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Posts Tagged ‘bad astronomy’

Spectacular Fireball Lights Up UK Sky

September 22nd, 2012 09:31 admin View Comments

Earth

The Bad Astronomer writes “An extremely bright meteor burned up over Ireland and the northern UK around 22:00 UTC on Friday night, and was apparently witnessed by thousands of people. It traveled east to west, and was moving relatively slowly. It may have been an actual rock, or it may have been some human-made space debris — a satellite or rocket booster — burning up. Space junk tends to move more slowly, so that’s a potential suspect, though orbiting debris usually moves in the opposite direction. I’m collecting pictures and images on my Bad Astronomy blog.”

Source: Spectacular Fireball Lights Up UK Sky

Study Finds Religion May Be Going “Extinct” in Some Countries

March 22nd, 2011 03:33 admin View Comments

What’s the News: Looking at census data from nine countries, a team of scientists have made the bold assertion that religion is headed for extinction and it’s all based on a mathematical model of the complex social motives behind joining religious groups. As they note in their abstract, “People claiming no religious affiliation constitute the fastest growing ‘religious’ minority in many countries throughout the world.”

How the Heck:

  • The theory behind their model “posits that social groups that have more members are going to be more attractive to join, and … that social groups have a social status or utility,” Richard Wiener from the University of Arizona told the BBC. You could call it the Facebook effect.
  • So they looked at census data spanning the past century from Australia, Austria, Canada, the Czech Republic, Finland, Ireland, the Netherlands, New Zealand and Switzerland, and discovered that an increasing number of people identify themselves as “non-affiliated” with religion. For example, 40% of the Netherlands and 60% of the Czech Republic is unaffiliated.
  • Using a nonlinear dynamics model, which allows researchers to track outcomes from a number of factors, the scientists accounted for the “social and utilitarian merits” of being in a non-religious category, concluding that religion will die in societies wherever non-religious affiliation is more socially useful than religious affiliation—which seems to be the trend in the nine countries studied.

What’s the Context:

Not So Fast: The model’s limitations are many, including its simplistic network structure, as Weiner told the BBC: It assumes that each person is equally influenced by every other person. It also assumes that mere social utility is the driving reason behind people’s religious affiliations, ignoring a slew of other, difficult to measure, non-social factors underlying faith, such as the strength of deeply personal religious convictions and a (potential) basic human tendency to believe in something larger than ourselves. The study is based on the premise that religious networks behave the same was as do speakers of a common language and non-religious social groups, a reasonable but debatable assumption.

Reference: “A mathematical model of social group competition with application to the growth of religious non-affiliation.” Authors: Daniel M. Abrams, Haley A. Yaple, Richard J. Wiener. arXiv:1012.1375

Image: flickr / DominusVobiscum

Source: Study Finds Religion May Be Going “Extinct” in Some Countries

Stardust Spacecraft Sends Home Close-Ups of a Comet

February 15th, 2011 02:15 admin View Comments

Well, NASA’s Valentine’s date seems to have gone off without a hitch. Last night the Stardust-NExT probe passed within 110 miles of the comet Tempel 1, and snapped plenty of pictures during its rendezvous. The mission’s main objective was to record the results of an experiment conducted by another spacecraft, Deep Impact, which hurled an impactor at Tempel 1 back in 2005. Researchers hoped Stardust would catch a glimpse of the man-made crater.

As Phil Plait writes:

The whole point here was to see the impact crater from 2005, and Stardust was able to do that. It’s difficult to see in these images here, but Pete Schultz, an impact specialist with the mission, said the crater is about 150 meters across and has a central peak, indicating material fell back to the comet. The crater wasn’t as obvious as expected, but is about the right size given the impactor speed, mass, and angle of impact.

Head over to Bad Astronomy for more details, and for a nice animation of the flyby.

Image: NASA/JPL-Caltech/Cornell

Source: Stardust Spacecraft Sends Home Close-Ups of a Comet

Itty Bitty Galaxy Home to Gargantuan Supermassive Black Hole

January 11th, 2011 01:35 admin View Comments

One of these things is not like the other: Astronomers have spotted a dwarf galaxy that spans just 3,000 light years across (as opposed to our Milky Way’s diameter of 100,000 light years), but hosts an outsize supermassive black hole for its puny size.

