Category: Cosmos

Carnival of Space Week #72

The Carnival of Space Week 72 is up and running. Informative stuff.

Also informative is this little gem… Space Elevator: Physical Principles …which covers the derivations and consequences of the main physical aspects of a basic space elevator. Written by Ranko Artukovi? of Zadar, Croatia, and definitely worthwhile for all hard-core applied maths freaks and space-nuts.

From impeccable mathematical applied-physics to dubious applied physics we have Brian Wang’s latest on the EM-Drive… Superconducting Radio-Frequency Cavities for High Q …the table he gives makes me rather dubious about the EM-Drive’s utility.

Effect of increased Q for the Emdrive

  • Q=50,000 (1st gen.) Static thrust=315 mN/kW Specific thrust at 3km/s=200mN/kW
  • Q=6,800,000 (supercond) Static thrust=42.8 N/kW Specific thrust at ??km/s=??N/kW
  • Q=5×10^9 (supercond) Static thrust=31.5 kN/kW Specific thrust at 0.1km/s=8.8N/kW
  • Q=10^11 (supercond) Static thrust=630 kN/kW Specific thrust at 0.1km/s=??N/kW

    • “Q” appears to be the number of reflections within the microwave cavity before the wave is absorbed. So while the static thrust of a high Q cavity is very high it very rapidly loses thrust as speed increases, so much so that to levitate with such a drive seems rather unstable. It would be an incredible thing, if true, but the EM-Drive is yet to be demonstrated in free-fall. That will prove whether it really does convert EM energy directly into kinetic energy. By my rough figuring the first quoted figure above indicates that the EM-Drive is turning EM energy into KE at 60% efficiency at 3 km/s. Not bad.

Slo-Mo Earth, Virtual Geology and Creationist Weirdness

Creationism, of the recent variety, has some odd variations which can, arguably, be compatible with straight science teaching. Firstly, there’s the new view in “Creation Ministries International” (the rebadged “Answers in Genesis”) that God slowed Earth, and maybe the Solar System’s, apparent time down so that the light from distant stars had real time to travel to Earth from billions of light-years away. John Hartnett, the propagator of this new idea, is a trained physicist with a penchant for weird cosmology – he’s a fan of the work of astronomer Harlton Arp, who is notorious for odd ideas about quasars being “proto-galaxies” spat from nearer regular galaxies. Thus all the evidence for an ‘old’ Universe is real, but isn’t real for planet Earth.

His cosmology presented…
A New Cosmology

Some of his papers… arXiv.org Search on John Gideon Hartnett

Unfortunately for CMI and Hartnett the evidence for age written in lakebed sediments and cosmic-ray traces in rocks and trees, is undeniably much greater than the 6,000 years of post-Edenic time attested in Scripture. The adamantine nature of this data led the Institute for Creation Science’s radiometric dating expert, Gerald Aardsma, to leave the ICR under rather acrimonious circumstances – bad for business I guess. But Aardsma didn’t lose faith in those 6,000 years – he found an extra 1,000 in the Bible, and became “The Biblical Chronologist” with a wholly different take on geology’s pesky timeclocks.

Basically Aardsma proposes that geological and prehistoric time is “virtual time”… what could he mean? Here’s a FAQ answer…

Virtual history is not a hard idea. Just think about what it means to actually CREATE something. Creating a story is a helpful analogy. Take “The Hobbit” as an example of a created entity. Now step into the book with Bilbo on page one and begin to examine the world around you. Everything you see and examine around you has already, on page one, an extensive built-in virtual history. Bilbo is in his 50’s as I recall. So he has a virtual history. His house has been dug back into the hill, implying someone did some digging. If you examine the tunnels you can no doubt find tool marks left by the workmen. His front door is made of wood, implying trees grown, sawn into planks, planed, and fastened together by craftsmen, all before the story begins. And on and on it goes…Bilbo’s clothing with all those stitches, and the soil in his yard and garden with humus from long-dead leaves, …

We are living in a CREATION. The creation we are living in is a story of God’s making. It opens on page one 5176+/-26 B.C. (by my best reckoning so far). The story moves from Creation to Fall to Flood to Exodus to Birth of Christ to Crucifixion to Redemption to ultimate Restoration of all things. This story is our reality, but it is not ultimate reality. (God is ultimate reality—He transcends the story just as any author transcends their created story.) And like any story, it has, necessarily, a virtual history built in from page one onward.

The big take-home point is that evidence of virtual history—of even millions or billions of years of this or that process operating in the past—does not and cannot falsify the fact of creation in a created entity. So we can let the virtual history data about the Grand Canyon or the ice ages or whatever else speak for itself and say whatever it seems to say. We do not have to resort to foolishness (e.g., denying the validity of tree-ring calibrated radiocarbon dates) to try to wipe out every trace of any natural process prior to the biblical date of Creation. We understand virtual history to be part and parcel of any created thing, so evidences of such processes do not threaten our faith or falsify the Bible’s claim that we got here by supernatural creation just over 7000 years ago.

Sincerely,
Dr. Aardsma

From here… Virtual History

So do we believe our senses or a certain interpretation of the Bible?

First Images of Asteroid Steins from Rosetta

The ESA pulled off its first asteroid flyby on the Rosetta comet-probe mission…

Steins: A diamond in the sky

…after an Earth gravity-assist maneuver, 13 November 2009, another asteroid, 21 Lutetia, is due for a flyby July 10, 2010, and the target comet, 69P/ Churyumov-Gerasimenko, will be reached in c. May 2014. The HST has taken “close ups” of the target comet, revealing a nucleus somewhat larger than the original target, Comet Wirtanen, but the comet lander should be up to the task just fine. There are also computed images images of 21 Lutetia from its lightcurve… Thirty Main Belt asteroids from their lightcurves …though such guesstimates should be taken with a grain of salt.

