10 Billion Year-old Neutrino Found

Way to go Fermi!

Nearly 10 billion years ago, the black hole at the center of a galaxy known as PKS B1424-418 produced a powerful outburst. Light from this blast began arriving at Earth in 2012. Now astronomers using data from NASA’s Fermi Gamma-ray Space Telescope and other space- and ground-based observatories have shown that a record-breaking neutrino seen around the same time likely was born in the same event. — NASA

Video

Using Galaxies as Dark Energy Tools

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Using galaxy clusters to study dark energy – very innovative!

From NASA:

These four galaxy clusters were part of a large survey of over 300 clusters used to investigate dark energy, the mysterious energy that is currently driving the accelerating expansion of the Universe. In these composite images, X-rays from NASA’s Chandra X-ray Observatory (purple) have been combined with optical light from the Hubble Space Telescope and Sloan Digital Sky Survey (red, green, and blue).

Researchers used a novel technique that takes advantage of the observation that the outer reaches of galaxy clusters, the largest structures in the universe held together by gravity, show similarity in their X-ray emission profiles and sizes. That is, more massive clusters are simply scaled up versions of less massive ones, similar to Russian dolls that nest inside one another.

The amount of matter in the Universe, which is dominated by the unseen substance called dark matter, and the properties of dark energy (what astronomers call cosmological parameters) affect the rate of expansion of the Universe and, therefore, how the distances to objects changes with time. If the cosmological parameters used are incorrect and a cluster is inferred to be traveling away faster than the correct value, then a cluster will appear to be larger and fainter due to this “Russian doll” property. If the cluster is inferred to be traveling away more slowly than the correct value, the cluster will be smaller and brighter than a cluster according to theory.

These latest results confirm earlier studies that the amount of dark energy has not changed over billions of years. They also support the idea that dark energy is best explained by the “cosmological constant,” which Einstein first proposed and is equivalent to the energy of empty space.

The galaxy clusters in this large sample ranged in distance from about 760 million to 8.7 billion light years from Earth, providing astronomers with information about the era where dark energy caused the once-decelerating expansion of the Universe to accelerate.

The X-ray emission in the outer parts of galaxy clusters is faint because the gas is diffuse there. To deal with this issue in this study, the X-ray signal from different clusters was added together. Regions near the centers of the clusters are excluded from the analysis because of large differences between the properties of different clusters caused by supermassive black hole outbursts, the cooling of gas and the formation of stars.

A paper describing these results by Andrea Morandi and Ming Sun (University of Alabama at Huntsville) appeared in the April 11th, 2016 issue of the Monthly Notices of the Royal Astronomical Society journal and is available online. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra’s science and flight operations.

Image credits: X-ray: NASA/CXC/Univ. of Alabama/A. Morandi et al; Optical: SDSS, NASA/STScI

Curious Wheels Update

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A few days ago I did a short post on the status of Curiosity’s wheels and yesterday the mission team released their assessment:

The team operating NASA’s Curiosity Mars rover uses the Mars Hand Lens Imager (MAHLI) camera on the rover’s arm to check the condition of the wheels at routine intervals. This image of Curiosity’s left-middle and left-rear wheels is part of an inspection set taken on April 18, 2016, during the 1,315th Martian day, or sol, of the rover’s work on Mars.

Holes and tears in the wheels worsened significantly during 2013 as Curiosity was crossing terrain studded with sharp rocks on its route from near its 2012 landing site to the base of Mount Sharp. Team members are keeping a close eye for when any of the zig-zag shaped treads, call grousers, begin to break. Longevity testing with identical wheels on Earth indicates that when three grousers on a given wheel have broken, that wheel has reached about 60 percent of its useful mileage. Since Curiosity’s current odometry of 7.9 miles (12.7 kilometers) is about 60 percent of the amount needed for reaching all the geological layers planned in advance as the mission’s science destinations, and no grousers have yet broken, the accumulating damage to wheels is not expected to prevent the rover from reaching those destinations on Mount Sharp.

