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Holes around rocks

ESP_037201_2450_0.589xA piece of Mars: This scene (509×382 m, or 1670×1253 ft), aside from showing some lovely rippled dunes, has many car-sized boulders in it. Some are surrounded by ditches in the sand, like little moats. Why? The sand is blown away from the ground as wind impacts the rocks. My colleague Mark Bishop has studied these in more detail (read more here) (HiRISE ESP_037201_2450, NASA/JPL/Univ. of Arizona)

The VLT exoplanet hunter SPHERE is offered to the community

SPHERE, the extreme adaptive optics facility, high contrast imager spectrograph and polarimeter of the Very Large Telescope, is now offered to the community for P95 (April-Sept 2015, please look at the Call for Proposals). It has unique capabilities that make it a fantastic high-resolution, high-contrast disk imager with a field of view up to 11″ (much bigger than most of its main competitors). Material is available online to help you write your proposals.


SPHERE at VLT/UT3 © ESO/ J. Girard

SPHERE can lock its AO on fainter stars than GPI, up to R=11 for service mode and up to R~15 in visitor mode (with degraded AO performances of course). This is interesting for low-mass stars! Nevertheless, and unlike for NACO or SINFONI, the AO star must always be on-axis.

SPHERE IRDIS J-band images

SPHERE IRDIS J-band saturated, coronagraphic and processed images with a companion, iota Sgr b, a very low-mass star 4,000 times fainter at 0.24″ from its parent star.

AO preliminary performances of SPHERE SAXO

Simulated and measured (H-band, circles, by T. Fusco) SPHERE-SAXO Strehl ratio as a function of R magnitude. This is preliminary, result of 3 commissioning runs only! Check updates of the User Manual in the future months (just click on the image to get to the ESO SPHERE public pages).

SPHERE can also observe in visible light thanks to its imager/polarimeter ZIMPOL and access resolution of the order of 20 milliarcseconds thanks to its high order (over 1300 actuators deformable mirror) adaptive optics system SAXO.

I'-band observations with SPHERE/ZIMPOL

Left: binary star observed in I’-band centered at 790 nm (red light), the separation is 0.15″. Right: companion detected ~150,000 times (12 magnitudes) fainter than its parent star at only 0.2″. It’s a bit like distinguishing a candle right next to a light house from 500 miles!
(Data reduction: C. Thalmann)

Let’s congratulate the whole SPHERE consortium and ESO staff involved since many years with such a novel, complex but working instrument!

Which wind came first?

ESP_037156_1800_0.178xA piece of Mars: This scene (3.9×2.5 km or 2.4×1.6 mi) shows a surface carved by two different winds: one blowing from the right and one blowing from the bottom right. They’ve formed overlapping sets of streamlined rocks called yardangs. Can you tell which set of yardangs was formed first? It’s a little more complicated than it may first appear. (HiRISE ESP_037156_1800 NASA/JPL/Univ. of Arizona)

How the wind turns

ESP_037188_1835_0.603xA piece of Mars: The two shadowed hills in the upper part of this frame (497×373 m or 1631×1224 ft across) rest on a flat plain covered in large ripples. On the plain the ripples are aligned north-south, formed perpendicular to a wind blowing from the east (right). But those hills block the wind and turn it, so that the ripples between the hills change direction. This is how windblown landforms can be used as wind vanes in remote places (like on Mars). (HiRISE ESP_037188_1835, NASA/JPL/Univ. of Arizona)

Wind within vs. wind without

ESP_037195_1625_0257xA piece of Mars: Dunes outside the crater are straight but the ones inside the crater look like a spiderweb. Why? This image shows just how much the topography of a crater wall can affect the wind, which produces a much more complex set of dunes inside than out on the plains. (HiRISE ESP_037195_1625 NASA/JPL/Univ. of Arizona)

Kardashev Type III civilizations could be rare

These two papers by J.T. Wright’s group were posted today on astro-ph

The Ĝ Infrared Search for Extraterrestrial Civilizations with Large Energy Supplies. I. Background and Justification

J. T. Wright, B. Mullan, S. Sigurðsson, M. S. Povich

The Ĝ Infrared Search for Extraterrestrial Civilizations with Large Energy Supplies. II. Framework, Strategy, and First Result

J. T. Wright, R. Griffith, S. Sigurðsson, M. S. Povich, B. Mullan

Based on the analysis of WISE and Spitzer data, the authors concluded that “Kardashev Type III civilizations (a civilization that extracts fusion energy, information, and raw-materials from multiple solar systems) are very rare in the local universe”.

