astro
catdynamics | October 22, 2009"Seeking a Human Spaceflight Program Worthy of a Great Nation"
Review of U.S. Human Spaceflight Plans Committee
The Augustine Report on Human Spaceflight is out: all 157 pages of it (pdf), with press conference starting at 1 pm today.
As you know, Bob, the committee, chaired by Augustine of the Augustine Report, and a list of impressive members (and, as you know, the output of a committee can to some extent be determined by the choice of membership...), had a mission to sort out the unsustainable and vague ambitions for human exploration in space that was the legacy of the last 20 years of…
catdynamics | October 20, 2009So, I was thinking, where are the cold alien intelligences who ought to be out there, studying us dispassionately, as if we were microbes...?
Well, what if we accidentally killed them all?
No, really.
See there has been this flap about the LHC destroying the universe....
Now, it could happen, like if it actually made a Higgs and triggered a vacuum phase transition or something (yeah, blah blah - ultra-high energy cosmic rays hitting the moon ought to have c-o-m collision energies comparable to LHC collision energies, even given the GZK cutoff, so why hasn't that destroyed the universe, eh?…
catdynamics | October 14, 2009There have been a lot of rather belated reports of the LHC failing due to acausal physics.
This is clearly nonsense.
We have known for a long time that it is most likely due to anthropic selection within a many worlds universe.
This is serious.
catdynamics | October 13, 2009Continuing our inadvertent theme of "alternative physics", we contemplate whether the Force really is with us, and find the fundamental mass scale for MOND...
Earlier, we had a nice little discussion about the persistent fringe phenomenon of one of the alternative models for gravity that persistently bob up in astrophysics...
Specifically MOND.
Now, the details of MOND are kinda irrelevant, what is a key point is that MOND provides a phenomenological argument for a fundamental acceleration scale, a0 ~ 10-10 m s-2.
Whether this is really "fundamental" is disputable, and at some level…
catdynamics | October 9, 2009"There is no use trying; one can't believe impossible things."
"I dare say you haven't had much practice. When I was your age, I always did it for half an hour a day. Why, sometimes I've believed as many as six impossible things before breakfast."
This week, a short, innocuous little astrophysics paper appeared in Nature discussing the apparent inferred constant surface density of cold dark matter in the inner part of galaxies.
This somewhat startled fellow SciBling Ethan, enough for him to bang out a new post - discussing why cold dark matter is to be preferred to an alternative model…
catdynamics | October 8, 2009Obama and friends: Celebrating the Year of Astronomy in Style.
Obama Star Party!
With Bonus Real Stars.
"The President and First Lady host NASA astronauts, area middle schoolers, and innovators in the field of astronomy for a night of fun, learning, and stargazing on the South Lawn. October 7, 2009."
John Grunsfeld setting up the telescopes.
Ok, that might work...
Hope they turned those bloody lights down though...
click to embiggen - from Celestron Images
ε Lyrae - what Obama saw
Brought in two teen amateur astronomers - Caroline Moore, supernova hunter; and Maura's student from Green…
catdynamics | October 6, 2009Nobel Prize in Physics, in case you hadn't heard, went to Kao for Fiber Optics and Boyle and Smith for developing the fundamental CCD technology.
Some people, naming no names, seem a little unhappy about this.
Well, ol' Alfred had his purpose when he endowed the Nobel Foundation with his ill gotten gains, and such things are somewhat binding.
Further, pushing the Swedish Academy on these things, to do the "right thing" and give the Prize to one of your pet subfields, however more "fundamental" it may be, tends to backfire.
Think of the Academy as a very proper and very small club, about…
catdynamics | September 25, 2009NASA sees water everywhere it looks! In surprising places.
With pictures.
But maybe not where you heard...
No, not the Moon, as interesting and useful it might be.
This is the other gorgeous water discovery, this thursday...
Yes, there is water on Mars, again.
This is actually a very nice result.
Although the timing of the announcement, hard on the heels of the quantitative measuring of OH on the lunar surface is opportune indeed.
MRO has seen small fresh meteorite craters Mars - with depths of 1-3 meters.
fresh crater cluster on Mars, from a year ago - dark splodges on right (click to…
catdynamics | September 18, 2009For over 20 years, the binary star DI Herculis has been measured to have anomalous precession, inconsistent with the predictions of general relativity, in the limit of two spherical masses orbiting with the measured orbital parameters.
So, either there were some other classical torques in the system, or general relativity was wrong.
DI Herculis is a close B star binary, with 10 day orbital period and eccentricity of ~0.5, that is orbiting near edge-on to our line of sight, and thus the stars eclipse each other.
