What is BitLocker

BitLocker Drive Encryption is a full disk encryption feature included with the Ultimate and Enterprise editions of Microsoft's Windows Vista and Windows 7 desktop operating systems, as well as the Windows Server 2008 and Windows Server 2008 R2 server platforms. It is designed to protect data by providing encryption for entire volumes. By default it uses the AES encryption algorithm in CBC mode with a 128 bit key, combined with the Elephant diffuser for additional disk encryption specific security not provided by AES.

BitLocker is available only in the Enterprise and Ultimate editions of Windows Vista and Windows 7. Users of other versions of Windows that don't include BitLocker could use a 3rd party encryption program to satisfy the need for full drive encryption (see Comparison of disk encryption software). In the RTM release of Windows Vista, only the operating system volume could be encrypted using the GUI and encrypting other volumes required using WMI-based scripts included in Windows Vista in the %Windir%\System32 folder.  An example of how to use the WMI interface is in the script manage-bde.wsf, that can be used to set up and manage BitLocker from the command line. With Windows Vista Service Pack 1 and Windows Server 2008, volumes other than the operating system volume can be BitLocker-protected using the graphical Control Panel applet as well.

The latest version of Bitlocker, included in Windows 7 and Windows Server 2008 R2, adds the ability to encrypt removable drives.

Overview

There are three authentication mechanisms that can be used as building blocks to implement Bitlocker encryption:

Transparent operation mode: This mode exploits the capabilities of Trusted Platform Module (TPM) 1.2 hardware to provide for a transparent user experience—the user powers up and logs onto Windows as normal. The key used for the disk encryption is sealed (encrypted) by the TPM chip and will only be released to the OS loader code if the early boot files appear to be unmodified. The pre-OS components of BitLocker achieve this by implementing a Static Root of Trust Measurement—a methodology specified by the Trusted Computing Group. This mode is vulnerable to a cold boot attack, as it allows a powered-down machine to be booted by an attacker.

User authentication mode: This mode requires that the user provide some authentication to the pre-boot environment in the form of a pre-boot PIN. This mode is vulnerable to a bootkit attack.

USB Key Mode: The user must insert a USB device that contains a startup key into the computer to be able to boot the protected OS. Note that this mode requires that the BIOS on the protected machine supports the reading of USB devices in the pre-OS environment. This mode is also vulnerable to a bootkit attack.

Recovery password: A numerical key protector for recovery purposes.

Recovery key: An external key for recovery purposes.

Certificate: Adds a certificate-based public key protector for recovery purposes.

Password: Adds a password key protector for a data volume.

The following permutations of the above authentication mechanisms are supported, all with an optional escrow recovery key:

TPM only

TPM + PIN

TPM + PIN + USB Key

TPM + USB Key

USB Key

Operation

Contrary to the official name, BitLocker Drive Encryption is a logical volume encryption system. A volume may or may not be an entire drive, and can span one or more physical drives. Also, when enabled TPM/Bitlocker can ensure the integrity of the trusted boot path (e.g. BIOS, boot sector, etc.), in order to prevent most offline physical attacks, boot sector malware, etc.

In order for BitLocker to operate, the hard disk requires at least two NTFS-formatted volumes: one for the operating system (usually C:) and another with a minimum size of 100MB from which the operating system boots. BitLocker requires the boot volume to remain unencrypted—on Windows Vista this volume must be assigned a drive letter, while on Windows 7 it does not. Unlike previous versions of Windows, Vista's "diskpart" command-line tool includes the ability to shrink the size of an NTFS volume so that the system volume for BitLocker can be created from already-allocated space. A tool called the "Bitlocker Drive Preparation Tool" is also available from Microsoft that allows an existing volume on Windows Vista to be shrunk to make room for a new boot volume, and for the necessary bootstrapping files to be transferred to it;Windows 7 creates the secondary boot volume by default, even if Bitlocker is not used initially.

Once an alternate boot partition has been created, the TPM module needs to be initialized (assuming that this feature is being used), after which the required disk encryption key protection mechanisms such as TPM, PIN or USB key are configured. The volume is then encrypted as a background task, something that can take a considerable amount of time with a large disk as every logical sector is read, encrypted and rewritten back to disk. Only once the whole volume has been encrypted are the keys protected, and the volume considered secure. BitLocker uses a low-level device driver to encrypt and decrypt all file operations, making interaction with the encrypted volume transparent to applications running on the platform.

