Tag: science

An detailed analysis of the tumbling of the asteroid Apophis, detected by radar observations in January, suggests it will be easier to predict the asteroid’s orbit in the future.

10:15 am

The sky isn’t falling: A detailed analysis of the tumbling of the asteroid Apophis, detected by radar observations in January, suggests it will be easier to predict the asteroid’s orbit in the future.

The gentle but persistent nudging [of the Yarkovsky effect] arises when sunlight is absorbed by a rotating object and then reradiated as heat in some other direction. In particular, if Apophis were spinning retrograde (opposite the way Earth does), then over time its orbit would change in a way that increases the chance of impact in 2036. But now we can rest easy, because Apophis appears to be tumbling as it orbits the Sun. That’s the conclusion reached by a team of telescopic observers who monitored the asteroid’s light curve as it passed near Earth in January. Apophis is spinning around two axes at the same time, implying that any Sun-warmed surfaces are radiating heat in all directions, not just one in particular.

It is very difficult to measure the Yarkovsky effect, thus making it very difficult to precisely calculate the orbits of many near Earth asteroids. In the case of Apophis, however, it appears the astronomers have gotten a good handle on the problem.

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Hubble has taken a spectacular close-up image of the Horsehead Nebula.

9:46 am

A horsehead of another color: Hubble has taken a spectacular close-up image of the Horsehead Nebula.

Also, if you want to find out exactly how powerful Hubble is in comparison with both ground-based and other space telescopes, check out the video provided by this press release for the new images by the Herschel Space Telescope of the Horsehead Nebula that were also released today. Herschel, which works in the far-infrared, produces good data and information that Hubble cannot, but its imagery cannot compare.

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Using Kepler astronomers have found a solar system with five terrestrial-type planets, with two in the habitable zone.

11:23 am

Eden? Using Kepler astronomers have found a solar system with five terrestrial-type planets, with two in the habitable zone.

Using observations gathered by NASA’s Kepler Mission, the team, led by William Borucki of the NASA Ames Research Center, found five planets orbiting a Sun-like star called Kepler-62. Four of these planets are so-called super-Earths, larger than our own planet, but smaller than even the smallest ice giant planet in our Solar System. These new super-Earths have radii of 1.3, 1.4, 1.6, and 1.9 times that of Earth. In addition, one of the five was a roughly Mars-sized planet, half the size of Earth. …

The two super-Earths with radii of 1.4 and 1.6 Earth radii orbit their star at distances where they receive about 41% and 120%, respectively, of the warmth from their star that the Earth receives from the Sun. The planets are thus in the star’s habitable zone; they have the right temperatures to maintain liquid water on their surfaces and are theoretically hospitable to life.

Theoretical modeling of the super-Earth planets, Kepler-62e and Kepler-62f, suggests that both could be solid, either rocky–or rocky with frozen water.

This is big news. Additional info can be found here and here.

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The International Astronomical Union has issued a press release condemning the commercial efforts of private companies to issue names for exoplanets.

11:51 am

Turf war! The International Astronomical Union has issued a press release condemning the commercial efforts of private companies to issue names for exoplanets.

Recently, an organisation has invited the public to purchase both nomination proposals for exoplanets, and rights to vote for the suggested names. In return, the purchaser receives a certificate commemorating the validity and credibility of the nomination. Such certificates are misleading, as these campaigns have no bearing on the official naming process — they will not lead to an officially-recognised exoplanet name, despite the price paid or the number of votes accrued.
… [snip]
To make this possible, the IAU acts as a single arbiter of the naming process, and is advised and supported by astronomers within different fields. As an international scientific organisation, it dissociates itself entirely from the commercial practice of selling names of planets, stars or or even “real estate” on other planets or moons. These practices will not be recognised by the IAU and their alternative naming schemes cannot be adopted.

Well la-dee-da, how dare anyone else name anything ever in space!

The truth is, the IAU was originally given this function by astronomers to coordinate the naming of obscure astronomical objects, not to provide the official names for every object and feature that will ever be discovered in space. And though the IAU does tend to favor the choices of discoverers, it has in the past also ignored their wishes. (See for example my book Genesis: the Story of Apollo 8, where the IAU rejected the names chosen by the Apollo 8 astronauts, even though those astronauts were the first to actually go and see these features.)

In the end, the names of important features in space will be chosen by those who live there.

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Despite a rest, Kepler’s problematic gyroscope is still having problems.