The stars are hot and massive - 5.15 and 4.52 solar masses respectively, with…
catdynamics | September 17, 2009Swift does a large field mosaic image in the ultraviolet of M31
Ok, so Astronomy Picture of the Day beat me to this...
Andromeda in optical (click to embiggen)
Swift took a 330 picture mosaic of our nearest respectably sized neighbour galaxy, the venerable, and naked eye Andromeda, aka M31. They used the itsy bitsy little Ulvtravioler/Optical telescope on board, which has surprisingly decent UV capability.
Andromeda - ultraviolet mosaic (click to embiggen)
Very, very nice.
Go to apod to get the nice gif flick between the UV and optical images.
The UV images preferentially trace young…
catdynamics | September 17, 2009HD61005 is a nice normal, young star with a dusty disk that will likely make planets one day. Real soon now in fact.
But HD61005, like some other stars, is different.
It is warped.
Well, the rim of its disk is.
Warped disk of HD61005 (click to embiggen)
The above picture is a Hubble image with the light from the central star suppressed, showing the extended disk of dust around the star.
As you can plainly see, the disk around the star is bent.
Question is why?
We've seen warped disks around stars, and often there is an apparent reason, such as radiation pressure from another, massive and…
catdynamics | September 12, 2009NuStar is a small explorer class hard x-ray focusing telescope.
It is now scheduled for launch in august 2011.
NuStar is optimised for the hard x-ray range, looking at energies from 6 keV to 79 keV, with energy resolution of ~ 1 keV and, sub-arcmin angular resolution ( Prof. F. Harrison PI).
The telescope does narrow field x-ray imaging in the spectral range beyond that covered by Chandra and XMM-Newton.
Previous imaging telescopes in the hard x-rays used coded aperture masks, but NuStar uses grazing incidence focusing optics on a 10 meter deployable boom.
The satellite is due to be…
catdynamics | September 11, 2009Hubble post-refurbishment engineering and early science images were released on wednesday.
Go check them out.
Here is the press release and image link
sorry this is late, I'm on a field trip in the middle of somewhere...
Showcases Wide Field Camera 3 very nicely!
All the images are here - there are a LOT of images and spectra
Everything from Jupiter post-impact to distant Quasar spectra.
catdynamics | September 9, 2009Our astrobiology graduate seminar has started, and last week it got interesting as we pondered "weird life".
I'm a co-PI of the Penn State Astrobiology Research Center, and as part of our program we run an Astrobiology graduate seminar, which is generally topic based.
This year it is more student oriented, but occasionally the faculty are invited to kibitz.
Last week the theme was "Weird Life" - we fling this at all groups of students we can gather in astrobiology, in the hope that someone will eventually have a flash of insight.
The essential topic is: "if there is life out there that is…
catdynamics | September 8, 2009Ok, here we go again... someone thinks it is funny to compare economics with astronomy...
Worse, than that, it is Chad hisself, hovering near one of the antipodes of the blogosphere.
It was of course Krugman who started it, but Sean had to go stir it up, didn't he?
Then Dave's got to go Pontificate and all, so how can I not?
Why, some of my best friends are economists...
So, is economics really like astronomy?
No!
Well, except for our mutual affinity for unreasonably large numbers, mesoscale problems and models that are mostly too messy to actually solve for realistic situations.…
catdynamics | September 8, 2009Augustine Panel delivered its report and recommendations to Obama today.
This is important, it will set the menu of options for Obama to choose NASA's future, and a decision needs to be made, and soon.
Almost none of the options are good.
The basic problem is that NASA "Exploration" - the human spaceflight component, does not have enough funding in the projected budget to do what needs to be done - it can't run ISS, and the Space Shuttle while developing new launchers and hardware for new Exploration goals.
This is underfunding that goes back to Nixon, but has been most acute in the last 3-4…
catdynamics | August 27, 2009The Photomixers are back, inspired by the Great Jupiter Impact of 2009 they reminisce in style.
catdynamics | August 19, 2009Interesting new paper coming out in Nature this week, presenting early scientific results from LIGO on the amplitude of stochastic gravitational radiation background of cosmological origin.
LIGO went into science operation a few years ago, achieving phase I design sensitivity at the end of that set of operation, the S5 science run from Nov 5th 2005 till Sep 30th 2007. During that time a year of coincident operation at the Hanford and Livingston interferometers was achieved, and the results of this data set are coming out.
LIGO Hanford (click to embiggen)
LIGO shut down for interim…
catdynamics | August 13, 2009never mind h'
it is the second derivative we like...
yes, I know it is pathetic, I got nothing
Unfortunately I know exactly what made me think of this.
Curse you C. Ford!
'though associating "Hair Cut 100" with the whole process is wholesome in a strange sort of way.
Ay ah ah ah ah ah