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NASA Reveals Incredible View Inside Superstar Eta Carinae

New findings include Hubble Space Telescope images that show decade-old shells of ionized gas racing away from the largest star at a million miles an hour, and new 3-D models that reveal never-before-seen features of the stars’ interactions.

Eta Carinae is a binary system containing the most luminous and massive star within 10,000 light-years. A long-term study led by astronomers at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, combined data from NASA satellites, ground-based observing campaigns and theoretical modeling to produce the most comprehensive picture of Eta Carinae to date. New findings include Hubble Space Telescope images that show decade-old shells of ionized gas racing away from the largest star at a million miles an hour, and new 3-D models that reveal never-before-seen features of the stars’ interactions.

Located about 7,500 light-years away in the southern constellation of Carina, Eta Carinae comprises two massive stars whose eccentric orbits bring them unusually close every 5.5 years. Both produce powerful gaseous outflows called stellar winds, which enshroud the stars and stymy efforts to directly measure their properties. Astronomers have established that the brighter, cooler primary star has about 90 times the mass of the sun and outshines it by 5 million times. While the properties of its smaller, hotter companion are more contested, Goddard’s Ted Gull and his colleagues think the star has about 30 solar masses and emits a million times the sun’s light.

At closest approach, or periastron, the stars are 140 million miles (225 million kilometers) apart, or about the average distance between Mars and the sun. Astronomers observe dramatic changes in the system during the months before and after periastron. These include X-ray flares, followed by a sudden decline and eventual recovery of X-ray emission; the disappearance and re-emergence of structures near the stars detected at specific wavelengths of visible light; and even a play of light and shadow as the smaller star swings around the primary.

During the past 11 years, spanning three periastron passages, the Goddard group has developed a model based on routine observations of the stars using ground-based telescopes and multiple NASA satellites. According to this model, the interaction of the two stellar winds accounts for many of the periodic changes observed in the system. The winds from each star have markedly different properties: thick and slow for the primary, lean and fast for the hotter companion. The primary’s wind blows at nearly 1 million mph and is especially dense, carrying away the equivalent mass of our sun every thousand years. By contrast, the companion’s wind carries off about 100 times less material than the primary’s, but it races outward as much as six times faster.

The images and video on this page include periastron observations from NASA’s Rossi X-ray Timing Explorer, the X-Ray Telescope aboard NASA’s Swift, the Hubble Space Telescope’s STIS instrument, and computer simulations.

Sharks Are Eating Asia’s Internet

Shark species in the region may be drawn to chow down on undersea cables, which send off electromagnetic waves that can act as shark bait.

If you live in Southeast Asia and can’t stream YouTube videos or access Facebook, sharks may be to blame.

The underwater trans-Pacific cable that provides Internet to most of Southeast Asia broke again yesterday, leaving millions with slow or spotty connectivity. The region faces an estimated repair time of up to a month.

The Asia-America Gateway (AAG), launched in 2009, is an enormous underwater cable line stretching 12,000 miles across the Pacific. It connects 10 points throughout the Pacific islands and Southeast Asia and provides vital connectivity to several countries between Malaysia and California.

But one branch of the $500 million AAG has been continually beset with problems. The segment of the cable that runs between Vietnam and Hong Kong has ruptured four times within the last six months—twice near Hong Kong and twice near Vietnam. The latest incident occurred yesterday, when the cable broke near the Vietnamese city of Ba Ria.

In addition to Vietnam, the outage effects the cable’s offshoot points further west, which means Internet users in Brunei, Singapore, Thailand, and Malaysia are also feeling the slow-down. Although these other countries rely on the cable, it is managed by one Vietnamese telecommunications company.

Investigators have not confirmed a reason for the latest rupture. One common explanation in these cases is that anchors from passing fishing trawlers snagged the cable and caused damage. Increasingly, however, cable watchers believe that the problem may be sharks.

Shark species in the region, these experts say, may be drawn to chow down on the cables, which send off electromagnetic waves that can act as sharkbait. One theory holds that sharks mistake the cables for the bioelectric fields surrounding schools of fish. Others suggest that perhaps sharks are merely overly curious.

To prevent sharks from chomping through fragile and expensive fiber-optic wires, Google, which has pledged to collaborate on a similar $300 million undersea cable to Japan, has started wrapping its cables in kevlar.

Watch Airbus Risk $1.5B in Insane Jumbo Jet Stunt

Airbus flew five of its new A350 XWB wide-body passenger jets in an epic stunt formation for a once-in-a-lifetime photo shoot.

The five test and development A350-900s took to the skies for a formation flight in September 2014, bringing together all of the aircraft used for Airbus’ successful campaign leading to certification of this latest Airbus widebody jetliner.

The company put their test pilots’ skill to the ultimate test in a promo video designed to show off its new A350 XWB passenger jet. The beautifully choreographed stunt involved all five of the brand-new A350-900 jets, as well as two chase planes and a helicopter flying in a formation typically pulled off by high performance fighter jets.

The costs of the shoot are unknown, but each jet has a list price of $300 million, so it’s safe to assume that well over $1.5 billion of machinery was on the line.

Trippy Spiral Hacks a Hummingbird’s Hover

A moving view, like a trippy morphing spiral, is enough to make a hummingbird unstable. Little is known about how birds use senses to control flight.

If a sipping hummingbird starts to wobble when near a flower, it’s probably not because its nectar has been spiked. A moving view, like a trippy morphing spiral, seems to be enough to make it lose its stability (see video above).

To investigate how Anna’s hummingbirds control their body position, Douglas Altshuler and his team at the University of British Columbia in Canada set up a hummingbird bar in front of a screen with moving patterns. The group found that even minimal background movement affected the birds’ hovering, causing them to wobble back and forth while feeding or to jam their bills in too far, depending on the direction of motion.

Given that the birds’ natural environment is full of moving elements, it is surprising how sensitive they are to movement in their visual field, says the team. Little is known about how birds use their senses to control flight.

The effect, however, doesn’t stop hummingbirds from being spectacular aerial acrobats: Anna’s hummingbirds can shake faster than any other vertebrate and dive at record-breaking speeds.