A new analysis of Apollo lunar rocks provides strong new evidence for the theory that the Moon was formed when the Earth was hit by a Mars’ sized planet.

A new analysis of Apollo lunar rocks provides strong new evidence for the theory that the Moon was formed when the Earth was hit by a Mars’ sized planet.

The abstract from this just released science paper summarizes the scientific problem.

Earth formed in a series of giant impacts, and the last one made the Moon. This idea, an edifice of post-Apollo science, can explain the Moon’s globally melted silicate composition, its lack of water and iron, and its anomalously large mass and angular momentum. But the theory is seriously called to question by increasingly detailed geochemical analysis of lunar rocks. Lunar samples should be easily distinguishable from Earth, because the Moon derives mostly from the impacting planet, in standard models of the theory. But lunar rocks are the same as Earth in O, Ti, Cr, W, K, and other species, to measurement precision. Some regard this as a repudiation of the theory; others say it wants a reformation. Ideas put forward to salvage or revise it are evaluated, alongside their relationships to past models and their implications for planet formation and Earth.

The new analysis has found that lunar rocks do differ from Earth in certain ways. Not surprisingly, however, the results have uncertainties.

The rupture of a drum at a nuclear waste site in New Mexico has shut down a neutrino experiment.

The rupture of a drum at a nuclear waste site in New Mexico has shut down a neutrino experiment.

This article, from Nature, focuses on the harm done to the science experiment, which is considerable and very unfortunate. However, scroll to the end of the article to learn a little about the drum rupture, which has serious implications for the storage of nuclear waste anywhere.

The predicted new meteor shower last night was less than hoped but intriguing nonetheless.

The predicted new meteor shower last night was less than hoped but intriguing nonetheless.

Based on a few reports via e-mail and my own vigil of two and a half hours centered on the predicted maximum of 2 a.m. CDT (7 UT) Saturday morning the Camelopardalid meteor shower did not bring down the house. BUT it did produce some unusually slow meteors and (from my site) one exceptional fireball with a train that lasted more than 20 minutes.

On the road

On Thursday and Friday I will likely not be able to do much posting, as I am heading up to Kitt Peak to watch an amateur astronomer do overnight observations using the 2.1 meter telescope on the mountain. I will also be taking a tour of the numerous facilities on the mountain top. All of this is in connection with an article I am writing for Sky & Telescope.

I am unsure if I will have internet service there. If I do, I will continue to post. Otherwise I will return Friday afternoon and pick up from there.

Update, Friday mid-day: I am back. Though I had access to the internet, I was too busy with other business to post. A lot of news stories since yesterday, so there will be a lot of posts in the next few hours.

NASA has approved a new mission for the crippled Kepler space telescope, allowing observations to continue for another two years.

Like a phoenix: NASA has officially approved the new mission for the crippled Kepler space telescope, allowing observations to continue for another two years.

During the K2 mission, Kepler will stare at target fields in the plane of Earth’s orbit, known as the ecliptic, during observing campaigns that last about 75 days each. In this orientation, solar radiation pressure can help balance the spacecraft, making the most of Kepler’s compromised pointing ability, team members said.

Hopefully the application of clever engineering will allow scientists to get data good enough to spot some more exoplanets.

Want to watch some astronomers blow up the top of a mountain? You can!

Want to watch some astronomers blow up the top of a mountain? You can!

Seriously, construction crews will in June begin blasting to prepare this mountain top in Chile for the European Extremely Large Telescope (E-ELT), a gigantic optical telescope that will have a primary mirror 39 meters or 128 feet across and is scheduled for completion sometime in the next decade. To mark the event they will be providing a live stream for everyone worldwide to watch.

Rosetta photographs its target comet as it comes to life.

Rosetta photographs its target comet as it comes to life.

The comet 67P/Churyumov-Gerasimenko, target of ESA’s Rosetta mission, has begun to develop a dust coma. This can be seen in a series of images taken by OSIRIS, the spacecraft’s scientific imaging system, between March 27th and May 4th. In the images from the end of April, the dust that the comet is already emitting is clearly visible as an evolving coma and reaches approximately 1300 kilometers into space.

Some scientists are now calling into question the BICEP2 results that confirmed the existence of inflation just after the Big Bang.

The uncertainty of science: Some scientists are now calling into question the BICEP2 results that confirmed the existence of inflation just after the Big Bang.

The biggest discovery in cosmology in a decade could turn out to be an experimental artifact—at least according to an Internet rumor. The team that reported the discovery is sticking by its work, however.

