optic ray

When Dead Stars Collide!

Gravity has been making waves - literally.  Earlier this month, the Nobel Prize in Physics was awarded for the first direct detection of gravitational waves two years ago. But astronomers just announced another huge advance in the field of gravitational waves - for the first time, we’ve observed light and gravitational waves from the same source.

There was a pair of orbiting neutron stars in a galaxy (called NGC 4993). Neutron stars are the crushed leftover cores of massive stars (stars more than 8 times the mass of our sun) that long ago exploded as supernovas. There are many such pairs of binaries in this galaxy, and in all the galaxies we can see, but something special was about to happen to this particular pair.

Each time these neutron stars orbited, they would lose a teeny bit of gravitational energy to gravitational waves. Gravitational waves are disturbances in space-time - the very fabric of the universe - that travel at the speed of light. The waves are emitted by any mass that is changing speed or direction, like this pair of orbiting neutron stars. However, the gravitational waves are very faint unless the neutron stars are very close and orbiting around each other very fast.

As luck would have it, the teeny energy loss caused the two neutron stars to get a teeny bit closer to each other and orbit a teeny bit faster.  After hundreds of millions of years, all those teeny bits added up, and the neutron stars were *very* close. So close that … BOOM! … they collided. And we witnessed it on Earth on August 17, 2017.  

Credit: National Science Foundation/LIGO/Sonoma State University/A. Simonnet

A couple of very cool things happened in that collision - and we expect they happen in all such neutron star collisions. Just before the neutron stars collided, the gravitational waves were strong enough and at just the right frequency that the National Science Foundation (NSF)’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and European Gravitational Observatory’s Virgo could detect them. Just after the collision, those waves quickly faded out because there are no longer two things orbiting around each other!

LIGO is a ground-based detector waiting for gravitational waves to pass through its facilities on Earth. When it is active, it can detect them from almost anywhere in space.

The other thing that happened was what we call a gamma-ray burst. When they get very close, the neutron stars break apart and create a spectacular, but short, explosion. For a couple of seconds, our Fermi Gamma-ray Telescope saw gamma-rays from that explosion. Fermi’s Gamma-ray Burst Monitor is one of our eyes on the sky, looking out for such bursts of gamma-rays that scientists want to catch as soon as they’re happening.

And those gamma-rays came just 1.7 seconds after the gravitational wave signal. The galaxy this occurred in is 130 million light-years away, so the light and gravitational waves were traveling for 130 million years before we detected them.

After that initial burst of gamma-rays, the debris from the explosion continued to glow, fading as it expanded outward. Our Swift, HubbleChandra and Spitzer telescopes, along with a number of ground-based observers, were poised to look at this afterglow from the explosion in ultraviolet, optical, X-ray and infrared light. Such coordination between satellites is something that we’ve been doing with our international partners for decades, so we catch events like this one as quickly as possible and in as many wavelengths as possible.

Astronomers have thought that neutron star mergers were the cause of one type of gamma-ray burst - a short gamma-ray burst, like the one they observed on August 17. It wasn’t until we could combine the data from our satellites with the information from LIGO/Virgo that we could confirm this directly.

This event begins a new chapter in astronomy. For centuries, light was the only way we could learn about our universe. Now, we’ve opened up a whole new window into the study of neutron stars and black holes. This means we can see things we could not detect before.

The first LIGO detection was of a pair of merging black holes. Mergers like that may be happening as often as once a month across the universe, but they do not produce much light because there’s little to nothing left around the black hole to emit light. In that case, gravitational waves were the only way to detect the merger.

Image Credit: LIGO/Caltech/MIT/Sonoma State (Aurore Simonnet)

The neutron star merger, though, has plenty of material to emit light. By combining different kinds of light with gravitational waves, we are learning how matter behaves in the most extreme environments. We are learning more about how the gravitational wave information fits with what we already know from light - and in the process we’re solving some long-standing mysteries!

Want to know more? Get more information HERE.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com


Newest LIGO Signal Raises A Huge Question: Do Merging Black Holes Emit Light?

