Monday, October 16, 2017

Spotting a KILONOVA: An Awesome Discovery in the Cosmos...

A kilonova (box) as seen by NASA's Hubble Space Telescope and Chandra X-ray Observatory in optical and infrared light, as well as in X-ray.
NASA / CXC / E. Troja

NASA Missions Catch First Light from a Gravitational-Wave Event (Press Release)

For the first time, NASA scientists have detected light tied to a gravitational-wave event, thanks to two merging neutron stars in the galaxy NGC 4993, located about 130 million light-years from Earth in the constellation Hydra.

Shortly after 8:41 a.m. EDT on Aug. 17, NASA's Fermi Gamma-ray Space Telescope picked up a pulse of high-energy light from a powerful explosion, which was immediately reported to astronomers around the globe as a short gamma-ray burst. The scientists at the National Science Foundation’s Laser Interferometer Gravitational-wave Observatory (LIGO) detected gravitational waves dubbed GW170817 from a pair of smashing stars tied to the gamma-ray burst, encouraging astronomers to look for the aftermath of the explosion. Shortly thereafter, the burst was detected as part of a follow-up analysis by ESA’s (European Space Agency’s) INTEGRAL satellite.

NASA's Swift, Hubble, Chandra and Spitzer missions, along with dozens of ground-based observatories, including the NASA-funded Pan-STARRS survey, later captured the fading glow of the blast's expanding debris.

"This is extremely exciting science," said Paul Hertz, director of NASA’s Astrophysics Division at the agency’s headquarters in Washington. "Now, for the first time, we've seen light and gravitational waves produced by the same event. The detection of a gravitational-wave source’s light has revealed details of the event that cannot be determined from gravitational waves alone. The multiplier effect of study with many observatories is incredible."

Neutron stars are the crushed, leftover cores of massive stars that previously exploded as supernovas long ago. The merging stars likely had masses between 10 and 60 percent greater than that of our Sun, but they were no wider than Washington, D.C. The pair whirled around each other hundreds of times a second, producing gravitational waves at the same frequency. As they drew closer and orbited faster, the stars eventually broke apart and merged, producing both a gamma-ray burst and a rarely seen flare-up called a "kilonova."

"This is the one we've all been waiting for," said David Reitze, executive director of the LIGO Laboratory at Caltech in Pasadena, California. "Neutron star mergers produce a wide variety of light because the objects form a maelstrom of hot debris when they collide. Merging black holes -- the types of events LIGO and its European counterpart, Virgo, have previously seen -- very likely consume any matter around them long before they crash, so we don't expect the same kind of light show."

"The favored explanation for short gamma-ray bursts is that they're caused by a jet of debris moving near the speed of light produced in the merger of neutron stars or a neutron star and a black hole," said Eric Burns, a member of Fermi's Gamma-ray Burst Monitor team at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "LIGO tells us there was a merger of compact objects, and Fermi tells us there was a short gamma-ray burst. Together, we know that what we observed was the merging of two neutron stars, dramatically confirming the relationship."

Within hours of the initial Fermi detection, LIGO and the Virgo detector at the European Gravitational Observatory near Pisa, Italy, greatly refined the event's position in the sky with additional analysis of gravitational wave data. Ground-based observatories then quickly located a new optical and infrared source -- the kilonova -- in NGC 4993.

To Fermi, this appeared to be a typical short gamma-ray burst, but it occurred less than one-tenth as far away as any other short burst with a known distance, making it among the faintest known. Astronomers are still trying to figure out why this burst is so odd, and how this event relates to the more luminous gamma-ray bursts seen at much greater distances.

NASA’s Swift, Hubble and Spitzer missions followed the evolution of the kilonova to better understand the composition of this slower-moving material, while Chandra searched for X-rays associated with the remains of the ultra-fast jet.

When Swift turned to the galaxy shortly after Fermi’s gamma-ray burst detection, it found a bright and quickly fading ultraviolet (UV) source.

"We did not expect a kilonova to produce bright UV emission," said Goddard’s S. Bradley Cenko, principal investigator for Swift. "We think this was produced by the short-lived disk of debris that powered the gamma-ray burst."

Over time, material hurled out by the jet slows and widens as it sweeps up and heats interstellar material, producing so-called afterglow emission that includes X-rays.

But the spacecraft saw no X-rays -- a surprise for an event that produced higher-energy gamma rays.