Encrypting File System may be used in conjunction with BitLocker to provide protection once the operating system kernel is running. Protection of the files from processes/users within the operating system can only be performed using encryption software that operates within Windows, such as Encrypting File System. BitLocker and Encrypting File System therefore offer protection against different classes of attacks.

In Active Directory environments, BitLocker supports optional key escrow to Active Directory, although a schema update may be required for this to work (i.e. if the Active Directory Directory Services are hosted on a Windows version previous to Windows Server 2008).

Other systems like BitLocker can have their recovery key/password entry process spoofed by another bootmanager or OS install. Once the spoofed software captured the secret, it could be used to decrypt the Volume Master Key (VMK), which would then allow access to decrypt or modify any information on the user's BitLocker-encrypted hard disk. By configuring a TPM to protect the trusted boot pathway, including the BIOS and boot sector, this threat can be removed.

Security concerns

According to Microsoft sources, BitLocker does not contain an intentionally built-in backdoor; there is no way for law enforcement to have a guaranteed passage to the data on the user's drives that is provided by Microsoft. The lack of any backdoor has been a concern to the UK Home Office, which tried entering into talks with Microsoft to get one introduced, though Microsoft developer Niels Ferguson and other Microsoft spokesmen state that they have not granted the wish to have one added. Although the AES encryption algorithm used in Bitlocker is in the public domain, its actual implementation in BitLocker, as well as other components of the software, are closed source; however, the code is available for scrutiny by Microsoft partners and enterprises, subject to a non-disclosure agreement.

Notwithstanding the claims of Niels Ferguson and others, Microsoft Services states in Exploration of Windows 7, Advanced Forensics Topic "BitLocker has a number of 'Recovery' scenarios that we can exploit", and "BitLocker, at its core, is a password technology, we simply have to get the password...".

The "Transparent operation mode" and "User authentication mode" of BitLocker use the TPM hardware to detect if there are unauthorized changes to the pre-boot environment, including the BIOS and MBR. If any unauthorized changes are detected, BitLocker requests a recovery key on a USB device, or a recovery password entered by hand. Either of these cryptographic secrets are used to decrypt the Volume Master Key (VMK) and allow the bootup process to continue.

Nevertheless, in February 2008, a group of security researchers published details of a so called "cold boot attack" that allows a Bitlocker-protected machine to be compromised by booting the machine off removable media, such as a USB drive, into another operating system, then dumping the contents of pre-boot memory. The attack relies on the fact that DRAM retains information for up to several minutes (or even longer if cooled) after power has been removed. Use of a TPM module alone does not offer any protection, as the keys are held in memory while Windows is running, although two-factor authentication, i.e. using TPM together with a PIN, offers better protection for machines that are not powered on when physical access to them is obtained. Similar full disk encryption mechanisms of other vendors and other operating systems, including Linux and Mac OS X, are vulnerable to the same attack. The authors recommend that computers be powered down when not in physical control of the owner (rather than be left in a "sleep" state) and that a password also be required to boot the machine.

Once a Bitlocker-protected machine is running, its keys are stored in memory where they may be susceptible to attack by a process that is able to access physical memory, for example through a 1394 DMA channel. Any cryptographic material in memory is at risk from this attack, which is therefore not specific to Bitlocker.

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Why does Windows Partition Manager leaves 8 MB free space at the end of the Disk

The Windows Partition Manager leaves about 8 MB of unallocated disk space at the end of the disk. This space is reserved by Setup in case you later want to upgrade the Basic Disk to a Dynamic Disk. Dynamic disk information is saved at the end of the disk. The amount that is reserved is a minimum of one cylinder, or 1MB, whichever is greater. One cylinder can be up to 8MB, depending on drive geometry and translation.


Basic Disk Storage

Basic storage uses normal partition tables supported by MS-DOS, Microsoft Windows 95, Microsoft Windows 98, Microsoft Windows Millennium Edition (Me), Microsoft Windows NT, Microsoft Windows 2000, and Windows XP. A disk initialized for basic storage is called a basicdisk. A basic disk contains basic volumes, such as primary partitions, extended partitions, and logical drives. 

Additionally, basic volumes include multidisk volumes that are created by using Windows NT 4.0 or earlier, such as volume sets, stripe sets, mirror sets, and stripe sets with parity. Windows XP does not support these multidisk basic volumes. Any volume sets, stripe sets, mirror sets, or stripe sets with parity must be backed up and deleted or converted to dynamic disks before you install Windows XP Professional.

Dynamic Disk Storage

Dynamic storage is supported in Windows 2000 and Windows XP Professional. A disk initialized for dynamic storage is called a dynamic disk. A dynamic disk contains dynamic volumes, such as simple volumes, spanned volumes, striped volumes, mirrored volumes, and RAID-5 volumes. 