9:26 am

Despite a rest, Kepler’s problematic gyroscope is still having problems.

Three of the wheels are needed for Kepler’s 3.1-foot telescope to have enough sensitivity to detect the minuscule signatures of Earth-sized planets. In an exercise of caution, mission managers switched off Kepler’s reaction wheels for 10 days in January, hoping the break would redistribute lubricant inside the wheel assemblies, reducing friction and allowing the units to cool down.

But friction in wheel no. 4, which has showed friction for much of Kepler’s mission, actually increased in the month following the “wheel rest” period.

The telescope originally had four wheels. One has failed, with a second showing signs of failure. If it goes, the spacecraft will no longer be able to point with enough accuracy to do its primary mission. They might be able to use it to some observations, but its design is such that even these will be of limited value.

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Global warming: time to rein back on doom and gloom?

1:57 pm

From a global warming advocate: Global warming: time to rein back on doom and gloom?

Prediction, as they say, is tough, especially when it’s about the future – and that’s especially true when it comes to the climate, whose complexity we only partially understand. It is, as we all know, naturally immensely variable. And the effect of human intervention is subject to long timelags: it will be decades, even centuries, before the full consequences of today’s emissions of carbon dioxide become clear.

As a result, scientists and policymakers draw on the past to predict the future. Until now, they have therefore placed much weight on the rapid temperature increases in the Eighties and Nineties. But for at least a decade, these have dramatically slowed, even as carbon dioxide emissions have continued to increase. [emphasis mine]

Or as I like to say, every climate model proposed by every global warming scientist has been proven wrong. They all predicted the climate would warm in lockstep with the increase in CO2. It hasn’t.

This is not to say the climate hasn’t warmed in the past five centuries (though some of the data used in for the past 150 years is sadly suspect). What isn’t clear is why. It might be the rise in carbon dioxide. It might also simply be the lingering warming the Earth is experiencing as the last ice age ends. Or it might be because of the Sun.

The field of climate science is very complex, confusing, and in its infancy. We just don’t know yet, and anyone who says they do is not a good scientist.

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The weak solar maximum continues

10:27 am

Late last night NOAA released its monthly update of the Sun’s sunspot cycle, covering the period of March 2013. As I have done every month for the past three years, I am posting this latest graph, with annotations to give it context, below the fold.

While the Sun’s output of sunspots increased in March, it did not do so with much vigor, with the numbers still far below all predictions while also showing an overall decline since a single strong peak in October 2011.

» Read more

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New data from Curiosity has further confirmed that the atmosphere of Mars was once much thicker, and that the remaining atmosphere is still dynamic.

9:45 am

New data from Curiosity has further confirmed that the atmosphere of Mars was once much thicker, and that the remaining atmosphere is still dynamic.

The two most interesting bits of data is that the temperature has been steadily climbing in Gale Crater, and that the humidity has shown significant shifts, depending on the rover’s location as it has traveled through the crater.

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The location of the volcanoes on Titan are not where scientists had expected them to be.

9:30 am

The uncertainty of science: The location of the volcanoes on Titan are not where scientists had expected them to be.

As Io moves closer to Jupiter, the planet’s powerful gravity pulls hard on the moon, deforming it. This force decreases as Io retreats, and the moon bounces back. This cycle of flexing creates friction in Io’s interior, which in turn generates enormous amounts of volcano-driving tidal heat. Common sense suggests that Io’s volcanoes would be located above the spots with the most dramatic internal heating. But Hamilton and his colleagues found that the volcanoes are significantly farther to the east than expected.

Many of the news headlines, including the article above, have trumpeted how the volcanoes on Io are in the wrong place. (See also this article.) Not. The theories were wrong, not the volcanoes. Nature does what it wants to do. It is our job to figure out why.

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Using Hubble astronomers have confirmed that it was a yellow supergiant star that was the progenitor for the nearest supernovae in decades that occurred in 2011.

9:12 am

Using Hubble astronomers have confirmed that it was a yellow supergiant star that was the progenitor for the nearest supernovae in decades, that occurred in 2011 in the Whirlpool Galaxy.

The uncertainty of science: As I noted in 2011 when the yellow supergiant was first detected in pre-explosion images. no theory at that time had ever proposed this kind of star as a supernova progenitor. The discovery has thus required the theorists to come up with new theories.

