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Photo: FU Orionis resides near the imaginary shoulder of the great hunter constellation of Orion, at a location of about 3 degrees NW of Betelgeuse, Here: The constellation of Orion, as it can be seen by the naked eye. Lines have been drawn.
These planets are the first four from the sun: Mercury, Venus, Earth and Mars. They’re mostly made of rock and iron – whose particles don’t readily stick together. They could have been sticky enough if they had a coating of snow and organic goo, Hubbard says. But despite all Earth’s oceans and carbon-based life, our planet has too little water or carbon to support this explanation. Now Hubbard has suggested an intriguing solution to Earth’s difficult birth. In 1936, an infant star began to brighten, eventually shining over 100 times more brightly than it did originally. Now named FU Orionis, this star has stayed bright ever since. And several other stellar youngsters have done the same thing.
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BLINDED BY BEAUTY
How each culture views the Universe is guided by its beliefs in, for example, mathematical beauty or the structure of reality. If these ideas are deeply rooted, people tend to interpret all data as supportive of them — adding parameters or performing mathematical gymnastics to force the fit. Recall how the belief that the Sun moves around Earth led to the mathematically beautiful (and incorrect) theory of epicycles advocated by the ancient Greek philosopher Ptolemy. Similarly, modern cosmology is augmented by unsubstantiated, mathematically sophisticated ideas — of the multiverse, anthropic reasoning and string theory. The multiverse idea postulates the existence of numerous other regions of space-time, to which we have no access and in which the cosmological parameters have different values. The anthropic argument is then often applied. It holds that our own region has the parameters it does (including those of dark energy and dark matter) because other, more likely values would not have allowed life to develop near a star like the Sun in a galaxy such as the Milky Way. An overlooked problem with this argument is that, accord¬ing to one analysis, life is 1,000 times more likely to exist 10 trillion years from now around stars that weigh one-tenth the mass of the Sun. This means that terrestrial life might be premature and not the most likely form of life, even in our own Universe. A vibrant scientific culture encourages many interpretations of evidence, argues Avi Loeb. Abraham Loeb Frank B. Baird Jr. Professor of Science, Harvard University Chair, Harvard Astronomy Department Director, Institute for Theory and Computation (ITC) Founding Director, Black Hole Initiative (BHI) Chair, Breakthrough Starshot Advisory Committee Vice Chair, Board on Physics and Astronomy, National Academies 
Photo: No known restrictions on publication.2015.This planetary nebula is called PK 329-02.2 and is located in the constellation of Norma in the southern sky. It is also sometimes referred to as Menzel 2, or Mz 2, named after the astronomer Donald Menzel who discovered the nebula in 1922. When stars that are around the mass of the Sun reach their final stages of life, they shed their outer layers into space, which appear as glowing clouds of gas called planetary nebulae. The ejection of mass in stellar burnout is irregular and not symmetrical, so that planetary nebulae can have very complex shapes. In the case of Menzel 2 the nebula forms a winding blue cloud that perfectly aligns with two stars at its centre. In 1999 astronomers discovered that the star at the upper right is in fact the central star of the nebula, and the star to the lower left is probably a true physical companion of the central star. For tens of thousands of years the stellar core will be cocooned in spectacular clouds of gas and then, over a period of a few thousand years, the gas will fade away into the depths of the Universe. The curving structure of Menzel 2 resembles a last goodbye before the star reaches its final stage of retirement as a white dwarf. A version of this image was entered into the Hubble's Hidden Treasures image processing competition by contestant Serge Meunier. "...Now, for the first time, researchers have seen this scenario unfold. Andrew Vanderburg, an astronomer at the Harvard-Smithsonian Center for Astrophysics, was analyzing data from Kepler, which detects planets when they block the light of their sun. "One of the white dwarfs suddenly popped up with this really intriguing signature," Vanderburg says. As his team reports online today in Nature, the white dwarf, located in the constellation Virgo and named WD 1145+017, has at least one, and probably several, asteroids that are disintegrating. As a debris cloud from each asteroid passes between us and the star, Kepler detects a dimming of the star's light. "It's fascinating," says astronomer Michael Jura of the University of California, Los Angeles, who was not part of the discovery team. "They've actually caught in the act the process of some asteroid breaking into pieces, being disrupted by the white dwarf host star." Indeed, the star itself is the asteroids' enemy. Its gravity has torn them asunder, and its light is vaporizing their rock. The asteroids are so close to the star that they revolve in just 4.5 to 4.9 hours; Vanderburg estimates they are roughly the size of Ceres, the largest asteroid between the orbits of Mars and Jupiter...."
The presence of significant amounts of water ice in its composition[81] and evidence of recent geological resurfacing, raises the possibility that Ceres has a layer of liquid water in its interior.[22][127] This hypothetical layer is often called an ocean.[14] If such a layer of liquid water exists, it is hypothesized to be located between the rocky core and ice mantle like that of the theorized ocean on Europa.[22] The existence of an ocean is more likely if solutes (i.e. salts), ammonia, sulfuric acid or other antifreeze compounds are dissolved in the water.
LISA Pathfinder, formerly Small Missions for Advanced Research in Technology-2 (SMART-2), was an ESA spacecraft that was launched on 3 December 2015 on board Vega flight VV06.[3][4][5] The mission tested technologies needed for the Laser Interferometer Space Antenna (LISA), an ESA gravitational wave observatory planned to be launched in 2034. The scientific phase started on 8 March 2016 and lasted almost sixteen months.[6] In April 2016 ESA announced that LISA Pathfinder demonstrated that the LISA mission is feasible.
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