“The second merger held no such hints of electromagnetic signals, but that was less surprising: the black holes were of significantly lower mass, so any signal arising from them would be expected to be correspondingly lower in magnitude. But the third merger was large in mass again, more comparable to the first than the second. While Fermi has made no announcement, and Integral again reports a non-detection, there are two pieces of evidence that suggest there may have been an electromagnetic counterpart after all. The AGILE satellite from the Italian Space Agency detected a weak, short-lived event that occurred just half a second before the LIGO merger, while X-ray, radio and optical observations combined to identify a strange afterglow less than 24 hours after the merger.”

Whenever there’s a catastrophic, cataclysmic event in space, there’s almost always a tremendous release of energy that accompanies it. A supernova emits light; a neutron star merger emits gamma rays; a quasar emits radio waves; merging black holes emit gravitational waves. But if there’s any sort of matter present outside the event horizons of these black holes, they have the potential to emit electromagnetic radiation, or light signals, too. Our best models and simulations don’t predict much, but sometimes the Universe surprises us! With the third LIGO merger, there were two independent teams that claimed an electromagnetic counterpart within 24 hours of the gravitational wave signal. One was an afterglow in gamma rays and the optical, occurring about 19 hours after-the-fact, while the other was an X-ray burst occurring just half a second before the merger.

Could either of these be connected to these merging black holes? Or are we just grasping at straws here? We need more, better data to know for sure, but here’s what we’ve got so far!


Soft Glowing Raywood Stimboard

A special thanks to the wonderful @kittycole for letting me use her art! (I secretly adore Raywood and most Ryan ships in general. And I mean come on, Ray looks too cute in this.)

Credit Links:

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keep you warm — liam dunbar

summary ; in which y/n is sick and in need of liam dunbar’s cuddles. [191017]

warnings ; none

word count ; 1.6k


YOU FOUND YOURSELF awake still, into the late depths of the night. You sniffled lightly, and wrapped one of the many blankets crowding your bed tighter around your shivering body. With a harsh pounding against your skull, a sore throat, and despite the high temperatures gracing the summer season and the warmth spreading across your skin, a series of cold shivers - you were once again reminded of the sickness that had burdened your day (and now night too, apparently).

It took no genius to figure out you’d gotten incredibly sick. It also took no genius to figure out that you probably looked as rough as you felt. But that didn’t stop you from opening the cocoon of covers for your hand to slip out and blindly reaching for your phone on your bedside table through the inky shadows of the night, a grouchy groan slipping from your lips as you grasped the expensive object between your fingers and swiped to unlock.

You didn’t make an attempt to contain the string of croaky, expletive syllables that sounded with a painful sting under your breath as the glaring screen illuminated the dark room and brought burning tears to your squinting eyes, your mood decreasing more and more into the depths of brooding and dispiritedness as the minutes ticked further into the warm night.

Mildly unconscious of your actions, your thumbs pressed against your boyfriend’s name in your contacts and brought the phone up to the shell of your ear - listening to the repetitive dial tone with the ghost of a weak smile on your chapped lips, waiting patiently until the opposing side picked up. A few moments later, he did, and a muffled ruffling was heard as you softly called out his name,  “Li?”

“(Y/N)?” The comfort of Liam’s voice travelled through the speaker and reached your ears in hushed whispers. Without realising it, the press of a crestfallen weight, that had pushed harshly against your chest prior, lifted, and you already found yourself feeling slightly better.

Your head tilted to the side, your weary eyes peering over the clocked perched on the bedside cabinet, identifying the hands on the face to read half one in morning. With that acknowledgement, a burst of guilt swept through your fatigued being, “O-Oh, shit, Liam - I’m sorry, I didn’t realise it was so late-”

“Hey, hey,” He interrupted softly, and your rushed words fell to a faded silence, “What’s going on, baby? You sound sick - are you sick?”

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i could never lie to you // peter parker

summary ; a series of imagines (can be read individually too) that correlate with my headcanon of ‘dating peter parker would include’. also known as: 26 different ways to say ‘i love you’.

 in which peter is utterty ecstatic with y/n’s reaction to his sudden powers, and can’t help but fall for her even more because of it.

pairing ; peter parker & fem!reader

warnings ; none, just y/n and peter being dorks

word count ; 1.6k

published ; 13th august, ‘17


stay safe + ily🎐

Your weary, tired eyes had finally begun to flutter closed after your phone slipped from your fingers and landed with a quiet thud somewhere in the mass of cotton covers. 11:34 pm, you read through the blurriness of closing eyelids on the insistently ticking clock situated on your bedside table, with the help of the moons bright, glaring optical rays peering in through your open window. 