Not every Operating System (OS) supports Dynamic disks. Dynamic disks are only supported by Windows XP, Vista Ultimate, Vista Enterprise and Windows 7. Windows XP Home Edition does not support dynamic disks.


NOTE: Dynamic disks are not supported on portable computers or on Windows XP Home Edition-based computers. 

You cannot create mirrored volumes or RAID-5 volumes on Windows XP Home Edition, Windows XP Professional, or Windows XP 64-Bit Edition-based computers. However, you can use a Windows XP Professional-based computer to create a mirrored or RAID-5 volume on remote computers that are running Windows 2000 Server, Windows 2000 Advanced Server, or Windows 2000 Datacenter Server. You must have administrative privileges on the remote computer to do this.

Storage types are separate from the file system type. A basic or dynamic disk can contain any combination of FAT16, FAT32, or NTFS partitions or volumes. 

A disk system can contain any combination of storage types. However, all volumes on the same disk must use the same storage type.

General Information

• On a basic disk, a partition is a portion of the disk that functions as a physically separate unit. On a dynamic disk, storage is divided into volumes instead of partitions.
• Storage types are separate from the file system type; a basic or dynamic disk can contain any combination of FAT16, FAT32, and NTFS partitions or volumes.
• Windows XP Professional accommodates both basic and dynamic storage. A disk system can contain any combination of storage types. However, all partitions or volumes on the same disk must use the same storage type (Basic or Dynamic).

How to convert a Basic Disk into Dynamic Disk

General Notes

Before you change a basic disk to a dynamic disk, note these items:

• You must have at least 1 megabyte (MB) of free space on any master boot record (MBR) disk that you want to convert. This space is automatically reserved when the partition or volume is created in Microsoft Windows 2000 or Windows XP Professional. However, it may not be available on partitions or volumes that are created in other operating systems.
• When you convert to a dynamic disk, the existing partitions or logical drives on the basic disk are converted to simple volumes on the dynamic disk.
• After you convert to a dynamic disk, the dynamic volumes cannot be changed back to partitions. You must first delete all dynamic volumes on the disk, and then convert the dynamic disk back to a basic disk. If you want to keep your data, you must first back up or move the data to another volume.
• After you convert to a dynamic disk, local access to the dynamic disk is limited to Windows XP Professional and Windows 2000.
• If your disk contains multiple installations of Windows XP Professional or Windows 2000, do not convert to a dynamic disk. The conversion operation removes partition entries for all partitions on the disk with the exception of the system and boot volumes for the current operating system.
• Dynamic disks are not supported on portable computers or Microsoft Windows XP Home Edition.

Before you change a dynamic disk back to a basic disk, note that all existing volumes must be deleted from the disk before you can convert it back to a basic disk. If you want to keep your data, back up the data, or move your data to another volume. 

How to Convert a Basic Disk to a Dynamic Disk

To convert a basic disk to a dynamic disk:

1. Log on as Administrator or as a member of the Administrators group.
2. Click Start, and then click Control Panel.
3. Click Performance and Maintenance, click Administrative Tools, and then double-click Computer Management.
4. In the left pane, click Disk Management.
5. In the lower-right pane, right-click the basic disk that you want to convert, and then click Convert to Dynamic Disk. 
   
   NOTE:You must right-click the gray area that contains the disk title on the left side of the Details pane. For example, right-click Disk 0.
6. Select the check box that is next to the disk that you want to convert (if it is not already selected), and then click OK.
7. Click Details if you want to view the list of volumes in the disk.
8. Click Convert.
9. Click Yes when you are prompted to convert, and then click OK.

How to Convert a Dynamic Disk to a Basic Disk

To change a dynamic disk back to a basic disk:

1. Back up all the data on all the volumes on the disk you want to convert to a basic disk.
2. Log on as Administrator or as a member of the Administrators group.
3. Click Start, and then click Control Panel.
4. Click Performance and Maintenance, click Administrative Tools, and then double-click Computer Management.
5. In the left pane, click Disk Management.
6. Right-click a volume on the dynamic disk that you want to change to a basic disk, and then click Delete Volume.
7. Click Yes when you are prompted to delete the volume.
8. Repeat steps 4 and 5 for each volume on the dynamic disk.
9. After you have deleted all the volumes on the dynamic disk, right-click the dynamic disk that you want to change to a basic disk, and then click Convert to Basic Disk. 
   
