously thought. Mars instead may have formed around where the asteroid belt is now and migrated inward to its present-day orbit, the scientists report in the June 15 Earth and Planetary Science Letters. The proposal better explains why Mars has such a different chemical composition than Earth, says Stephen Mojzsis, a study coauthor and geologist at the University of Colorado Boulder.

The new work is an intuitive next step in a years-long rethink of the early solar system, says Kevin Walsh, a planetary scientist at the Southwest Research Institute in Boulder, Colo., who was not involved with the new simulation. “We only became comfortable within the last 10 years with the idea that planets move around, possibly a lot,” he says. “Planets may not have formed where we see them today.”

Mars, like Mercury, is a runt of the inner solar system, weighing in at only about a ninth of Earth’s mass. One of the reigning theories of planetary formation, the Grand Tack model, blames Jupiter for the Red Planet’s paltry size. In that scenario, the newly formed Jupiter migrated toward the sun until it reached Mars’ present-day orbit. A gravitational tug from Saturn then reversed Jupiter’s course, sending the gas giant back to the outer solar system (SN: 4/2/16, p. 7).

Gravitational effects of Jupiter’s sunward jaunt acted like a snowplow, scientists believe, causing a pileup of material near where Earth’s orbit is today. The bulk of that material formed Venus and Earth, and the scraps created Mercury and Mars. This explanation predicts that all the terrestrial planets formed largely from the same batch of ingredients (SN: 4/15/17, p. 18). But studies of Martian meteorites suggest that the Red Planet contains a different mix of various elements and isotopes, such as oxygen-17 and oxygen-18, compared with Earth.

Planetary scientist Ramon Brasser of the Tokyo Institute of Technology, Mojzsis and colleagues reran the Grand Tack simulations, keeping an eye on the materials that went into Mars’ creation to see if they could explain the different mix.

As with previous studies, the researchers found that the most probable way of creating a solar system with the same planet sizes and positions as seen today is to have Mars form within Earth’s orbit and migrate outward. However, this explanation failed to explain Mars’ strikingly different composition.

Another possible scenario, though seen in only about 2 percent of the team’s new simulations, is that Mars formed more than twice as far from the sun as its present-day orbit in the region currently inhabited by the asteroid belt. Then as Jupiter moved sunward, its gravitational pull yanked Mars into the inner solar system. Jupiter’s gravity also diverted planet-making material away from Mars, resulting in the planet’s relatively small mass. With Mars forming so far from the planetary feeding frenzy responsible for the other rocky planets, its composition would be distinct. While this scenario isn’t as likely as Mars forming in the inner solar system, it at least matches the reality of Mars’ makeup, Mojzsis says.

Such a distant origin means that the fledgling Mars would have received far less sunlight than originally thought, a challenge to early Mars’ possible habitability. Without a sustained thick atmosphere of heat-trapping greenhouse gases, the planet would have been too cold to sustain liquid water on its surface for long periods of time, Mojzsis argues. Though large meteorite impacts could have temporarily warmed Mars above freezing, the planet wouldn’t have had a consistently warm and wet youth similar to that of the early Earth, he says.

Confirming whether Mars really was born that far out in space will require taking a closer look at Venus’ mix of elements and isotopes, which the researchers predict would be similar to Earth’s. Venus’ composition is largely unknown because of a lack of Venusian meteorites found on Earth, and that mystery won’t be unlocked anytime soon: No missions to Venus are planned.