A Kardashev Type III civilization imagined.  Art by Jon Lomberg.

A Kardashev Type III civilization imagined. Art by Jon Lomberg.

I remind you that we had a SETI hangout on this topic with this group, including as well Jill Tarter and Freeman Dyson in September 2013.

I look forward to reading about the search for Kardashev Type II civilizations from the same set of data.

Clear Skies,

Franck M.


What on Mars?

ESP_037161_1785_1.0xA piece of Mars: What on Mars is this (the scene is 600×450 m, or 0.37×0.28 mi)? It can be hard to tell. The lines are ridges of windblown dunes or ripples, the dark gray stuff is active sand blowing between the dunes, and the underlying bedrock is pale tan. But if your eyes can’t make sense of it all, just sit back and enjoy the pretty patterns of Mars. (HiRISE ESP_037161_1785, NASA/JPL/Univ. of Arizona)

Small dunes up high, big dunes down low

ESP_036795_1760_0.331xA piece of Mars: This 1018×1352 m (0.63×0.84 mi) dune-covered scene has split topography: the the bottom part is up on a plateau, and the upper part is in a broad valley. The dunes up on the plateau are smaller than the ones in the valley. Why? Probably because there was more mobile dune-building sediment in the valley to begin with: the dunes up high ran out of material and stopped growing, but the ones in the valley kept getting bigger. (HiRISE ESP_036795_1760, NASA/JPL/Univ. of Arizona)

Summery dune

ESP_035997_2565_0.38xA piece of Mars: Last December I blogged about a picture of a sand dune taken in early northern spring. This is the same dune, without frost, now that summer has come to the northern hemisphere and all the frost is gone. It’s quite a difference. Apparently the dunes are controlled by ice in the winter and by the wind in the summer. (HiRISE ESP_035997_2565, NASA/JPL/Univ. of Arizona)

Is Generation Y Lost?

Here is another off the wall blog. You won’t find any physics in here…

Is GenY lost?
In a recent NYT article, Todd G. Buchholz and Victoria Buchholz, argue “sometime in the past 30 years, someone has hit the brakes and Americans—particularly young Americans—have become risk-aversive and sedentary.

University of New Hampshire management professor Paul Harvey says, GenY has a “very inflated sense of self” that leads to “unrealistic expectations” and “chronic disappointment.” If you want more silly expressions from old farts, read this article:

As for me, I identify very strongly with GenX; the previous ‘loser’ generation. In fact, generation X invented ‘loser.’ (Beck’s amazing anthem and L on the forehead). My birthday lands on the cusp of Baby Boomer and GenX, but I’ve clearly crossed the line into GenX I don’t live for or at my work. I think money isn’t everything. I’m not divorced, live within my means, and as a protest against pop culture, I stopped watching TV many years ago (although I do sometimes watch DVD’s). I had a ‘No Future’ sign on my office door in grad school, and my teachers were worried about it. I told them that with Reagan in office the Doomsday clock (Google it) was only 3 minutes to midnight (1984). And the Boomers complained that GenX was lazy, lost without a future (Ha! He says with bitter sarcasm), GenX can’t compete and they’ll never succeed like we (Boomers) did,

Well the joke is on the Boomers right now; they gradually fade away while GenX is taking over! Our president and I were born only 121 days apart! (My close approach to George Clooney, that’s right girls, is a mere 211 days). Thats right! GenX rules the world. Whole Foods plays GenX music (70′s – 90′s rock) right there in the aisles. As a GenX, I am the demographic for marketers — cause we have all the disposable income! Ha ha! Everyone treats me with respect cause I got a few gray hairs. No one complains about GenX anymore! It turns out that we’re pretty hard working and motivated after all! Ha ha!

So my message to my younger friends is to ignore oldsters who beat up your generation. You’re day will come!

Incidentally, I have a theory. I believe this “lazyness” ritual has been happening since the dawn of humanity. Every generation, so far, has been successful. We’re still around, aren’t we?

I’m not saying that GenY is not lazy. They’re young! This is how young humans are. Remember, the most impt. thing in your life when you’re young (say <30) is to find a partner and make babies. This ain’t easy; it requires a lot of talking, learning, and thinking about love and sex. Young people are too busy fulfilling the demands of their evolutionary drive to reproduce which after all, is a lot more fulfilling than being employee of the month at Starbucks.