++Carnival of Space

Here’s your weekly astronomy and space science fix at Carnival of Space #61. I could not get my sh*t together this week but I’m hoping to contribute to future carnivals. Weekly is a daunting thing for slackers.

Go read up and tell us what you think!

Slacker wins award

Slacker Astronomy founder and Tufts grad student Aaron Price has won a Chambliss Astronomy Achievement Student Award for his poster on BZ UMa.

I stopped by Aaron’s poster at AAS in St. Louis and he explained the work he presented while I grabbed it on video.

Here you go — enjoy!

Aaron Price on BZ UMa [FF] (MP4 video, 30.3MB, 04:10)

Carnival of Space No. 60

Hear ye, hear ye! Assembled here is the official Carnival of Space No. 60 wherein the written assemblage of the musings of many eminent natural philosophers are here provided for your amusement and betterment.

In order of receipt by yours truly and in the own very words of the author, notwithstanding some minor editorial discretion, here, then, are the proceedings:

From Slacker Astronomy:

Hi Michael,

Here you go - hot off the keyboard!

Regulus - Just when you think you know a star

Cheers,
Doug

From astroENGINE:

Hi Fraser,

My entry:
Title: “No Doomsday in 2012: The Reason Why Science Will Not Win”

Just a brief discussion about the recent 2012 articles and why science is fighting a loosing battle against the scaremongers

Cheers, Ian

From 21st Century Waves:

Hi Fraser,
Here’s a post: State of the Wave, Friday 6/20/08

I hereby officially volunteer to host the Carnival.

Best regards…
Bruce Cordell

From Centauri Dreams:

Hi Fraser,

I’ll send “Alpha Centauri and the Long Haul“:

This one is a look at projects in human history that have involved lengthy time spans, with relation to interstellar concepts like the Ultimate Project, a multi-generational starship that might take 10,000 years to reach its destination. The idea of long-term thinking in a short-term culture is explored.

All best,

Paul

From Music of the Spheres:

GeoEye-1 and TMA Notes

Music of the Spheres looks at the soon-to-launch commercial Earth-imaging satellite GeoEye-1 and at some details of its high-resolution optics.

From Free Space:

humm …

how ’bout this for this week: Metaphysically Speaking

Congress may force NASA to fly a canceled dark matter experiment, but it’ll have to be without a rescue shuttle available.

Thanks!

Irene

From Start With A Bang!:

The Moon looks huge!!
Because who doesn’t love the moon, really?

From Space Feeds:

This week’s space video of the week is the 1997 sci-fi/fantasy film The Fifth Element.

Space Video of the Day - 080623

Ed

From Nextbigfuture:

Article Title: The Space elevator games and the lunar lander contest preview for 2008

Summary: The Space elevator power beaming (climber) competition is on Sept 27, 2008 and the lunar lander contest is Oct 24, 25 2008. The main focus is on the space elevator climber teams and the progress towards a tether.

Brian Wang

From Orbiting Frog:

Fraser,

Crikey, the sixtieth must be coming up!

My entry this week would have to be the ‘Font Sizes of the Planets‘

Thanks,
Rob

From Cumbrian Sky:

Hi,

I’d like to submit this Blog post for your consideration for this week’s Carnival, please.

Title of Post: “The future’s not orange, it’s ICY…”

Summary: As exciting and important as it was, contrary to what many media reports have claimed, Phoenix’s spotting of ice on Mars wasn’t actually a “discovery” - ice had been seen on Mars by other probes over the years. But while the celebrations got into full swing in Arizona, NASA quietly released another “icy image” that received almost no attention at all, yet illustrated something possibly even more profound, giving us a tantalising glimpse into the future of space exploration and Mankind…

Stuart Atkinson

From Dynamics of Cats:

Holy Vanishing Crumbs, Phoenix!
yet another entry on Phoenix lander stuff

From A Babe in the Universe:

Aloha Carnival!
Endeavour returned to Earth June 14 with some spectacular photos from the Space Station.
“Photos From STS-124”

Mission STS-124 successfully installed the Japanese Kibo module. Human figures work on the Station in the ultimate high-rise project. We see the Shuttle docked at the Station, and a view of a place an earlier Endeavour once charted.