Then, a faint knock on your bedroom door infiltrated your senses, and your body jolted awake - not expecting someone to be asking for entrance this late at night.

You cleared your throat, leaning up on your elbows as you called out a soft, “Come in,” Squinting your eyes slightly through the shadows eclipsing your room with darkness, you tried to make out who stood in your doorway as the wood opened gently on its hinges.

“H-Hey, sorry, your mum let me in,” Peter’s voice travelled through the dark and met your ears as a sigh of relief slipped past your lips.

“Peter? What’re you doing here?” You carefully climbed out of the warm solace of your duvet and met your boyfriend half way, letting him gently clasp you by the waist and bring your body closer into his safe vicinity as he pressed a quick, sweet kiss to your lips.

“I have something to tell you,” The words uttered from the boy in front of you would’ve worried you greatly had it not been for the pure excitement etched onto his glowing features and the hyper bounce in his movement as he pivoted on his heels and quietly closed the door.

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This composite NASA image of the spiral galaxy M81, located about 12 million light years away, includes X-ray data from the Chandra X-ray Observatory (blue), optical data from the Hubble Space Telescope (green), infrared data from the Spitzer Space Telescope (pink) and ultraviolet data from GALEX (purple). The inset shows a close-up of the Chandra image. At the center of M81 is a supermassive black hole that is about 70 million times more massive than the Sun.

A new study using data from Chandra and ground-based telescopes, combined with detailed theoretical models, shows that the supermassive black hole in M81 feeds just like stellar mass black holes, with masses of only about ten times that of the Sun. This discovery supports the implication of Einstein’s relativity theory that black holes of all sizes have similar properties, and will be useful for predicting the properties of a conjectured new class of black holes.

In addition to Chandra, three radio arrays (the Giant Meterwave Radio Telescope, the Very Large Array and the Very Long Baseline Array), two millimeter telescopes (the Plateau de Bure Interferometer and the Submillimeter Array), and Lick Observatory in the optical were used to monitor M81. These observations were made simultaneously to ensure that brightness variations because of changes in feeding rates did not confuse the results. Chandra is the only X-ray satellite able to isolate the faint X-rays of the black hole from the emission of the rest of the galaxy.

The supermassive black hole in M81 generates energy and radiation as it pulls gas in the central region of the galaxy inwards at high speed. Therefore, the model that Markoff and her colleagues used to study the black holes includes a faint disk of material spinning around the black hole. This structure would mainly produce X-rays and optical light. A region of hot gas around the black hole would be seen largely in ultraviolet and X-ray light. A large contribution to both the radio and X-ray light comes from jets generated by the black hole. Multiwavelength data is needed to disentangle these overlapping sources of light.


Concave - CONvering Mirror
Convex - Diverging Mirror

1/o + 1/i = 1/f = 2/r         f = r/2  or  1/2r 

o > r  Real, INverted, Reduced 

o = r  Real, INverted, Same Size

r > o > f  Real, INverted, Enlarged 

o < f  Virtual, UPright, ENLarged

o = f  i @ infinity 

Real Images = Inverted 

Virtual Images = Upright 

Convex Lenses ~ ConCave Mirror Except:

  • Real Image on OPPOSITE side of Lens as Object, Virtual Images on SAME side as object

Concave Lenses ~ ConVex Mirrors (Diverging- Virtual UPright) Except:

  • Virtual image formed by Lens is on SAME side of lens as object 

Farsighted = Converging Lens (reading glasses)

Nearsighted = Diverging Lens


Convergers = + Focal Point, Real, Inverted, Image on side of Observer 

  • if o < f —> rules for diverters apply 

Divergers = - Focal point, Virtual, Upright, Reduced, Image NOT on side as observer 



** Summary: Deep inside the remains of an exploded star lies a twisted knot of newly minted molecules and dust. Using ALMA, astronomers mapped the location of these new molecules to create a high-resolution 3-D image of this “dust factory,” providing new insights into the relationship between a young supernova remnant and its galaxy. **

Supernovas – the violent endings of the brief yet brilliant lives of massive stars – are among the most cataclysmic events in the cosmos. Though supernovas mark the death of stars, they also trigger the birth of new elements and the formation of new molecules.