   NOTE:You must right-click the gray area that contains the disk title on the left side of the Details pane. For example, right-click Disk 1.

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What is Master Boot Record ( MBR ) ?

Each hard-drive (or Cd or other drive or device) has only 1 Master Boot Record. It is in a fixed position on the hard-drive. The MBR is the sector at cylinder 0, head 0, sector 1 of any hard disk or diskette that identifies how and where an operating system is located so that it can be boot (loaded) into the computer's main storage or random access memory.

The Master Boot Record is also sometimes called the "partition sector" or the "master partition table" because it includes a table that locates each partition that the hard disk has been formatted into. In addition to this table, the MBR also includes a program that reads the boot sector record of the partition containing the operating system to be booted into RAM. In turn, that record contains a program that loads the rest of the operating system into RAM.

The MBR, the most important data structure on the disk, is created when the disk is partitioned. The MBR contains a small amount of executable code called the master boot code, the disk signature, and the partition table for the disk. At the end of the MBR is a 2-byte structure called a signature word or end of sector marker, which is always set to 0x55AA. A signature word also marks the end of an extended boot record (EBR) and the boot sector.

The disk signature, a unique number at offset 0x01B8, identifies the disk to the operating system.

The values in the partition table (contained in the MBR) depend directly on the size of the physical disk and on the logical partitioning on that disk. The DOS Boot Record (DBR) holds the Boot Parameter Block (BPB), which contains the logical mapping information for that particular partition. The values in the Boot Parameter Block are absolutely dependent on the size of the partition and the type of file system.

 

In the above picture, is an example of what a partitioned hard disk drive may look like. In this case, the MBR is the first section of the hard disk drive the computer looks at after the BIOS hands control to the first bootable drive.

These two sectors contain the information necessary to locate and identify the file system used to access the data on the drive. If either of these are damaged, the data becomes inaccessible, even though there may be no damage to the data or the file system itself.

Contrary to popular belief the Mbr does NOT belong to the operating system, it belongs to the drive or device. Often people may say "the Windows Mbr gets broken" but what this really means is that the drive's Mbr will no longer point at Windows.

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Linux Mint 11 and Fedora 15: In One Week, Two Gems Debut

It's not every week that sees the launch of a major release from one of the most popular Linux distributions. This week, however, we've had the benefit of not just one but two such landmark debuts.

Wondering what you'll find in these new releases? Here's a rundown of some of their key new features.

Fedora 15 'Lovelock'

As promised previously, the final release of Fedora 15 launched on Tuesday to a global audience of fans eager to check out its implementation of the GNOME 3 desktop.

Linux desktops are a particularly critical subject, of course, now that the default Unity desktop in Ubuntu 11.04 "Natty Narwhal" has proven so controversial, and the Fedora team announced that it was abandoning its own Unity efforts some time ago. GNOME 3 may be slightly less controversial, but it's still generating a lot of discussion.

Other key new features in this latest release from Fedora--which is currently the third most popular Linux distribution, according to DistroWatch--are the availability of the Btrfs filesystem as a menu item in the installer and better crash reporting.

A redesigned SELinux troubleshooter is also a part of the new release, as is higher compression in live images. Lovelock features better power management as well, thanks in part to a daemon that tunes system settings dynamically to balance between power consumption and performance.

LibreOffice and Firefox 4 are now included, while updates for systems administrators include a dynamic firewall, more consistent network device naming and the BoxGrinder appliance creator. A full list of features is available on the Fedora site, where the new release is also available for free download.

Linux Mint 11 'Katya'

Behind only Ubuntu in popularity on DistroWatch's list, Linux Mint is a very user-friendly Ubuntu-based distribution, as I've noted before. This new release, meanwhile, has been widely anticipated as an alternative option for those who aren't enchanted by Ubuntu's Unity.

Released on Thursday, Linux Mint 11 "Katya" uses neither Unity nor GNOME 3; rather, the project developers chose to stick with GNOME 2.32 instead, providing a comfortable and familiar option for fans of that desktop environment.

The software is still based on Ubuntu 11.04, however, and features one-click installation of multimedia codecs and extra applications. The Software Manager has been enhanced with user interface improvements, a new splash screen and better search capabilities, while the Update Manager offers better performance as well as improvements to its user interface.

Improvements to the Desktop Settings tool make it more "desktop-agnostic," the project team says, while system improvements include a new "apt download" command and Adobe Flash plugins.

LibreOffice, gThumb and Banshee are among the default applications in Katya, which is available for free download on the Linux Mint site.