Eight weeks ago, researchers working with a specialized telescope at the South Pole reported the observation of pinwheel-like swirls in the polarization of the afterglow of the big bang, or cosmic microwave background (CMB). Those swirls are traces of gravitational waves rippling through the fabric of spacetime a sliver of a second after the big bang, argue researchers working with the Background Imaging of Cosmic Extragalactic Polarization 2 (BICEP2) telescope. Such waves fulfilled a prediction of a wild theory called inflation, which says that in the first 10-32 seconds, the universe underwent a mind-boggling exponential growth spurt. Many scientists hailed the result as a “smoking gun” for inflation.

However, scientists cautioned that the result would have to be scrutinized thoroughly. And now a potential problem with the BICEP analysis has emerged, says Adam Falkowski, a theoretical particle physicist at the Laboratory of Theoretical Physics of Orsay in France and author of the Résonaances blog. The BICEP researchers mapped the polarization of the CMB across a patch of sky measuring 15° by 60°. To study the CMB signal, however, they first had to subtract the “foreground” of microwaves generated by dust within our galaxy, and the BICEP team may have done that incorrectly, Falkowski reports on his blog today.

When the BICEP2 result was announced, the media went crazy over it. I however didn’t even post anything about it, as I know from experience that cosmological results such as this are very tentative and require confirmation. Too often, they turn out to be false results, with the scientists in charge fooled by the uncertain nature of their data.

The results from BICEP2 might still hold up. We need to wait a bit longer to find out.

It turns out that the object dubbed G2 that is zipping past the Milky Way’s central black hole is behaving not like a cloud but more like a star.

The uncertainty of science: It turns out that the object dubbed G2 that is zipping past the Milky Way’s central black hole is behaving not like a cloud but more like a star.

The latest observations by the Keck Observatory in Hawaii show that the gas cloud called “G2” was surprisingly still intact, even during its closest approach to the supermassive black hole at the center of our Milky Way galaxy. Astronomers from the UCLA Galactic Center Group reported today that observations obtained on March 19 and 20, 2014 show the object’s density was still “robust” enough to be detected. This means G2 is not just a gas cloud, but likely has a star inside.

When I wrote a piece about this object for Sky & Telescope I found that among astronomers there was great skepticism about it being just a gas cloud that would be ripped apart when it flew past the black hole. The early data was not conclusive, but enough of it suggested G2 was a star, not a cloud. It turns out here that the skeptics were right.

For the first time astronomers think they have measured the rotation rate of an exoplanet, thus determining the length of its day.

For the first time astronomers think they have measured the rotation rate of an exoplanet, thus determining the length of its day.

Ignas Snellen and his colleagues at Leiden University in the Netherlands report in Nature1 that a gaseous planet orbiting the star β Pictoris rotates at 25 kilometres per second at its equator — faster than any planet in the Solar System and about 50 times faster than Earth. A day on the planet, called β Pictoris b, lasts just over eight hours, even though the planet has a diameter more than 16 times that of Earth’s and carries more than 3,000 times Earth’s heft.

This result falls under my category of “the uncertainty of science.” Though quite cool, and based on real data, the uncertainties are great. Don’t bet the house that this result will stand up to closer observations in the future.

The existence of a Kepler-found earth-sized planet in the habitable zone has been confirmed.

Worlds without end: The existence of a Kepler-found earth-sized planet in the habitable zone has been confirmed.

The newfound planet, called Kepler-186f, was first spotted by NASA’s Kepler space telescope and circles a dim red dwarf star about 490 light-years from Earth. While the host star is dimmer than Earth’s sun and the planet is slightly bigger than Earth, the positioning of the alien world coupled with its size suggests that Kepler-186f could have water on its surface, scientists say.

In this new work, the Keck and Gemini ground-based telescopes confirmed Kepler’s discovery.

Scientists have found that Saturn’s hexagon-shaped jet stream is deeply rooted and that its rotation might be revealing the planet’s rotation as well.

Scientists have found that Saturn’s hexagon-shaped jet stream is deeply rooted and that its rotation might be revealing the planet’s rotation as well.

Due to the tilt of approximately 27º of the planet Saturn, its polar atmosphere undergoes intense seasonable variations with long polar nights lasting over seven years, followed by a long period of 23 years of variable illumination. However, the seasonal variations do not affect the hexagon and its jet stream at all, so both are part of an extensive wave, deeply rooted in Saturn’s atmosphere. The UPV/EHU researchers suggest that the hexagon and its stream are the manifestation of a “Rossby wave” similar to those that form in the mid-latitudes of the earth. On our planet the jet stream meanders from west to east and brings, associated with it, the system of areas of low pressure and anticyclones which we have been seeing regularly on weather maps.