In February of 1987, astronomers witnessed one of these events unfold inside the Large Magellanic Cloud, a tiny dwarf galaxy located approximately 160,000 light-years from Earth.

Over the next 30 years, observations of the remnant of that explosion revealed never-before-seen details about the death of stars and how atoms created in those stars – like carbon, oxygen, and nitrogen – spill out into space and combine to form new molecules and dust. These microscopic particles may eventually find their way into future generations of stars and planets.

Recently, astronomers used the Atacama Large Millimeter/submillimeter Array (ALMA) to probe the heart of this supernova, named SN 1987A. ALMA’s ability to see remarkably fine details allowed the researchers to produce an intricate 3-D rendering of newly formed molecules inside the supernova remnant. These results are published in the Astrophysical Journal Letters.

The researchers also discovered a variety of previously undetected molecules in the remnant. These results appear in the Monthly Notices of the Royal Astronomical Society.

“When this supernova exploded, now more than 30 years ago, astronomers knew much less about the way these events reshape interstellar space and how the hot, glowing debris from an exploded star eventually cools and produces new molecules,” said Rémy Indebetouw, an astronomer at the University of Virginia and the National Radio Astronomy Observatory (NRAO) in Charlottesville. “Thanks to ALMA, we can finally see cold ‘star dust’ as it forms, revealing important insights into the original star itself and the way supernovas create the basic building blocks of planets.”

Supernovas – Star Death to Dust Birth

Prior to ongoing investigations of SN 1987A, there was only so much astronomers could say about the impact of supernovas on their interstellar neighborhoods.

It was well understood that massive stars, those approximately 10 times the mass of our Sun or more, ended their lives in spectacular fashion.

When these stars run out of fuel, there is no longer enough heat and energy to fight back against the force of gravity. The outer reaches of the star, once held up by the power of fusion, then come crashing down on the core with tremendous force. The rebound of this collapse triggers a powerful explosion that blasts material into space.

As the endpoint of massive stars, scientists have learned that supernovas have far-reaching effects on their home galaxies. “The reason some galaxies have the appearance that they do today is in large part because of the supernovas that have occurred in them,” Indebetouw said. “Though less than ten percent of stars become supernovas, they nonetheless are key to the evolution of galaxies.”

Throughout the observable universe, supernovas are quite common, but since they appear – on average – about once every 50 years in a galaxy the size of the Milky Way, astronomers have precious few opportunities to study one from its first detonation to the point where it cools enough to form new molecules. Though SN 1987A is not in our home galaxy, it is still close enough for ALMA and other telescopes to study in fine detail.

Capturing 3-D Image of SN1987A with ALMA

For decades, radio, optical, and even X-ray observatories have studied SN 1987A, but obscuring dust in the remnant made it difficult to analyze the supernova’s innermost core. ALMA’s ability to observe at millimeter wavelengths – a region of the electromagnetic spectrum between infrared and radio light – make it possible to see through the intervening dust. The researchers were then able to study the abundance and location of newly formed molecules – especially silicon monoxide (SiO) and carbon monoxide (CO), which shine brightly at the short submillimeter wavelengths that ALMA can perceive.

The new ALMA image and animation show vast new stores of SiO and CO in discrete, tangled clumps within the core of SN 1987A. Scientists previously modeled how and where these molecules would appear. With ALMA, the researchers finally were able to capture images with high enough resolution to confirm the structure inside the remnant and test those models.

Aside from obtaining this 3-D image of SN 1987A, the ALMA data also reveal compelling details about how its physical conditions have changed and continue to change over time. These observations also provide insights into the physical instabilities inside a supernova.

New Insights from SN 1987A

Earlier observations with ALMA verified that SN 1987A produced a massive amount of dust. The new observations provide even more details on how the supernova made the dust as well as the type of molecules found in the remnant.

“One of our goals was to observe SN 1987A in a blind search for other molecules,” said Indebetouw. “We expected to find carbon monoxide and silicon monoxide, since we had previously detected these molecules.” The astronomers, however, were excited to find the previously undetected molecules formyl cation (HCO+) and sulfur monoxide (SO).