Thank you for hosting this week’s Carnival.
LOUISE RIOFRIO

From: Tyler at The Planetary Society:

Hi there,
Here’s my latest astronomy blog posting for the Carnival of Space.

Stop 14: Bryce Canyon National Park, Utah

This one talks about light pollution and astronomy outreach within the national parks.

Cheers,
Tyler

From the weblog of Columbus State University’s Coca-Cola Space Science Center:

Would you like to swing ’round a star?

Thanks!
– Rosa Williams

From Jeff Gortatowsky:

Star Party season…Or also know as fire season here in California. However being optimistic, it is star party season in the northern hemisphere. Coming up next week are two big star parties in northern California. The Golden State Star Party (GSSP) and the Shingletown Star Party (SSP). Both are held in an area that is one of of the darkest yet still accessible areas of the state. GSSP is currently booked up. SSP however still has room and day/night passes are available at the gate.

(Editor’s Note: It appears that SSP is “postponed until at least the end of August 2008″, according to their web site.)

From Astroblog:

G’Day

Title of Post: The Odyssey and the Celestial Clock

Brief summary: Has the date of homers Odyssey been found using the patterns of planets in the sky?

Cheers! Ian

From Emily Lakdawalla at The Planetary Society Weblog:

Hi there,

This week I’ll change things up and suggest you link to my weekly “What’s up” post, highlighting the current activities of all 20 of the active planetary space probes in and beyond the solar system. For the curious, that list includes: MESSENGER, Venus Express, Chang’e 1, Kaguya, Spirit, Opportunity, Phoenix, 2001 Mars Odyssey, Mars Express, Mars Reconnaissance Orbiter, Rosetta, Stardust, Dawn, Deep Impact, Hayabusa, Genesis, Cassini, New Horizons, and Voyager 1 and 2.

Happy Mars solstice! (And Earth, too.)

What’s up in the solar system for the week of June 23

–Emily

From Catholic Sensibility:

Hi Fraser,

If it’s not too late, here’s my entry for the carnival:

Satellite Imagination 1.6: Meet The Louisians

Cheers to all at UT

Todd

From goodSchist:

Hopefully this isn’t too late:

The importance of being Ivuna

Cheers,
-Chris

From Twisted Physics

This is a neat one with great discussion - Sean Caroll over at Cosmic Variance vetted the scientific points Jennifer discusses:

Devourer of Worlds

Best,
~Dave

From Beth Katz:

Hanny’s Voorwerp is an intriguing green blob that looks very much like “The Incredible Hulk”. You, too, can explore the Galaxy Zoo.

A little closer to home, aurora watchers have been forlornly hoping that the sun will get past its solar minimum and get some sunspots. In January 2008, NASA reported that Solar Cycle 24 had started. It seems that there has been little activity since then unless you count Tiny Tims. But the STEREO spacecraft caught stereo images of twisting solar jets. Those spacecraft have some amazing images. Maybe by the time the Solar Cycle 24 Conference rolls around in December we’ll see a few more spots.

Too many clouds? Test your knowledge of lunar phases with the lunar cycle matching phase game or these lunar phase activities.

UPDATE Oh noes! I forgot one!

Did I break some rule or offend the Gods?

I sent a blog to Fraser and one to you. You said you’d pick.
Did they both suck or what?

–
Mike Simonsen
Development Director
American Association of Variable Star Observers
www.aavso.org

So…

From Simostronomy:

Hey Michael,

You may have received an entry for me for the carnival, but you might consider this one in its place.

What Are Variable Stars?

–
Mike Simonsen
Development Director
American Association of Variable Star Observers
www.aavso.org

Many thanks to the hard work and good thinking of our submitters. It’s a lot of great reading for us to digest. I’ve never hosted a carnival before so I probably did it wrong. Please be kind to my mistakes. Authors, let me know if I made any errors or omissions with your submission and I will promptly correct.

Wanna join the Carnival of Space? Just send the URL of your entry via electronic Internet email message to carnivalofspace@gmail.com.

Cheers, beers and clear skies,
Michael

Regulus - Just when you think you know a star

Looking out at the night sky, it is easy to believe that we’ve learned everything there is to know about the brightest stars. Fortunately, they keep surprising us! A delightful paper has just appeared on the astro-ph preprint server which combines many elements of a great story.

