Archive | April 2008

Conference Proceedings Published

The conference proceedings for “From Planets to Dark Energy: the Modern Radio Universe” have been published, we presented a poster on radio emission from exoplanets and briefly mentioned what else can be achieved by the wide fields possible at low radio frequencies. For more on the conference see [pos.sissa.it] and our conference proceedings can be found on [astro-ph]. The abstract for the poster was: “We present results from new low frequency observations of two extrasolar planetary systems (Epsilon Eridani and HD128311) taken at 150 MHz with the Giant Metrewave Radio Telescope (GMRT). We do not detect either system, but are able to place tight upper limits on their low frequency radio emission.”

How many moons does the Earth have?

A simple question, with an easy answer… well if you think it is as simple as 1 then you haven’t thought hard enough (seriously the answer is probably 1 but… ). Nothing new here but interesting nonetheless.
The near-Earth asteroid 3753 Cruithne is now known to be a companion, and an unusual one, of the Earth. This asteroid shares the Earth’s orbit, its motion “choreographed” in such a way as to remain stable and avoid colliding with our planet. It orbits around the Sun in 1:1 orbital resonance with that of the Earth. Due to its unusual orbit relative to that of the Earth, it is a periodic inclusion planetoid. From the Earth’s point of view Cruithne actually follows a kidney bean-shaped horseshoe orbit ahead of the Earth, taking slightly less than one year to complete a circuit (to see some diagrams of this take a look at [http://www.astro.uwo.ca/~wiegert]. Other examples of natural bodies known to be in horseshoe orbits include Janus and Epimetheus, natural satellites of Saturn. So maybe there is a case there?
It has been called “Earth’s second moon”. A term I find hard to agree with but I do like it, and in a way it could been deemed correct.
Cruithne is approximately 5 km in diameter, and its closest approach to Earth is approximately 30 times the separation between Earth and the Moon (12 million kilometres). Cruithne was discovered in 1986, so you have probably heard of it before… but if not this is some good trivia! A couple of others have been proposed in recent times including [http://www.astro.uwo.ca/~wiegert/]/
I would like to call 3753 Cruithne a moon, but it is not, it is a co-orbital asteroid, it shares our orbit. But what does this mean about the planet definition of an object clearing its path? biggrin.gif

Does the Sun Have a ‘Companion’?

A friend of mine mentioned the search for “Nemesis” the other day and I completely drew a blank. It seems that there are a bunch of people who think the Sun might have a ‘companion’ personally I’m not convinced but I do believe that there are probably some ultra cool stars in between us and Proxima Centauri (the closest stellar object we know of) that are yet to have been detected.
A good read can be found at: http://www.space.com/scienceastronomy/solarsystem/nemesis_010320-1.html and http://www.lbl.gov/Science-Articles/Archive/extinctions-nemesis.html – some interesting stuff but I wouldn’t believe all that you read!
If Nemesis exists, it may be detected by the planned Pan-STARRS or LSST astronomical surveys, or similar future projects. If Nemesis is a brown dwarf, then the upcoming WISE mission should find it (and it should be quite easy!).

The coolest brown dwarf

You may not know (you probably do if you come here often enough) but there are a class of objects that are too massive to be planets but not massive enough to have sustainable fusion – these are known as brown dwarfs (or ultra cool stars). This is one of the major aspects of my current research and the reason I went over to India earlier in the year… anyway some interesting stuff has been released about them – so I thought you might be interested in reading about it and seeing why I am so inspired to work on this stuff.. oh and for you UK taxpayers, don’t worry I didn’t waste too much time in India… biggrin.gif

An international team of astronomers has discovered the coldest brown dwarf ever observed, bringing scientists one step closer to bridging the gap between stars and planets.

Take a longer read at the full article at [astronomynow.com]

Best 404 ever…

yes, its a game… time to waste some time breaking blocks!!
[best 404].

How to get USB working for VirtualBox in Ubuntu

In Ubuntu Gusty some changes were made to the way it handles usb, anyway to get USB support for Virtual Box you need to edit `/etc/init.d/mountdevsubfs.sh and uncomment the 4 lines around line 40 (Magic to make /proc/bus/usb work). Then execute /etc/init.d/mountdevsubfs.sh start – this will then enable the use of USB in Virtual Box (oh you probably want to do the above as sudo).
Now there is a nice and geeky post biggrin.gif

10th talk in the Patrick Moore Series!!