“These molecules had never been detected in a young supernova remnant before,” noted Indebetouw. “HCO+ is especially interesting because its formation requires particularly vigorous mixing during the explosion.” Stars forge elements in discrete onion-like layers. As a star goes supernova, these once well-defined bands undergo violent mixing, helping to create the environment necessary for molecule and dust formation.

The astronomers estimate that about 1 in 1,000 silicon atoms from the exploded star is now found in free-floating SiO molecules. The overwhelming majority of the silicon has already been incorporated into dust grains. Even the small amount of SiO that is present is 100 times greater than predicted by dust-formation models. These new observations will aid astronomers in refining their models.

These observations also find that ten percent or more of the carbon inside the remnant is currently in CO molecules. Only a few out of every million carbon atoms are in HCO+ molecules.

New Questions and Future Research

Even though the new ALMA observations shed important light on SN 1987A, there are still several questions that remain. Exactly how abundant are the molecules of HCO+ and SO? Are there other molecules that have yet to be detected? How will the 3-D structure of SN 1987A continue to change over time?

Future ALMA observations at different wavelengths may also help determine what sort of compact object – a pulsar or neutron star – resides at the center of the remnant. The supernova likely created one of these dense stellar objects, but as yet none has been detected.

TOP IMAGE….Supernova 1987A in the Large Magellanic Cloud

UPPER IMAGE….close up of Supernova 1987A

CENTRE IMAGE….Astronomers combined observations from three different observatories to produce this colorful, multiwavelength image of the intricate remains of Supernova 1987A.The red color shows newly formed dust in the center of the supernova remnant, taken at submillimeter wavelengths by the Atacama Large Millimeter/submillimeter Array (ALMA) telescope in Chile.The green and blue hues reveal where the expanding shock wave from the exploded star is colliding with a ring of material around the supernova. The green represents the glow of visible light, captured by NASA’s Hubble Space Telescope. The blue color reveals the hottest gas and is based on data from NASA’s Chandra X-ray Observatory.The ring was initially made to glow by the flash of light from the original explosion. Over subsequent years the ring material has brightened considerably as the explosion’s shock wave slams into it. Supernova 1987A resides 163,000 light-years away in the Large Magellanic Cloud, where a firestorm of star birth is taking place.

LOWER IMAGE….This artist’s illustration of Supernova 1987A reveals the cold, inner regions of the exploded star’s remnants (red) where tremendous amounts of dust were detected and imaged by ALMA. This inner region is contrasted with the outer shell (blue), where the energy from the supernova is colliding (green) with the envelope of gas ejected from the star prior to its powerful detonation.
Credit: A. Angelich; NRAO/AUI/NSF

BOTTOM IMAGE….Remnant of Supernova 1987A as seen by ALMA. Purple area indicates emission from SiO molecules. Yellow area is emission from CO molecules. The blue ring is Hubble data that has been artificially expanded into 3-D.
Credit: ALMA (ESO/NAOJ/NRAO); R. Indebetouw; NASA/ESA Hubble

Gravity’s Grin

Albert Einstein's general theory of relativity, published over 100 years ago, predicted the phenomenon of gravitational lensing. And that’s what gives these distant galaxies such a whimsical appearance, seen through the looking glass of X-ray and optical image data from the Chandra and Hubble space telescopes.

Nicknamed the Cheshire Cat galaxy group, the group’s two large elliptical galaxies are suggestively framed by arcs. The arcs are optical images of distant background galaxies lensed by the foreground group’s total distribution of gravitational mass. Of course, that gravitational mass is dominated by dark matter. The two large elliptical “eye” galaxies represent the brightest members of their own galaxy groups which are merging. Their relative collisional speed of nearly 1,350 kilometers/second heats gas to millions of degrees producing the X-ray glow shown in purple hues. Curiouser about galaxy group mergers? The Cheshire Cat group grins in the constellation Ursa Major, some 4.6 billion light-years away.

Image Credit: X-ray - NASA / CXC / J. Irwin et al. ; Optical - NASA/STScI

*shared from the nasa app*

What is a gamma-ray burst?

Gamma-ray bursts (GRBs) are flashes of gamma rays associated with extremely energetic explosions that have been observed in distant galaxies. They are the brightest electromagnetic events known to occur in the universe. Bursts can last from ten milliseconds to several minutes. The initial burst is usually followed by a longer-lived “afterglow” emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).

