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Magnus Persson
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Installing IRAM GILDAS on Ubuntu (2014/05)
What is IRAM GILDAS? See here : Since I just got new hardware, I will update this guide soon, for Xenial Xerus 16.04. NOTE: Updated for Ubuntu 14.04 Trusty Tahr. Should work for anything >11.04. First download the source c...

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Screen brightness Fn keys in i3wm Lenovo Thinkpad X260
Note: this is a first draft, I just want to jot down what  I currently have. I got a new laptop for work, Lenovo Thinkpad X260. Installed Ubuntu 16.04 Xenial Xerus without much problem. There are several Fn-hotkeys for the F1-F12 keys, most of them do not w...

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Off-topic : TP-Link WN725N v2 Wireless on the Raspberry PI
TP-Link WN725N v2 on Raspberry Pi at N speeds (150 Mbps). So I managed to get the wireless nano-dongle work on one of the Raspberry Pi's. It's a TP-Link WN725N version 2. It has N capabilities, and it wasn't easy making sure I got N speeds either, more on t...

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Fireworks designed for daytime viewing
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Towing an asteroid into L2. The candidates.
Aerospace engineers have identified 12 asteroids we could capture using existing rocket technology.

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Why every scientist should pay attention to Google Scholar

Google Scholar is an alternative to Web of science kind of tools which lets you search through the plethora of research articles available (open access or behind a pay-wall) on internet. 

Here is why I am cheer-leading for it: 

Free - It is FREE! Much like the NASA ADS service.

Access - The best thing about Google Scholar is that it searches the whole freakin internet and many a times it finds the pdf files of otherwise pay-walled articles on some university/collaboration/homepage websites and it displays it along the article (see the attached image). This feature can be a life saver (or an anxiety remedy :) ) while you are travelling. 

Research profile - In Google scholar you can create your profile and add your research articles. Google scholar will update all of your citations regularly. It also includes citations from conference proceedings and arxiv submissions. Counting arxiv articles as citations could be useful in those cases when researchers upload their research papers immediately after submitting it to a peer-reviewed journal. And, as you might know, the peer-review could take a lot of time and some times it is very useful to know what the submitted article is about even though it hasn't been peer-reviewed. My profile:

Copy citations - You can copy citation information directly from the Google scholar search results! This lets you avoid the gruesome hunting for citation information on journal websites. More info:

Scholar update - Using keywords from your papers, it regularly provides research updates.

Popular journals - Recently, they added a feature in which you can see the highly cited journals in a particular field of research. More info:

There you have it folks, free and awesome stuff! Do yourself a favor on this #sciencesunday   and explore Google Scholar, and if you are an active researcher, then make a profile. 

For +ScienceSunday, curated by +Robby Bowles , +Allison Sekuler , +Rajini Rao , +Chad Haney , and +Buddhini Samarasinghe .

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Super cool!
A Living Mars

A conception of an ancient and/or future Mars, flush with oceans, clouds and life.

This is a view of the Western hemisphere with Olympus Mons on the horizon beyond the Tharsis Montes volcanoes and the Valles Marineris canyons near the center. The height of the clouds and atmosphere are largely arbitrary and set for the sake of appearance and coverage over the exaggerated terrain elevations (~10 times elevation exaggeration). The eye is about 10,000 km (~6,200 miles) from the surface. 

The completed model was done in several steps... 

A two dimensional digital elevation model was first rendered in jDem846 (an open-source learning project of mine) using the MRO MOLA 128 pix/deg elevation dataset. In that model, I picked a sea level and scripted it such that terrain at or below that level was flat and blue. 

The resulting model was then brought into GIMP were I painted in land features using a NASA Blue Marble Next Generation image for the source textures.  There is no scientific reasoning behind how I painted it; I tried to envision how the land would appear given certain features or the effects of likely atmospheric climate. For example, I didn’t see much green taking hold within the area of Olympus Mons and the surrounding volcanoes, both due to the volcanic activity and the proximity to the equator (thus a more tropical climate). For these desert-like areas I mostly used textures taken from the Sahara in Africa and some of Australia. Likewise, as the terrain gets higher or lower in latitude I added darker flora along with tundra and glacial ice. These northern and southern areas textures are largely taken from around northern Russia. Tropical and subtropical greens were based on the rainforests of South America and Africa. 

Finally, that image was brought back into jDem846 as a layer to be reapplied to the same MOLA dataset, but rendered as a spherical projection (like Google Earth).  I scripted the model to apply a three-dimensional cloud layer, add an atmosphere, and dampen specular lighting on dry land and under clouds. There are some other scripted tweaks here and there. 

This wasn’t intended as an exhaustive scientific scenario as I’m sure (and expect) some of my assumptions will prove incorrect. I’m hoping at least to trigger the imagination, so please enjoy!

Some of the source images, jDem846 project files and earlier revisions are available here: 

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Ballons are evil.
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