From DISCOVER blogger Phil Plait:

Some smaller galaxies have supermassive black holes as well, but in general these dwarf galaxies have some structure to them, with a well-defined core. Henize 2-10, as you can see, it a mess! It doesn’t have much overall structure, which is why it’s classified as an irregular galaxy. The thinking for big galaxies is that the black hole forms at the same time as the galaxy itself, and to regulate the growth of each other. When you look at lots of big galaxies, there’s a pretty clear overall correlation between the mass of the black hole and the galaxy around it.

So it’s pretty weird that Henize 2-10 has a supermassive black hole at all, but it turns out the hole is also about a million times the mass of the Sun — that’s pretty freakin’ big for such a tiny galaxy! That’s 1/4 the mass of our own black hole, in a galaxy that itself is far smaller than ours.

For more details about this weird galaxy, check out the rest of this post at Bad Astronomy. And for more galaxy-black hole weirdness, read last week’s 80beats post about whether mergers of galaxies truly cause supermassive black holes to become hyperactive.

Image: Reines, et al., NRAO/AUI/NSF, NASA

Source: Itty Bitty Galaxy Home to Gargantuan Supermassive Black Hole

Kepler Finds a Super-Small, Super-Hot Rocky Exoplanet

January 10th, 2011 01:46 admin View Comments

The Kepler space telescope, launched nearly two years ago, has already proven its worth as an exoplanet hunter many times over. But the discoveries keep on coming. NASA just announced that Kepler has found its first rocky planet–and that the rocky world is only 1.4 times the size of Earth, making it the smallest exoplanet ever found.

Phil Plait explains that this nearly Earth-sized isn’t actually Earth-like and habitable:

[I]t orbits extremely close in to its star, circling over the star’s surface at a distance of roughly 3 million kilometers (1.8 million miles) — amazingly, it takes less than an Earth day to make one circuit. But being that close to a star comes at a price: the surface temperature of the planet must be several thousand degrees!

The planet, Kepler-10b, may not be habitable to life as we know it, but Plait is still plenty excited. Get the rest of the story on how the planet was found and what its discovery means over at Bad Astronomy.

Source: Kepler Finds a Super-Small, Super-Hot Rocky Exoplanet

BMJ: Vaccine-Autism Researcher Andrew Wakefield is a “Fraud”

January 6th, 2011 01:55 admin View Comments

More than a dozen years have passed since the 1998 study in The Lancet in which researcher Andrew Wakefield argued his case that vaccines are the cause of autism. We here at DISCOVER have long considered his claims to be dubious and damaging to public health, but in the last few years the edifice upon which the anti-vaccination movement was built has been falling down. In 2004 most of the coauthors on the Wakefield study retracted the interpretation section of the paper, and early last year The Lancet officially retracted the entire paper. Now, this week, the British Medical Journal’s investigation calls Wakefield an out-and-out “fraud.”

From Phil Plait:

Of course, the word “fraud” implies intent; when writing about Wakefield I had my suspicions, but always wrote as if he were just wrong, and not deliberately lying to vulnerable parents.

But deliberate fraud is what he’s now accused of. Brian Deer, an investigative journalist, has written a multi-part series on the BMJ site which slams Wakefield. Fiona Godlee, BMJ’s editor-in-chief, also writes about this… and just to be clear, she uses the word “fraud” nine times in her editorial.

Brian Deer’s article on BMJ is nothing short of a tour-de-force, and is a horrifying tale of how Wakefield allegedly falsified medical research deliberately while operating under a huge conflict of interest. Deer’s article is meticulously referenced and footnoted… but still, I know this won’t stop the antivaxxers.

Read the rest of Phil’s post about this at Bad Astronomy.

Image: iStockphoto

Source: BMJ: Vaccine-Autism Researcher Andrew Wakefield is a “Fraud”

Double Eclipse Photographed, Sun, Moon, and ISS

January 4th, 2011 01:44 admin View Comments

The Bad Astronomer writes “The exceptionally talented astrophotographer Thierry Legault captured a picture extraordinary even for him: the space station passing in front of the Sun while the Sun was being partially eclipsed by the Moon! He traveled all the way from France to the Sultanate of Oman to take this amazing shot. I have more information about the picture itself on the Bad Astronomy blog, but you should go to Thierry’s website to see more amazing pictures he’s taken over the years. They’re simply jaw-dropping.”

