Well, That's A Relief

Observations made in March enabled astronomers to determine that the asteroid Apophis, which had been given a 2.7% chance of hitting the Earth on April 13, 2029 (Friday, of course), will in fact miss us.

Apophis is a stony asteroid about 1,100 feet across, weighing around 60 million tons. If it struck the Earth it would release the equivalent of 1,200 megatons of TNT -- that's 75,000 Hiroshima bombs, or 24 of the biggest nuclear weapon ever exploded, Tsar Bomba. It would, I'm guessing, make for a really bad year, and a pretty bad next five years or so, but wouldn't be a civilization-killer. By contrast, the Chicxulub impact, which wiped out the dinosaurs and 75% of everybody else, is rated at one hundred million megatons.

It won't miss by much, though -- about 20,000 miles. Which, in astronomical terms, is about one-fifth of a cat's whisker. In fact, we have hundreds of active satellites (those blue dots in the video above) in geosynchronous orbit, which is 22,500 miles out. I want to know what the chances are that Apophis will perturb some of their orbits and make them useless, or even hit one. That would be fun to watch.

"We have seen what we thought was unseeable"

"The first picture of a black hole opens a new era of astrophysics."

This is what a black hole looks like.

A world-spanning network of telescopes called the Event Horizon Telescope zoomed in on the supermassive monster in the galaxy M87 to create this first-ever picture of a black hole.

“We have seen what we thought was unseeable. We have seen and taken a picture of a black hole,” Sheperd Doeleman, EHT Director and astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., said April 10 in Washington, D.C., at one of seven concurrent news conferences. The results were also published in six papers in the Astrophysical Journal Letters.

“We’ve been studying black holes so long, sometimes it’s easy to forget that none of us have actually seen one,” France Córdova, director of the National Science Foundation, said in the Washington, D.C., news conference. Seeing one “is a Herculean task,” she said. (More at this Link)

"Can we take a moment to thank Jupiter"

"The planet is so vast that it's gravity helps to pull and interrupt most potential asteroids from hitting Earth."

https://imgur.com/gallery/4YT01

Europa photographed in front of the Great Red Spot on Jupiter

click Link to expand

The Universe in 4 Minutes

Link to video

Every orbiter, lander, rover, flyby, and impactor that completed its mission

Click Link to enlarge

Phoenix Aurora Over Iceland

Link to source

Link has a description and shows the constellations when hovering over the picture.

Planetary Photography

Venus / Earth / Moon / Mars / Titan pic.twitter.com/FkYXDcQxBP

— Life on Earth (@planetepics) June 5, 2015

"Kepler Mission Discovers a World Orbiting Two Stars"

"The existence of a world with a double sunset, as portrayed in the film Star Wars more than 30 years ago, is now scientific fact. NASA's Kepler mission has made the first unambiguous detection of a circumbinary planet - a planet orbiting two stars - 200 light-years from Earth."

"This discovery confirms a new class of planetary systems that could harbor life," Kepler principal investigator William Borucki said. "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."

“The warped side of the universe”

"How Building a Black Hole for Interstellar Led to an Amazing Scientific Discovery"

We are about to land on a smelly comet

“What’s surprising is we already have extremely rich chemistry at this distance from the sun,”

“The perfume of 67P/C-G is quite strong, with the odor of rotten eggs (hydrogen sulfide), horse stable (ammonia), and the pungent, suffocating odor of formaldehyde. This is mixed with the faint, bitter, almond-like aroma of hydrogen cyanide,” Kathrin Altwegg, head of the ROSINA project at the Center for Space and Habitability (CSH) at the University of Bern, described the smell. “Add some whiff of alcohol (methanol) to this mixture, paired with the vinegar-like aroma of sulfur dioxide and a hint of the sweet aromatic scent of carbon disulfide, and you arrive at the ‘perfume’ of our comet”.

The Smallest Star in the Universe... maybe

Video: Pulsar's Dramatic Morph Caught by Space Telescope

The Telegraph: Where Has All The Light In The Universe Gone?

“It’s as if you’re in a big, brightly-lit room, but you look around and see only a few 40-watt light bulbs,” noted Carnegie’s Juna Kollmeier, lead author of the study. “Where is all that light coming from? It’s missing from our census.”

“Either our accounting of the light from galaxies and quasars is very far off, or there’s some other major source of ionizing photons that we’ve never recognized,” Kollmeier said.

“We are calling this missing light the photon underproduction crisis. But it’s the astronomers who are in crisis -- somehow or other, the universe is getting along just fine.” (read the whole thing)

Cut and Paste: Results May Vary

"From our perspective on our spinning world, Mars rises in the east just as the sun sets in the west," NASA reports. "Then, after staying up in the sky the entire night, Mars sets in the west just as the sun rises in the east."

At the moment, NASA isn't ready to send human explorers to Mars, let alone out of the solar system. But some private organizations, including the federally funded 100 Year Starship project, plan to make manned interstellar travel possible within the next century, hoping that a huge increase in propulsion speed could reduce the travel time between stars to just a few hundred years. Icarus Interstellar, one of the groups involved in 100 Year Starship, asked Smith to make this calculation of how many passengers would be needed to keep that population healthy. The results are published in the April–May issue of Acta Astronomica.

At their closest point next week, Mars and Earth will "only" be about 57 million miles apart. Another treat awaits April 14, when the full moon also will appear near Mars.

"I did this study to materially help in putting together the millions of puzzle pieces that will be required to allow humanity to spread out from our earthly cradle," he says.

Paragraphs pulled from USA Today and from Popular Mechanics articles.

"Brightest Explosion In the Universe Ever Seen Defies Astronomy Theories"

"The really cool thing about this GRB (gamma-ray burst) is that because the exploding matter was traveling at [nearly] the speed of light, we were able to observe relativistic shocks," study co-author Giacomo Vianello, a postdoctoral scholar at Stanford University in California, said in a statement. "We cannot make a relativistic shock in the lab, so we really don't know what happens in it, and this is one of the main unknown assumptions in the model. These observations challenge the models and can lead us to a better understanding of physics."

Live Science beta

"There are likely billions of Earth-like planets in our Milky Way galaxy, astronomers say"

There are likely "tens of billions" of Earth-like planets in our Milky Way galaxy, according to a study released Monday by astronomers from the University of California-Berkeley and the University of Hawaii.

"Planets like our Earth are relatively common throughout the Milky Way galaxy," said astronomer Andrew Howard of the University of Hawaii.

In fact, the nearest Earth-like planet may be "only" 12 light years away, which is roughly 72 trillion miles.

Overall, astronomers now estimate that about one in five sun-like stars have planets that are nearly the size of Earth and also have a surface temperature conducive to the development of life.

USA Today, Doyle Rice