NASA’s Chandra X-ray Observatory clearly detected X-rays nine days after the source was discovered. Scientists think the delay was a result of our viewing angle, and it took time for the jet directed toward Earth to expand into our line of sight.

"The detection of X-rays demonstrates that neutron star mergers can form powerful jets streaming out at near light speed," said Goddard's Eleonora Troja, who led one of the Chandra teams and found the X-ray emission. "We had to wait for nine days to detect it because we viewed it from the side, unlike anything we had seen before."

On Aug. 22, NASA’s Hubble Space Telescope began imaging the kilonova and capturing its near-infrared spectrum, which revealed the motion and chemical composition of the expanding debris.

"The spectrum looked exactly like how theoretical physicists had predicted the outcome of the merger of two neutron stars would appear," said Andrew Levan at the University of Warwick in Coventry, England, who led one of the proposals for Hubble spectral observations. "It tied this object to the gravitational wave source beyond all reasonable doubt."

Astronomers think a kilonova's visible and infrared light primarily arises through heating from the decay of radioactive elements formed in the neutron-rich debris. Crashing neutron stars may be the universe's dominant source for many of the heaviest elements, including platinum and gold.

Because of its Earth-trailing orbit, Spitzer was uniquely situated to observe the kilonova long after the Sun moved too close to the galaxy for other telescopes to see it. Spitzer's Sept. 30 observation captured the longest-wavelength infrared light from the kilonova, which unveils the quantity of heavy elements forged.

"Spitzer was the last to join the party, but it will have the final word on how much gold was forged," says Mansi Kasliwal, Caltech assistant professor and principal investigator of the Spitzer observing program.

Numerous scientific papers describing and interpreting these observations have been published in Science, Nature, Physical Review Letters and The Astrophysical Journal.

Gravitational waves were directly detected for the first time in 2015 by LIGO, whose architects were awarded the 2017 Nobel Prize in physics for the discovery.


A kilonova (box), located within the galaxy NGC 4993, as seen by NASA's Hubble Space Telescope.

Tuesday, October 10, 2017

Wise Words By Kylo Ren (Or Rian Johnson)...

Kylo Ren wants to eliminate his past in STAR WARS: THE LAST JEDI.

"Let the past die. Kill it...if you have to. That's the only way to become who you're meant to be."

So are the words spoken by Kylo Ren (Adam Driver) in the newest trailer for this December's Star Wars: The Last Jedi. Overlooking the fact that the preview hints at the aspiring Sith Lord performing matricide (right after committing patricide in 2015's The Force Awakens), this quote applies to the real world as well. As the meme below also shows, sometimes we need to do drastic things to eliminate the past in order to focus on the future. I've been working on this since earlier this year—getting rid of things that I've had since my childhood to be able to look to the present and what lies ahead. I've been a little successful at this so far, hah. But yea, methinks I'm gonna have to try a bit harder in stop dwelling on events that have come and gone and realize that I can't reach my full potential until I concentrate on the here and now.

Oh, Star Wars...always featuring memorable quotes to help guide fans like me as we try to, in the words of Supreme Leader Snoke (and um, Emperor Palpatine before him), fulfill our destiny. Credit The Last Jedi director Rian Johnson for coming up with that noteworthy line at the beginning of this Blog entry. Happy Tuesday!

Let it go.

Friday, October 06, 2017

Farewell, AIM...

Farewell, AOL Instant Messenger.

Just read the sad news that after 20 years, AOL Instant Messenger (AIM) will be shut down permanently on December 15. Despite the fact that I haven't used this program in years, I'm bummed to see it go. As stated in this article, one of my fondest memories after obtaining access to the Internet for the first time was using AIM to talk to my high school friends while living at a dorm during my first year in college (Go Beach! That would be Cal State Long Beach). Not just my high school friends, but a couple of girls that I met on the Web as well! Yup, this was back when I was still social—Internet-wise, that is—and cared about having online conversations with my buddies instead of spending time nowadays reading a bunch of news pertaining to NASA, Star Wars and other movies, and how Donald Trump continues to prove that he's a moronic dotard day after day. But that's beside the point. Farewell AIM... Thanks for the online memories from over a decade ago. 1998 to 2005, to be exact.

My screenname on AIM was CoRollaPnOy and thugman77. Or was it thugman_77? Naw, it was thugman77. TGIF!

