Black Holes

This first video is for the Through the Wormhole. The rest are meant to supplement your interest or provide other explanations.

Through The Wormhole: The Riddle of Black Holes

Black Holes (BBC)

Cosmic Journeys: The Largest Black Holes in the Universe

Who’s Afraid of a Big Black Hole?

How to Time Travel

Einstein-Rosen Bridge

Michio Kaku – Physics of the Impossible – How to Travel Through Time

Michio Kaku – Physics of The Impossible – How to Travel to Parallel Universe

New Telescope Optics Can Directly View Exoplanets By Hiding Interfering Starlight

By Rebecca Boyle
June 11th, 2012

Sifting Starlight These two images show HD 157728, a nearby star 1.5 times larger than the sun. The star is centered in both images, and its light has been mostly removed by an adaptive optics system and coronagraph belonging to Project 1640, which uses new technology on the Palomar Observatory’s 200-inch Hale telescope to spot planets.

For now, the thousands of potential exoplanets discovered in the past two years are little more than curvy dips on a graph. Astronomers using the Kepler Space Telescope pick them out by examining the way they blot out their own stars’ light as they move through their orbits. But if astronomers could block out the stars themselves, they may be able to see the planets directly. A new adaptive optics system on the storied Palomar Observatory just started doing that — it’s the first of its kind capable of spotting planets outside our solar system.

The new system is called Project 1640, and it creates dark holes around stars that may harbor planets. It removes the blinding glare of starlight so astronomers can see the exoplanets. This is extremely hard to do, said Charles Beichman, executive director of the NASA Exoplanet Science Institute at Caltech. “Imagine trying to see a firefly whirling around a searchlight more than a thousand miles away,” he said in a statement.

Coronagraphs are used to block out starlight so scientists can see what lurks around the stars. But even when you block the brightest light, about half of it can still fuzz up an image, creating speckles and background light that will interfere with images of potential planets. To address this speckly starlight, Project 1640 uses the world’s most advanced adaptive optics system, and four separate instruments on Palomar’s 200-inch Hale telescope that image the infrared light generated by young, warm planets orbiting stars.

Beta Pictoris: This image of the star Beta Pictoris shows a huge planet orbiting the star. The pale blue dots at the center are the planet, shown in two orbital configurations. The black disk is where the star would be; it’s blocked by a coronagraph. But more starlight is visible at the sides, which could potentially be outshining other, smaller planets in this solar system. A new adaptive optics system can remove this shine, too, unveiling new worlds around distant stars.

Its adaptive optics system can make more than 7 million active mirror deformations per second, with a precision level better than one nanometer. Its wave front sensor, which detects the atmosphere-caused deformations of light hitting the telescope, is also sensitive to a nanometer. As the system detects perturbations in the light waves coming into the telescope, it continually adjusts and deforms to block out the light as effectively as possible.

The system can resolve objects 1 million to 10 million times fainter than the object at the center of the image, which is usually the star. With that level of sensitivity, astronomers may be able to see planets.

Now that it’s up and running, as of late June, astronomers have embarked on a three-year survey of hot young stars. The planets they will detect with this method will probably be large hot Jupiters, and so unlikely to contain life — but their moons potentially could. In any event, it’s likely to be yet another major player in the planet-hunting business.

A nearby star may have more planets than we do!

By Phil Plait

HD 10180 is a star that’s nearly the Sun’s twin: it’s very close in mass, temperature, brightness, and even chemical content of our friendly neighborhood star. But in this case of stellar sibling rivalry, HD 10180 may have the upper hand: a new analysis of observations of the star indicate it may have nine planets!

In a new report accepted for publication in the journal Astronomy and Astrophysics, an astronomer re-analyzed data of the star taken with the High Accuracy Radial Velocity Planet Searcher (HARPS), an exquisitely high-precision camera mounted on a 3.6 meter telescope in Chile. HARPS has been observing HD 10180 for years; the star is a mere 130 light years away, making it bright and easy to study. The observations look to see if the star exhibits a periodic shift in its light: a Doppler shift as planets circle it, tugging it one way and another.

Six clear Doppler shift signals were found in the original analysis: six planets, five of which have masses ranging from 12 – 25 times that of the Earth (making them more like Neptune than our own comfortable planet), and a sixth that was bigger yet, 65 times Earth’s mass (more like Saturn than Neptune). These planets orbit HD 10180 with periods of 5 – 2000 days. A seventh possible planet was detected, but the data weren’t strong enough to make a solid claim.

The new analysis looks at the old data in a different way, examining it using different statistical methods. Not only are the six planets seen in the new results, but the seventh is confirmed, as well as finding two additional planets in the data. If this result pans out, that means HD 10180 has nine planets, more than our solar system does!

The three additional planets have masses of 1.3, 1.9, and 5.1 times that of Earth, and orbit the star with periods (think of that as the planets’ years) of 1.2, 10, and 68 days, respectively.

Those first two are pretty firmly in the Earth-mass range, what astronomers call “super Earths”. However, Earth-like they ain’t: they’d be cooked by the star. The first is only 3 million km (less than 2 million miles) from HD 10180, and the second barely any cooler at about 14 million km (8 million miles). This is much closer to the star than Mercury is to the Sun, and remember HD 10180 is very much like the Sun. If those planets are rocky, their surfaces are hot enough to melt tin, zinc, and on that inner planet, maybe even iron.

So yeah, not exactly a fun place to visit.

An added bonus is that the analysis looked at how stable the orbits are over time. Not all orbits are stable; if two planets occupy certain orbits then they can tug on each other enough over time to make the orbits unstable. It’s like pumping your legs on a swing; do it with the right timing and you can change your swing. In this case, the analysis showed the orbits are stable over time. That doesn’t prove the planets exist, but it does add confidence to the analysis.

And if this does all turn out to be correct, it’s amazing! We’ve been detecting planets around other stars for a while now, including those in multiple systems. But those generally have four planets or fewer; even finding six planets around HD 10180 would be a record. With three more, this would put HD 10180 firmly ahead of every other system detected.

Heck, it beats us. Mind you, no matter where you fall in the Pluto planetary club membership debate, these objects are all more massive even than Earth, so they are most assuredly planets.

Even though this system is very alien to ours, with far more massive planets packed more tightly around their star, most of them cooked to boiling, it’s still a very, very encouraging result. 15 years ago we didn’t know of any other planets orbiting other stars. Now we know of hundreds, with thousands more candidates. And many of these are parts of systems, planetary families a bit like our own. We used to wonder if our solar system was the only one like it in the Universe; unique among the stars.

And now we know the answer: No. And that’s a pretty cool thing to know.