Carnival of Space: Week #68 …star-travel won’t be easy

Welcome to the Carnival of Space, brought to you this week by Crowlspace and the never-tiring efforts of Fraser Cain and Universe Today. First cab off the rank is musings by Paul Gilster (Centauri Dreams) who ponders the difficulty of interstellar travel as depicted by Robert Frisbee who brings us the 160 million ton antimatter powered starship (see this old “Discover” magazine piece Star Trek for more details.) “Crowlspace” also covers Frisbee’s rather gloomy prognostications here… Antimatter Ain’t What it Used to Be

Also on theme Brian Wang’s Next Big Future gives another viewpoint on the difficulty of antimatter rocketry and the relative ease of leaving the engines at home and riding a beam… Interstellar Prospects

Next Nancy Houser of A Mars Odyssey ponders the dangerously variable magnetic field of the Earth… A Newly Found Dent in Earth’s Protective Bubble…. Dr.Ian O’Neill puzzles over the folly of media hyping of a radio detection of the Galactic Core… No, An Alien Radio Signal Has Not Been Detected.

The Bad Astronomer blogs at “Discover” magazine on why telescopes haven’t been used to disprove the “Moon Hoax” claims… Moon hoax: why not use telescopes to look at the landers? (as if astronomers don’t have better things to look at anyway!)

Dr. Bruce Cordell of 21st Century Waves draws on the the Lewis and Clark expedition (almost as arduous as a trip to Mars) to get perspective on current space exploration hopes… 10 Lessons Lewis & Clark Teach Us About the Human Future in Space.

From Out of the Cradle just in time for back to school (in the Northern Hemisphere that is), Ken Murphy reviews the new ‘Kids to Space Mission Plans’ designed for teachers and homeschoolers who want to add some space-themed activities to their classrooms… Take an Educational Field Trip to the Solar System. Wish I’d had that 6 months ago 😉

Darnell Clayton’s Colony Worlds poses a pungent conundrum for interplanetary colonisation… Living Off World May Stink … our dreams of humanity expanding throughout our native star system may ultimately come to naught, due to the simple fact that living off world may irritate one of our key bodily members, also known as the nose.

This week David Portree’s Altair VI promotes a new facility for public and professional researchers he’s just opened at the US Geological Survey Flagstaff Science Center:

We Have Liftoff

He also looks at a novel approach to Mars sample collection put forward by Alan Stern in 1989.

Mars Tethered Sample Return (1989)

Ray Villard’s Cosmic Ray asks if arguing over Pluto’s status as a “real” planet is worth the hype… Spirited Pluto Battle, But a Great Debate? Once upon a time there were only 7, including the Sun and Moon. How things change!

OTOH Emily Lakdawalla argues maybe anything studied by “Planetary Scientists” should be called a “planet”… Things that probably won’t ever be called planets, but maybe they should

Simostronomy (Mike Simonsen) looks closer at the good news and the bad news out of a recent cosmogony simulation… Planets – Good News, Bad News …which found only 1 solar system like ours out of 100 simulations. Terrestrial planets form easily it seems, but not in solar systems like our Solar System.

New & Noteworthy at the LPI Library gives us an update on recently available Astrophysics related resources, including the new Portal to the Universe.

The Phoenix Mars Polar Lander spied frost for the first time this week… Phoenix Sees First Frost …courtesy of The Meridiani Journal.

Ian Musgrave, the Astroblogger says Kopf Hoch! Raise your heads people and Look! I did and I saw Venus and Mercury together at sunset yesterday.

Stuart Atkinson, of Cumbrian Sky gives us… Narnia Mars

Bruce Irving’s Music of the Spheres looks back on the Earth from deep space… Distant Mirrors (and Cribsheets)

Aloha Carnival! Says A Babe in the Universe, Louise Riofrio. Last week the Cassini spacecraft made a close flyby of Saturn’s mysterious moon Enceladus: Enceladus Flyby …Cassini was able to localise sources of the water geysers erupting from the South Pole. More heat comes from this little moon than can be produced by tidal
forces or radioactive decay. Louise speculates about other causes, even a Black Hole.

And that’s it for this week! Enjoy, be enlightened and (if you’re in the USA) vote for the right person to lead the Spacewards Vanguard… whoever that might be 😉

The New Milky Way

The latest view of our Galaxy, the Milky Way, can be found at the Spitzer Infra-Red Space Telescope’s newspages here…

The New Galaxy

…seems we’re now officially a few galactic arms short – two arms based on old hydrogen-based maps aren’t evidenced by actual star-counts and thus were an artefact of the limitations of hydrogen-based radio astronomy. The Galaxy is still a BIG place, but it looks more like a pretty barred spiral galaxy than a relatively dull “grand-design” flocculent spiral like it did in the old maps.

But why are spiral arms the way they are? It’s a puzzle, but one astrophysicists have no end of good ideas about – and then along come some new surprises, like this one…

Black Hole Mass determines tightness of the Spiral

…seems the heftier the central Black Hole, the tighter the spiral arms. In our Local Group there are three big Spirals – ours, M31 (in Andromeda) and M33 (in Triangulum) – and the central Black Hole masses 4 million Solar masses (for the Milky Way), 180 million for M31, and just 1,500 for M33. M33 is a pretty loose spiral, though pretty. Andromeda’s M31 is tightly wound, from what we can see as M31 is tilted away from us. SO the Milky Way is somewhere between the two.

But why the correlation? Dark Matter? Weird gravity lanes? Something in hyperspace? Who knows? And that’s why astronomy is both fun and worth doing…