Regulus is the 22nd brightest star in the sky to the naked-eye. Since it lies along the path followed by the Sun, Moon and planets (called the “ecliptic”), bright planets frequently pass close to the line of sight to this majestic star. In fact, it is so close to the ecliptic that the Sun passes within a half degree of it every August. (Don’t go looking for this event visually! If you want to see how close, check out the movie from the SOHO satellite here. The brightest object - besides the Sun! - is Saturn. Regulus pops out from behind the occulting disk right at the end of the MPEG.)

I first became more closely acquainted with Regulus during my postdoctoral fellowship at the Dominion Astrophysical Observatory in Victoria, British Columbia (Canada). I would frequently use the 1.2m telescope with its fantastic high-resolution spectrograph. One of the shortcomings of filament bulbs is that there is precious little light emitted at the blue end of the spectrum - if you want to calibrate the pixel-to-pixel sensitivity of your detector, you can’t get enough blue signal without saturating the red end. What to do, what to do … One fine solution is to observe a bright blue star which is rotating so quickly that all of its spectral lines are smeared out over many, many pixels. Enter Regulus! The few spectral lines in its spectrum were already broad hydrogen lines and the rotation rate of over 300 km/sec smeared them out even more. A great star for calibration.

And a very poor one for measuring the line-of-sight (”radial”) velocity using the Doppler shift! In fact, astronomers last studied it for binarity in 1912-1913 - almost a century ago! Many hot stars are far enough away that lines from interstellar gas can be used as reference points for radial velocities. Not so Regulus - it is only 24 parsecs away and there just isn’t enough gas along the line-of-sight to this neighbor of the Sun.

Regulus came back into favor when its shape and the brightness distribution could be measured by a very cool kind of optical instrument called an interferometer. Work by McAlister and collaborators using the CHARA long-baseline optical inteferometer they created on Mount Wilson found that Regulus is rotationally-flattened and it spinning at 86% of the speed at which the surface gas would cease to be bound to the star. They were able to show that it was darker along the equator of the star, too. This high rotation rate was an anomaly for a star that was as old as Regulus (apparently 150 million years - pretty old for a star of this mass) since similar stars seemed to be fast rotators only early in their lifetimes.

So Doug Gies and his collaborators embarked on a new study using modern instrumentation to see if there was any evidence of it orbiting the center-of-mass of a binary system containing it and a hitherto-unknown companion. As a bright star, there was plenty of light available to be dispersed by high-resolution spectrographs. They used several in their study including two “unusual ones” - the Kitt Peak National Observatory Coude Feed Telescope and the Multiple-Telescope Telescope!

Let me briefly describe these two instruments. A Coude room is very high-resolution spectrograph capable of tearing the light from a telescope into very fine shreds of color. It was designed to be “fed” by the 2.1m telescope at Kitt Peak. However, observatories tend to do deep imaging around the time of New Moon (i.e. when the sky is dark) and the 2.1m served a variety of such needs. It was realized that the a smaller telescope could “feed” the spectrograph during these periods and that brighter stars could be observed with that smaller telescope plus Coude spectrograph while the big telescope was busy imaging!

The Multiple-Telescope Telescope at Hard Labor Creek in Georgia is another ingenious system for bright star spectroscopy. It has nine relatively inexpensive 0.33m mirrors which focus onto nine optical fibers which then feed a stable, bench spectrograph. Since it only studies bright stars, the mirror pointings can each be individually-tweaked to center up on the bright star. It uses a cheap alt-azimuth mount and collects as much useful light as a 1.0 telescope for a tiny fraction of the cost of such a large telescope.

So - you are asking - what did Doug Gies and his collaborators find? They found that Regulus was indeed a spectroscopic binary. Once every 40.11 days, the system completes one orbit. Regulus itself has a mass of about 3.4 times that of the Sun. The companion of Regulus is much less massive - only about 0.30 solar masses. Such a small mass object is either a low-mass star or a white dwarf. The latter possibility provides an explanation for Regulus’ rapid rotation! The idea is that the companion was once the more massive member of the pair and when it finished hydrogen burning in its core, it expanded dramatically and started losing mass to Regulus in a manner which “spun it up”. A mass of 0.30 solar masses is very low for a white dwarf - such objects are found only in systems where it is clear that much mass has been transferred.