Source: Double Eclipse Photographed, Sun, Moon, and ISS

Cassini Catches a Glimpse of an Enormous Storm on Saturn

December 28th, 2010 12:48 admin View Comments

A new sight appeared on Saturn earlier this month: A massive, swirling storm with a tail that cuts across the gas giant. Amateur astronomer Anthony Wesley, who was the first to spot the Earth-sized scar on Jupiter last summer, took the first pictures of this storm. And then on Christmas Eve the Cassini spacecraft beamed home its own ravishing images.

From Phil Plait:

The spacecraft took images of the planet on December 24th, returning — as usual — jaw-dropping pictures of Saturn showing the storm. This image, taken with a blue filter, shows the storm clearly. The main spot is huge, about 6,000 km (3600 miles) across — half the size of Earth! Including the tail streaming off to the right, the whole system is over 60,000 km (36,000 miles) long.

There’s an added bonus in these images: the shadow of the rings on the planet’s clouds is obvious, but the rings are nearly invisible! You can just make out the rings as a thin line going horizontally across Saturn in the first image. These pictures were snapped when Cassini was almost directly above the rings, which are so thin they vanish when seen edge-on. Actually, that works out well as otherwise they might interfere with the view of the storm in these shots.

For more details, check out the rest of Phil’s post at Bad Astronomy.

Image: NASA

Source: Cassini Catches a Glimpse of an Enormous Storm on Saturn

Voyager Spacecraft Prepares to Exit the Solar System

December 14th, 2010 12:32 admin View Comments

voyager-1Into the great unknown, into the wild blue yonder, past the second star on the right and straight on till morning: That’s where NASA’s Voyager 1 is heading. The remarkable spacecraft was launched 33 years ago, and it’s now reaching the edge of our solar system. Within a few years, NASA says, it will enter interstellar space.

Phil Plait reports on how researchers realized they’d reached a milestone in Voyager 1’s journey:

Over all those years, there has been one constant in the Voyager flight: the solar wind blowing past it. This stream of subatomic particles leaves the Sun at hundreds of kilometers per second, much faster than Voyager. But now, after 33 years, that has changed: at 17 billion kilometers (10.6 billion miles) from the Sun, the spacecraft has reached the point where the solar wind has slowed to a stop. Literally, the wind is no longer at Voyager’s back.

Read the rest of his post at Bad Astronomy.

Source: Voyager Spacecraft Prepares to Exit the Solar System

Super-Hot Super-Earth May Have an Atmosphere of Steam

December 1st, 2010 12:35 admin View Comments

SteamyexoplanetFrom Phil Plait:

Last year, astronomers discovered a remarkable planet orbiting another star: it has a mass and radius that puts it in the “super-Earth” category — meaning it’s more like the Earth than a giant Jupiter-like planet. Today, it has been announced that astronomers have been able to analyze the atmosphere of the planet (the very first time this has ever been accomplished for a super-Earth), and what they found is astonishing: the air of the planet is either shrouded in thick haze, or it’s loaded with water vapor… in other words, steam!

Astronomers observed the planet when it passed in front of the star, analyzing the light very carefully. As starlight passes through the planet’s atmosphere, certain colors of it get absorbed, and these are like fingerprints that can be used to figure out the atmospheric composition. Most models predicted a heavy hydrogen content, but the observations indicate none is there! That means either there are thick layers of haze in the upper atmosphere of the planet, obscuring any hydrogen below them — much like Venus or Saturn’s moon Titan, blocking the view lower down — or there is a vast amount of water in the planet’s air. And at a temperature of 200° C, that water would be in the form of vapor. In other words, steam.

For the full scoop on GJ 1214b, located about 42 light years from here, check out Phil’s entire post at Bad Astronomy.

Image: ESO

Source: Super-Hot Super-Earth May Have an Atmosphere of Steam

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