On Saturn, a hydrogen gas planet, ten times the size of the Earth, cold in its upper clouds, without a solid surface, and with an atmosphere as deep as that of an ocean, “the hexagonal wavy motion of the jet stream is expected to be propagated vertically and reveal to us aspects of the planet’s hidden atmosphere,” pointed out Agustín Sánchez-Lavega, Head of the Planetary Sciences research group. “The movement of the hexagon could therefore be linked to the depths of Saturn, and the rotation period of this structure, which, as we have been able to ascertain, is 10 hours, 39 minutes and 23 seconds, could be that of the planet itself,” he added. Saturn is the only planet in the Solar System whose rotation period is not yet known.

The oldest galaxy known might be a tiny dwarf galaxy orbiting the Milky Way.

The oldest galaxy known might be a tiny dwarf galaxy orbiting the Milky Way.

Segue 1 is very, very tiny. It appears to contain only a few hundred stars, compared with the few hundred billion stars in the Milky Way Galaxy. Researchers led by Anna Frebel of the Massachusetts Institute of Technology in Cambridge collected detailed information on the elemental composition of six of the brightest of Segue 1’s stars using the Las Campanas Observatory’s Magellan Telescopes in Chile and the Keck Observatory in Hawaii. The measurements, reported in a paper accepted for Astrophysical Journal and posted on the arXiv repository, revealed that these stars are made almost entirely of hydrogen and helium, and contain just trace amounts of heavier elements such as iron. No other galaxy studied holds so few heavy elements, making Segue 1 the “least chemically evolved galaxy known.”

Complex elements are forged inside the cores of stars by the nuclear fusion of more basic elements such as hydrogen and helium atoms. When stars explode in supernovae, even heavier atoms are created. elements spew into space to infuse the gas that births the next generation of stars, so that each successive generation contains more and more heavy elements, known as metals. “Segue 1 is so ridiculously metal-poor that we suspect at least a couple of the stars are direct descendants of the first stars ever to blow up in the universe,” says study co-author Evan Kirby of the University of California, Irvine.

Because of a $10 million shortfall in its astrophysics budget, NASA is weighing the fate of nine operating space telescopes.

Because of a $10 million shortfall in its astrophysics budget, NASA is weighing the fate of nine operating space telescopes.

Six of the projects vying for extended funding are U.S.-based. Three are overseen by international space agencies and have U.S. partners.

The NASA missions are: the Fermi Gamma-ray Space Telescope; the Nuclear Spectroscopic Telescope Array X-ray observatory; the infrared Spitzer Space Telescope; the Swift Telescope, which tracks gamma-ray bursts; a proposed Kepler space telescope follow-on mission known as K2; and the Wide-field Infrared Survey Explorer, which was brought out of hibernation last year to help search for asteroids on a collision course with Earth.

Also in the running are two European Space Agency missions, XMM-Newton — an X-ray observatory — and Planck, which studied relic radiation from the Big Bang. Planck was decommissioned in October, but its data analysis program continues.

The final contender is Japan’s Suzaku X-ray telescope.

Astronomers have found an asteroid with its own rings.

Astronomers have found an asteroid with its own rings.

Chariklo is the largest member of a class known as the Centaurs and it orbits between Saturn and Uranus in the outer Solar System. Predictions had shown that it would pass in front of the star UCAC4 248-108672 on 3 June 2013, as seen from South America. Astronomers using telescopes at seven different locations, including the 1.54-metre Danish and TRAPPIST telescopes at ESO’s La Silla Observatory in Chile, were able to watch the star apparently vanish for a few seconds as its light was blocked by Chariklo — an occultation.

But they found much more than they were expecting. A few seconds before, and again a few seconds after the main occultation there were two further very short dips in the star’s apparent brightness. Something around Chariklo was blocking the light! By comparing what was seen from different sites the team could reconstruct not only the shape and size of the object itself but also the shape, width, orientation and other properties of the newly discovered rings.

The team found that the ring system consists of two sharply confined rings only seven and three kilometres wide, separated by a clear gap of nine kilometres — around a small 250-kilometre diameter object orbiting beyond Saturn.

Astronomers have discovered a new dwarf planet about 300 miles wide at the very edge of the solar system.

Astronomers have discovered a new dwarf planet about 300 miles wide at the outer edge of the solar system.

The closest it gets to the Sun is 80 AU, or about 7.4 billion miles. More tantalizing, however,

… the findings also suggest the presence of another large planet in the outer reaches of the solar system. When the authors plotted the motion of Sedna, 2012 VP113, and distant Kuiper belt objects, they noticed some odd behaviors which they couldn’t explain — but which a massive, “super-Earth” planet about 250 AU away could. They note that such a dimly lit planet “would be fainter than current all-sky survey detection limits, as would larger and more distant perturbers” (i.e., planets), so it’s certainly possible… but right now it’s little more than a guess. A weird, intriguing guess.

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