Most observed GRBs are believed to consist of a narrow beam of intense radiation released during a supernova or hypernova as a rapidly rotating, high-mass star collapses to form a neutron star, quark star, or black hole. A subclass of GRBs (the “short” bursts) appear to originate from a different process - this may be due to the merger of binary neutron stars. The cause of the precursor burst observed in some of these short events may be due to the development of a resonance between the crust and core of such stars as a result of the massive tidal forces experienced in the seconds leading up to their collision, causing the entire crust of the star to shatter.

Gamma-ray bursts are thought to be highly focused explosions, with most of the explosion energy collimated into a narrow jet traveling at speeds exceeding 99.995% of the speed of light. The approximate angular width of the jet (that is, the degree of spread of the beam) can be estimated directly by observing the achromatic “jet breaks” in afterglow light curves: a time after which the slowly decaying afterglow begins to fade rapidly as the jet slows and can no longer beam its radiation as effectively

Image credit: NASA/Swift/Cruz deWilde

Infrared, X-ray & Optical Images of Centaurus A

Centaurus A is the fifth brightest galaxy in the sky – making it an ideal target for amateur astronomers – and is famous for the dust lane across its middle and a giant jet blasting away from the supermassive black hole at its center.  Cen A is an active galaxy about 12 million light years from Earth.

Credit: X-ray: NASA/CXC/SAO; Optical: Rolf Olsen; Infrared: NASA/JPL-Caltech


NGC 3627: Revealing Hidden Black Holes

The spiral galaxy NGC 3627 is located about 30 million light years from Earth. This composite image includes X-ray data from NASA’s Chandra X-ray Observatory (blue), infrared data from the Spitzer Space Telescope (red), and optical data from the Hubble Space Telescope and the Very Large Telescope (yellow). The inset shows the central region, which contains a bright X-ray source that is likely powered by material falling onto a supermassive black hole.
A search using archival data from previous Chandra observations of a sample of 62 nearby galaxies has shown that 37 of the galaxies, including NGC 3627, contain X-ray sources in their centers. Most of these sources are likely powered by central supermassive black holes. The survey, which also used data from the Spitzer Infrared Nearby Galaxy Survey, found that seven of the 37 sources are new supermassive black hole candidates.

Confirming previous Chandra results, this study finds the fraction of galaxies found to be hosting supermassive black holes is much higher than found with optical searches. This shows the ability of X-ray observations to find black holes in galaxies where relatively low-level black hole activity has either been hidden by obscuring material or washed out by the bright optical light of the galaxy.

The combined X-ray and infrared data suggest that the nuclear activity in a galaxy is not necessarily related to the amount of star-formation in the galaxy, contrary to some early claims. In contrast, these new results suggest that the mass of the supermassive black hole and the rate at which the black hole accretes matter are both greater for galaxies with greater total masses.

A paper describing these results was published in the April 10, 2011 issue of The Astrophysical Journal. The authors are Catherine Grier and Smita Mathur of The Ohio State University in Columbus, OH; Himel GHosh of CNRS/CEA-Saclay in Guf-sur-Yvette, France and Laura Ferrarese from Herzberg Institute of Astrophysics in Victoria, Canada.

NASA’s Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra’s science and flight operations from Cambridge, Mass.

Image Credit: NASA/CXC/Ohio State Univ./C.Grier et al.; Optical: NASA/STScI, ESO/WFI; Infrared: NASA/JPL-Caltech


BMW CONCEPT Iconic Organic Laserlight System, shown on a 2015 M4 at CES 2015

Inside the laser headlights, the “coherent” monochromatic blue laser light is converted into harmless white light. A special optical system directs the rays from the high-performance diodes onto a phosphor plate inside the light, which converts the beam into a very bright white light that is similar to natural daylight and pleasant to the eye. Despite consuming 30 percent less energy, the parallel light beam is ten times more intense than that produced by halogen, xenon or LED light sources. The most innovative feature had the headlights serving as a driver-assistance feature. BMW’s video showed an instance where a large truck was crowding the lane ahead. The headlights used the car’s camera data to paint lines on the road for the driver, between the truck and the roadside barrier. When the system’s computer determined the space was too narrow for the M4, the system painted a warning sign for the driver not to attempt to pass.