I have to say I’m really proud to announce the 10th talk in the public lecture series that I’m one of the organizers of at the University of Birmingham…
Our next public talk is to take place on the 8th May at 7:30pm
The 10th “Patrick Moore” lecture
[www.talkandtelescope.org.uk]
Dr Mike Hapgood (Space Environment Group; Rutherford Appleton Laboratory)
“Space Weather and Lunar Exploration”
OPEN TO THE GENERAL PUBLIC
The talk starts at 7:30pm on Thursday 8th May
Poynting Physics S02 (LLT)
Snacks and tea in the Study lounge from 7pm before the talk
If clear, sky viewing with telescopes with the help of Astrosoc members after the talk
Talk synopsis:
The Moon is embedded in the space plasma environments that surround the Earth. As a result, it is exposed to a range of space weather effects including radiation, electrical charging and electromagnetic induction. These effects have profound implications for lunar exploration. Radiation is a health hazard to human explorers but also poses a risk to robots by disrupting and damaging electronic devices. Electrical charging of the lunar surface poses several problems. It is thought to be the primary process driving the transport of lunar dust above and across the lunar surface, so studies of charging underpin studies of the threat that dust poses to lunar exploration. Electrical charging is also a direct threat to systems deployed on the lunar surface since it may induce electrical discharges that can disrupt or damage electronic devices in those systems. Electromagnetic induction inside the Moon arises when it is exposed to large scale changes in the electric and magnetic fields embedded in the space plasma environment. It poses little or no immediate risk to exploration activities as the systems to be deployed on the Moon are fairly small, but it can be exploited as a tool for exporation of the lunar interior. The talk will review these effects and discuss how they change with the natural cycles of solar activity and the Moon’s orbital motion. It will also discuss the Apollo experience of these effects and show how it influences of our current understanding. Finally, the talk will look ahead and highlight some important lessons for future exploration.
Speaker Bio:
Mike Hapgood is Head of the Space Environment Group at the Rutherford Appleton Laboratory in Oxfordshire. He has a long involvement in solar-terrestrial physics and space weather. He has worked on the ESA Cluster project for many years and is lead scientist for the ESA-funded Cluster operations centre at RAL. He has also led several ESA studies on space weather projects and is current Chair of the ESA Space Weather Working Team. He also served on the recent BNSC Space Exploration Working Group. His current interests include the impact of space weather on lunar exploration and the application of space plasma concepts in other astrophysical environments.
This series of talks is funded by STFC http://www.scitech.ac.uk/, (Public
Understanding of Science grant), and is organised by the School of Physics
and Astronomy http://www.ph.bham.ac.uk and the Astronomical Society of UoB
AstroSoc http://www.astrosoc.org.uk)
For more information about our outreach activities visit:
http://www.talkandtelescope.org.uk

Wonderful picture of Phobos

According to APOD (I agree by the way)… Phobos is doomed, it orbits very close to Mars – about 5,800 kilometers above the surface compared to 400,000 kilometers for our Moon!! This means that the tidal forces are dragging it down and due to this stress it is likely to cause it to shatter, in 100 million years or so!
The reason I post this, well look at the fantastic photo that has been released of this object:
Photobucket
Credit: HiRISE, MRO, LPL (U. Arizona), NASA
For more and a larger image see: [APOD]

Physics Funding – the government responds

If you have been following the physics budget crisis with eager eyes then I urge you to take a look at the governments response to an online epetition to Downing St – [see here]. Personally I’m not to shocked with the response “but we have increased funding over the last few years”. I expected nothing more than this, and to be honest its not really there fault – its the STFC. Anyway, without trying to blame anyone, I urge you to read the facts. The only thing I’m going to comment on is this paragraph: “*This will ensure that the number of Astronomy post-doctoral research assistants funded in 2008, remains roughly level.” Ok thats true, for 2008 it is… but after then the number will drop hugely… and so will start the brain drain as young scientists, like myself, look for jobs elsewhere. Oh and I thought it was very funny the way they mention the USA government… do we bow down to them on science as well now…. mad.gif

Messing about with Ubuntu

I’m a bit unsure what the title of this entry should be and I’m a bit unsure about what I should actually mention. I had intended this to be a collection of things I did after I had installed Ubuntu on my machine. This could be, for some of you, the most boring entry you have ever seen. Hopefully some of the geekier readers will like this. I’m still not sure what is going to go here / if it will be of use for anyone. At least I will use it as a point of reference for myself. Hell that’s what this blog is all about. It is about me being too lazy to keep detailed notes and diaries.. and hopefully to give some of you an insight into my mind and what I’m upto. Lets be honest I’m pretty sure my most dedicated reader is my Mom (hi Mom – trust me this entry is not one for you… but if any of this sounds better than that Microsoft Vista installation I dumped on you…!biggrin.gif).
Oh well here goes. Hopefully this might inspire some of you to give Ubuntu a go, its simple really and to install you just pop in the cd and off you go…
Audio Visual

Probably the most important, lets get some metal on while we do the rest…
Sort out your soundcard…
[http://ubuntuforums.org]

Install Mplayer and Multimedia Codecs (libdvdcss2,w32codecs) in Ubuntu 7.10 (Gutsy Gibbon)
“MPlayer is a movie and animation player that supports a wide range of codecs and file formats, including MPEG 1/2/4,DivX 3/4/5, Windows Media 7/8/9, RealAudio/Video up to 9, Quicktime 5/6, and Vivo 1/2. It has many MX/SSE (2)/3Dnow(Ex) optimized native audio and video codecs, but allows using XAnim’s and RealPlayer’s binary codec plugins, and Win32 codec DLLs. It has basic VCD/DVD playback functionality, including DVD subtitles, but supports many text- based subtitle formats too. For video output, nearly every existing interface is supported. It’s also able to convert any supported files to raw/divx/mpeg4 AVI (pcm/mp3 audio), and even video grabbing from V4L devices.”
[http://www.ubuntugeek.com]