A final piece of the puzzle fell into place when spectra taken using the far-ultraviolet Spanish satellite MINISAT-01 were re-examined. When the expected contribution from Regulus was removed, light remained in the ultraviolet region of interest - consistent with a white dwarf but not a cool low-mass star. So Regulus joins the list of bright stars in the sky (which includes Sirius and Procyon) having white dwarf companions and proves once again that “three out of every two stars is a binary”!

Their paper has been accepted for publication in the prestigious Astrophysical Journal Letters.

A Spectroscopic Orbit for Regulus
Doug Gies (GSU) et al

Space Out

Hey, bloggers, writers and astronomy/space enthusiasts! We’re hosting the next Carnival of Space right here at Slacker Astronomy. Here’s Fraser’s standard blurb:

If you’ve got a space-related blog, you should really join the carnival. Just email an entry to carnivalofspace@gmail.com, and the next host will link to it. It will help get awareness out there about your writing, help you meet others in the space community - and community is what blogging is all about.

Get thee to thy keyboard and get insightful on our asses! We need your awesomeness in our greedy little hands before June 26th, 2008.

Interview: Juan Collar and Detecting Dark Matter

We bring you another fascinating cosmology interview with a genius over at the Kavli Institute for Cosmological Physics. This time we speak to Juan Collar, a name that I am, apparently, incapable of saying. He leads a group at Kavli which is pursuing several experimental approaches to detecting dark matter in the lab.

Interview: Juan Collar and Detecting Dark Matter (MP3, 28.3MB, 41:10, Show Notes)

Interview: Susana Deustua of the IYA

Here is a short interview with Susana Deustua of the Space Telescope Science Institute about the International Year of Astronomy, with a brief cameo by Mike Simonson of the AAVSO. I caught them at the opening reception of the American Astronomical Society meeting in St. Louis.

Interview: Susana Deustua of the IYA (MP4, 15.8MB, 2:11)

Not Ad Supported

I don’t know if you noticed that Slacker Astronomy does not have advertising. We did have a sponsor or two in the early days. But the web site is entirely devoid of ads and we do no advertising in the more recent podcasts.

What do you think of this?

We are entering a new age of Slacker Astronomy where we want to have the resources to travel and have support for acquiring the technology necessary to make interviews and other podcasts possible.

There are 2 main choices for this, that I know of:

1. Accept advertising
2. Solicit donations from listeners
3. All of the above

The only other possibility I can think of is a kinder, gentler version of #1 as is done by NPR and the like.

I think experience has shown that #2 is a hard nut to crack. People will show occasional financial support some of the time, but in terms of having on on-going revenue stream to support operations, everyone I know who makes money makes it via #1.

Which I think is both good and bad. The bad is web sites and RSS feeds which are littered with advertising. On some sites it is literally hard to find the content among the ads. Ads are annoying and advertisers getting more annoying all the time.

The good news is — I’m as reluctant to write checks as you are! If Meade or Swinburne can foot the bill, it makes it easier, in a way, for everyone. Most advertisers in the science/astronomy world are pretty good so you usually aren’t presented annoying, distasteful ads.

The bottom line for everyone doing podcasting and video podcasting is that you can achieve more with more resources at your disposal. So to the extent we want to do more and should do more, a little funding becomes important.

So brace yourself, I guess, for one of the above! We do want to do more with Slacker Astronomy so we will be thinking of ways to increase the resources at our disposal.

Chris Lintott

I had heard of Chris Lintott but I didn’t really know why. It turns out he is an astronomical celebrity in the UK due to his work on The Sky At Night. He is also one of the main people behind the very clever crowdsourcing project called Galaxy Zoo.

To the right is a photo of Chris and I at the AAS Meeting in St. Louis where we co-presented on several IYA New Media discussions and panels. We also drank a little too much one evening but on that subject I will say no more…

Simostronomy: An astronomy blog is born

Mike Simonson is a friend of mine and he is the creator of CVnet, a web site and email list that discusses cataclysmic variable stars. He’s also an avid amateur observer and has been a great supporter of the AAVSO. In fact, he was recently hired by the AAVSO to help build the organization.

He was in Saint Louis and we had a lot of laughs. Apparently hanging out with me, Aaron, Phil, Pamela and Chris was infectious because Mike got home and started a blog: Simostronomy. Check it out!