Tuesday, October 03, 2017

InSight Update: Send Your Name to the Red Planet!

An artist's concept of NASA's InSight lander on the surface of Mars.

Another Chance to Put Your Name on Mars (Press Release)

When it lands on Mars in November of 2018, NASA's InSight lander will be carrying several science instruments -- along with hundreds of thousands of names from members of the public.

In 2015, nearly 827,000 people signed up to add their names to a silicon microchip onboard the robotic spacecraft. NASA is now adding a second microchip, giving the public another chance to send their names to Mars.

New submissions will be accepted from Oct. 2 to Nov. 1, 2017, at the following link:

"Mars continues to excite space enthusiasts of all ages," said Bruce Banerdt, the InSight mission's principal investigator at NASA's Jet Propulsion Laboratory in Pasadena, California. "This opportunity lets them become a part of the spacecraft that will study the inside of the Red Planet."

This fly-your-name opportunity comes with "frequent flier" points reflecting an individual's personal participation in NASA's exploration of Mars. These points span multiple missions and multiple decades. Participants who sent their names on the previous InSight opportunity in 2015 can download a "boarding pass" and see their "frequent flier" miles.

As part of this frequent flier program, a chip carrying the names of 1.38 million people also flew aboard the first flight of NASA's Orion spacecraft in 2014. NASA is building Orion to carry astronauts to deep space destinations that will enable future missions to Mars.

After InSight, the next opportunity to earn frequent flier points will be NASA's Exploration Mission-1, the first flight bringing together the Space Launch System rocket and Orion spacecraft to travel thousands of miles beyond the Moon in preparation for human missions to Mars and beyond.

InSight will be the first mission to explore Mars' deep interior. The spacecraft will set down a seismometer to detect marsquakes and meteor strikes, using the seismic energy of these phenomena to study material far below the Martian surface. It also will deploy a self-hammering heat probe that will burrow deeper into the ground than any previous device on the Red Planet. These and other InSight investigations will improve our understanding about the formation and evolution of all rocky planets, including Earth.

InSight is scheduled to launch from Vandenberg Air Force Base, California, in May of 2018.

Source: NASA.Gov


Lockheed Martin engineers take the InSight Mars lander out of temporary storage in June of begin testing the spacecraft prior to its launch in May of 2018.
NASA / JPL - Caltech / Lockheed Martin

Monday, October 02, 2017

Tragedy in Las Vegas...

Police officers and regular citizens take cover behind a cop car after a gunman opened fire on a country music concert in Las Vegas...on October 1, 2017.

My heartfelt condolences to the families of the 50+ individuals who lost their lives yesterday...and to the 500+ other people who were injured in last night's horrific shooting outside the Mandalay Bay Resort and Casino in Las Vegas. The white domestic terrorist who committed this atrocious act took his own life before he could be apprehended and answer for his crimes—so may he rot in hell instead. The topic of gun control must once again be brought up, but if the meme below is any indication, the death of dozens of concertgoers last night won't prompt Republicans to grow a pair and stand up to the National Rifle Association by enacting tougher gun laws in our nation. 'Cause you know, as far as the GOP is concerned Americans need their guns but don't deserve to have universal healthcare. Yes, I'm politicizing this.

Another dark and disgraceful day for this country.

Police officers escort children to safety after the Sandy Hook Elementary School shooting on December 14, 2012.

Sunday, October 01, 2017

A Weird Dream to Save the World...

So last night, I had an odd but memorable dream where I was part of a ragtag team that had to save the world from...a giant chicken (much bigger than the one that Peter Griffin occasionally scraps with on FOX TV's Family Guy). The team consisted of ex-coworkers, random ladies that I may or may not have met in real life, Jayma Mays from the new film American Made (which I saw at the theater yesterday; great movie) and Sheldon Cooper from The Big Bang Theory. The last thing we did before I woke up (darn it) was dive into a giant underground chasm while riding inside large garbage bags. Again, this was a weird dream. That giant chicken still lurks since we weren't able to complete our adventure... Maybe I'll dream this journey again tonight!

Oh, and the beautiful and talented Milana Vayntrub was in another dream I had last night. No— Nothing creepy; we were on the same team for some math competition or something. Would've been cool if she helped us take on that chicken...fighting as none other than Squirrel Girl. Anyways, Happy October!