Use amarok for your music! works great with your ipod… sudo apt-get install amarok – and you can use it with last.fm – and there are tons of scripts out there! [amarok]

Copying DVDs (note: this is for legit purposes…) – XDVDShrink: [XDVDShrink]
This and some important codecs can all be installed using Automatix2 – [Automatix2]

Mounting your disks…

How to fstab – [http://ubuntuforums.org]
The configuration file /etc/fstab contains the necessary information to mount the disk. This file comes read at the start of the system and can be modified only by root user. [ubuntu.com]
How to edit and understand /etc/fstab [tuxfiles.org]
I finally got it to work by setting up the fstab correctly and then chown the directory it was mounted so I owned it! This took me longer to think of than I would have expected, silly brain as it was a pretty obvious thing to do.
Reading NTFS disks, Ubuntu Gutsy did this for me ok but for reference [ubuntuforums.org].

Booting

Grubb issues, don’t we love to hate it! 😀
How to restore Grub from a live Ubuntu cd [ubuntuforums.org]
Recovering Ubuntu after installing Windows – if you dual boot: [help.ubuntu.com]
(I’d suggest you don’t dual boot.. well if you only want to use a few windows task or play simple games – if this is you then think Wine or booting windows in a virtual machine).

Run other operating system’s inside Ubuntu!

Virtualbox, how to: http://howtoforge.com/virtualbox_ubuntu
Create and Manage Virtual Machines Using VirtualBox: [www.ubuntugeek.com]
Once installed remember to add yourself to the group that can use Virtualbox – if stuck try this page (note in French!): [doc.ubuntu-fr.org]

Windows apps inside Ubuntu
Wine is what you want, and irfan view rocks for image manipulation: [help.ubuntu.com]
How to run Windows applications on Ubuntu – [www.zolved.com] (this use a gui interface for adding packages, I’d recommend you use the above one which uses the commandline and apt-get, much faster if you can deal with the fear of not clicking…)

Mail

Copying over thunderbird files from Windows: copied over files and then edited profiles.ini so path was the old one…
[General]
StartWithLastProfile=1

[Profile0]
Name=default
IsRelative=1
Path=b1na6jtf.default

.. open up thunderbird and there you go, all your files and settings! ref: [ubuntuforums.org]

Backup

Making system images – VERY USEFUL!! Why repeat all of the above and below ever again! Creating Custom Ubuntu Live-CD With Remastersys: [www.ubuntugeek.com]
Create, Recover and Automate System Images – the above did the trick for me so I did not use the below in the end but its worth a look at: [ubuntuforums.org]
How to create an ISO image, pretty straightforward but always useful to check! [www.tech-recipes.com]
Simple Ubuntu Desktop Backup with Backerupper – I haven’t tried this yet, I have rsync scripts todo my backup in conjuction with crontab… [www.ubuntugeek.com]
Backup Ubuntu using rdiff-backup – I’m guessing this is similar to rsync, I haven’t tried this yet. When I get chance I should add some stuff on rsync: [www.ubuntugeek.com]
Backup and Restore Your Ubuntu System using Sbackup – a GUI, I might run scared but this is probably very useful for the person who runs scared of the commandline 😀 (I used to have that fear!) [www.ubuntugeek.com] (more on this at: [www.zolved.com])

Networking

How to open bittorrent ports from the command line: [www.ubuntugeek.com]
Ubuntu Firewall confusion, interesting posts about opening ports in ubuntu: [ubuntuforums.org]
Installing a firewall… I haven’t done this – I have a hardware firewall and ubuntu does not have open ports: [www.linux.com]

Misc

13 Things to do immediately after installing Ubuntu – some are obvious and some seem already there, [linuxondesktop.blogspot.com] – I’m also recommend the ubuntuguide.org
JAVA – [www.javalobby.org]
Epiphany Browser – nice and light weight.. [ubuntu-tutorials.com]
Fonts – not really needed, but oh one likes to play… [ubuntu.wordpress.com] [www.zolved.com] and how to install Microsoft fonts, but there is some copyright issues – I haven’t done this: [ubuntu.wordpress.com]
Enable Smooth fonts on Ubuntu Linux – [www.howtogeek.com] – I’m not sure this really made much of a difference!
XBOX 360 Controller, I’m still to try this one… [ubuntuforums.org]
Keyboard shortcuts – [ubuntuforums.org]
SKYPE – don’t get me started, this is the only thing I’m having problems with (though its really the usb phone and not skype)! [help.ubuntu.com]

Interesting sites

[www.ubuntugeek.com]
[www.brunolinux.com]
[fullcirclemagazine.org]
[www.justuber.com]
What app do you need? [www.gnomefiles.org]

To all you wannabe converts, remember that Linux is not Windows! Its much better 😀 [http://linux.oneandoneis2.org/LNW.htm”]
How to get good help on linux forums, interesting read, [ubuntucat.wordpress.com]