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The scientists who attempted to re-invent Michael Mann’s hockey stick global warming graph and were caught fudging their data have admitted their data is worthless

12:17 am

The scientists who attempted to re-invent Michael Mann’s hockey stick global warming graph and were caught fudging their data have essentially admitted that their data is worthless.

This is what they say in a FAQ they have added to their paper:

Q: What do paleotemperature reconstructions show about the temperature of the last 100 years?

A: Our global paleotemperature reconstruction includes a so-called “uptick” in temperatures during the 20th century. However, in the paper we make the point that this particular feature is of shorter duration than the inherent smoothing in our statistical averaging procedure, and that it is based on only a few available paleo-reconstructions of the type we used. Thus, the 20th century portion of our paleotemperature stack is not statistically robust, cannot be considered representative of global temperature changes, and therefore is not the basis of any of our conclusions. [emphasis mine]

They are basically admitting that the data used to create the temperature rise of their hockey stick during the past 100 years is unreliable and therefore useless for scientific purposes. Which raises the question: Why did they publish it in the first place? See especially this analysis of this paper and the press’s reaction to it by climate scientists Roger Pielke.

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The Alpha Magnetic Spectrometer on ISS has detected a surplus of positrons, anti-matter electrons, that physicists believe are caused by the existence of dark matter.

9:28 am

The Alpha Magnetic Spectrometer on ISS has detected a surplus of positrons, anti-matter electrons, that physicists believe are caused by the existence of dark matter.

The lead scientist of the experiment also emphasized that dark matter is not the only possible explanation, and that “The detailed interpretation of our data probably will have many theories.”

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Astronomers watch the central supermassive black hole of a galaxy eat something, either a planet or a brown dwarf.

9:24 am

Astronomers watch the central supermassive black hole of a galaxy eat something, either a planet or a brown dwarf.

Astronomers were using Integral to study a different galaxy when they noticed a bright X-ray flare coming from another location in the same wide field-of-view. Using XMM-Newton, the origin was confirmed as NGC 4845, a galaxy never before detected at high energies. Along with Swift and MAXI, the emission was traced from its maximum in January 2011, when the galaxy brightened by a factor of a thousand, and then as it subsided over the course of the year. “The observation was completely unexpected, from a galaxy that has been quiet for at least 20–30 years,” says Marek Nikolajuk of the University of Bialystok, Poland, lead author of the paper in Astronomy & Astrophysics.

By analysing the characteristics of the flare, the astronomers could determine that the emission came from a halo of material around the galaxy’s central black hole as it tore apart and fed on an object of 14–30 Jupiter masses. This size range corresponds to brown dwarfs, substellar objects that are not massive enough to fuse hydrogen in their core and ignite as stars. However, the authors note that it could have had an even lower mass, just a few times that of Jupiter, placing it in the range of gas-giant planets.

All the instruments listed above are orbiting space telescopes. You can read the science paper here.

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James Hansen is retiring from NASA and will dedicate his time to global warming activism.

5:26 pm

James Hansen is retiring from NASA and will dedicate his time to global warming activism.

All that is really changing is that Hansen will no longer work for the government. The activism has been going on for a very long time.

Also, it is interesting how this New York Times article seems very unaware of this fact, which makes all of Hansen’s global warming claims very suspect. Might the Times not want the public to know this annoying detail?

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“The fact that global surface temperatures have not followed the expected global warming pattern is now widely accepted.”

10:38 am

The uncertainty of science: “The fact that global surface temperatures have not followed the expected global warming pattern is now widely accepted.”

This quote above refers to scientists in the climate field, who are now admitting that for the past 20 years the climate has shown no warming, despite the continuing increase in CO2 in the atmosphere and their computer models that all predicted increased temperatures because of that CO2.

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Science and sequestration in context

11:00 am

On March 21, the House accepted the continuing resolution proposed by the Senate for the year 2013. This continuing resolution will fund everything in the federal government though September of this year, and includes the cuts imposed on March 1 by sequestration.

As it always does, the journal Science did a specific analysis of the science portion of this budget bill. As usual, they looked only at the trees, not the forest, comparing the budget changes up or down for the 2012 and 2013 years only, noting how those changes will impact each agency’s programs. As usual, Science also took the side for more federal spending, assuming that in each case any cut was sure to cause significant harm to the nation’s ability to do cutting edge science.

I like to take a wider and deeper view. Below is a chart showing how the budgets for these agencies have changed since 2008. They give a much clearer perspective of the consequences of sequestration and the cuts, if any, imposed by Congress on these science agencies.
» Read more

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