As with other images from Curiosity’s cameras, all of the wheel-inspection exposures are available in the raw images collections at http://mars.nasa.gov/msl/multimedia/raw/. The Sol 1315 MAHLI raw images are at http://mars.nasa.gov/msl/multimedia/raw/?s=1315&camera=MAHLI. The rover’s location during this wheel check was on “Naukluft Plateau” on lower Mount Sharp.

Curiosity’s six aluminum wheels are about 20 inches (50 centimeters) in diameter and 16 inches (40 centimeters) wide. Each of the six wheels has its own drive motor, and the four corner wheels also have steering motors.

Image Credit: NASA/JPL-Caltech/MSSS

Hubble Finds A Moon

Peering to the outskirts of our solar system, NASA’s Hubble Space Telescope has spotted a small, dark moon orbiting Makemake, the second brightest icy dwarf planet — after Pluto — in the Kuiper Belt.

The moon — provisionally designated S/2015 (136472) 1 and nicknamed MK 2 — is more than 1,300 times fainter than Makemake. MK 2 was seen approximately 13,000 miles from the dwarf planet, and its diameter is estimated to be 100 miles across. Makemake is 870 miles wide. The dwarf planet, discovered in 2005, is named for a creation deity of the Rapa Nui people of Easter Island. NASA

Discovered by: Michael E. Brown, Chad Trujillo, and David Rabinowitz on 31 March 2005, MakeMake was at opposition in March and the magnitude was around 16.1.  Probably about as bright as it gets. To get an idea of magnitudes have a look at this page from the International Comet Quarterly.

Real Ring Art and More

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This Cassini image gives us a unique almost chaotic view of Saturn’s rings that look something like modern art. How does it work? The image was taken 14 degrees above the ring plane and we see the rings and their shadows on the planet.

The other thing we can see is the tiny moon Pan. Look in the narrow ring gap (known as the Encke Gap) about in the center of the image (click to enlarge it). Pan is just 28 km / 17 miles across.

Image: NASA/JPL-Caltech/Space Science Institute

and MORE:

Hubble’s Bubble

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The Bubble Nebula is a great imaging target, very difficult (IMHO) to get just just right. I’ve yet to do it. This is an incredible image from Hubble is a composite of separate exposures acquired by the WFC3/UVIS instrument.

For the 26th anniversary of Hubble’s launch on April 24, 1990, the telescope has photographed an enormous, balloon-like bubble being blown into space by a super-hot, massive star. Astronomers trained the iconic telescope on this colorful feature, called the Bubble Nebula, or NGC 7635. The bubble is 7 light-years across — about one-and-a-half times the distance from our sun to its nearest stellar neighbor, Alpha Centauri. The Bubble Nebula lies 7,100 light-years from Earth in the constellation Cassiopeia. – Hubblesite

Image: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

Sentinel 1B Launch

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If you happened by yesterday to watch the launch of Sentinel 1B you know it was postponed due to weather issues.

The good part about the delay is I will get to see the launch if it goes as planned today.

ESA was kind enough to indicate the launch times in a variety of time zones:

Delayed again.  These times are listed on the ESA site, but may not be current  (they don’t seem to be ).

  • 06:02:13 p.m., (Local time in French Guiana)
  • 05:02:13 p.m., (in Washington, D.C.)
  • 09:02:13 p.m., (UTC)
  • 11:02:13 p.m., (in Paris)
  • 00:02:13 a.m., (in Moscow) on April

Here is the link for the live coverage from ESA.

The image (copyright ESA–Manuel Pedoussaut, 2016) shows the Soyuz VS14 upper composite hoisted to the top of the service tower in preparation for launch.

Ready for Launch

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The Sentinel-1B is shown here being placed in a fairing in preparation for launch tomorrow 22 April 2016.

Sentinel-1B will join Sentinel-1 providing radar images of Earth for Europe’s Copernicus environmental monitoring program.

Launch Date: 22 April 2016
Launch Location: French Guiana
Launch Time: 21:02 GMT / 23:02 CEST / 17:02 EDT
Live Coverage: YES via ESA – coverage starts at: 20:10 GMT / 22:10 CEST / 16:10 EDT.