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Mozilla releases Firefox 5 beta with improved performance and added developer support

 

After taking nearly three years to deliver Firefox 4, Mozilla has beta-released Firefox 5 just two months after. The first beta in Mozilla’s newrapid release development cycle, Firefox 5 beta does not feature as many interface and framework changes that Firefox 4 had over Firefox 3.

Trying to stay up-to-date and ahead of the curve, the new strategy will enable Mozilla to deliver frequent stable updates, and bring new features to users faster, like Google does with Chrome. Changes in Firefox 5 beta include:

• Added support for CSS animations
• Added support for switching Firefox development channels
• The Do-Not-Track header preference has been moved to increase discoverability
• Improved canvas, JavaScript, memory, and networking performance
• Improved standards support for HTML5, XHR, MathML, SMIL, and canvas
• Improved spell checking for some locales
• Improved desktop environment integration for Linux users

The new features and supported standards are primarily for developers to exploit, though regular Firefox enthusiasts will be pleased with the improved and faster switching between one of the three main development channels, Aurora, Beta, and Release. Linux users will also appreciate the added stability.

 

By the time Firefox 5 rolls out - hopefully by June 21st, as Mozilla had announced - there will definitely be more end-user features and interface improvements in tow, with popular Mozilla Labs' tweaks finding their way to the full release.

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Western Digital Caviar Green WD20EARS 2TB SATA Hard Drive

May 11 2011 - For anyone looking to add a large amount of storage to their desktop computer or just have a drive that produces very little noise or heat, the Western Digital WD20EARS 2TB SATA drive is a solid choice. While its performance is not suited for those wanting high performance, it does a great job as a secondary storage or backup drive. Performance is still good all while being very quiet and cool to the touch. It also offers some a great price per gigabyte. The downside is that the drive is not suited for use in RAID arrays and the three year warranty is less than some of the competition or Western Digital's own Caviar Black series.

Pros

• Large Storage Capacity
• Good Price Per Gigabyte
• Runs Very Quiet And Cool

Cons

• Not Suited For RAID Usage
• Three Year Warranty Less Than More Expensive Drives Or Some Of The Competition

Description

• 2TB (1.81TB Formatted) Storage Capacity
• 3.5-inch Internal Desktop Form Factor
• Variable Rotational Speed
• 64MB Cache
• SATA 3.0 Gbps Interface
• 24dBA/29dBA Idle/Seek Accoustics
• 4.5W Read/Write, 2.5W Idle, .7W Sleep/Standby Power Consumption
• Three Year Warranty

Western Digital's Caviar Green series of drives are designed for high capacity and low power consumption. In fact, the largest drives that are available for desktop PCs tend to be sold among the green class of drives. The WD20EARS may not be the highest capacity drive on the market, but it is an important capacity because many older desktop computers and operating systems can't properly handled drives larger than 2TB. As a result, this is the best capacity choice for those with older computers but it also works well for those with new computers who need some serious storage space. And with prices as low as $80, this makes for a very good price per gigabyte.

In order to achieve the low power consumption and lower operating noise and heat levels, green class drives typically have to sacrifice performance. This is primarily achieved through lower rotational speeds. In the case of the Caviar Green series, the rotational speed starts out around 5900rpm which is well below the standard 7200rpm rate. Now, Western Digital has implemented a variable speed system they call IntelliPower. This means that the drive will ramp up the rotational speed when the drive is having consistent usage. It then spins back down to the lower levels when idle to reduce the power and noise levels.

One key to note about the WD20EARS version of the drive is the Serial ATA interface. This drive uses the SATA II or 3.0Gbps interface speeds. Western Digital also makes a version that uses the new SATA III or 6.0Gbps interface. Why does this matter? Well, hard drive don't really require the faster interface as the mechanical properties restrict the overall performance of the drives. In fact, in testing, the highest burst rate of the drive was 176MB/s which is well below the 375MB/s maximum supported by SATA II. As a result, consumers can save a bit by going with this version over the WD20EARX or SATA III version.

As for the overall performance of the drive, it is actually quite good for a green class drive. As mentioned before, it can burst up to 176MB/s with average rates just below 100MB/s. The reason this can be achieved is the higher density of the drive platters on the Green drives compared to the faster drives with lower capacity. It still isn't going to load the OS, programs or data as quickly as a performance drive but it gets the job done. The best part is that the drive under heavy load runs very cool. This is great if the drive will be installed into an external enclosure or in a case that has limited airflow.

Overall, the best uses for the Caviar Green 2TB drive is as a secondary or backup drive. The high capacity will allow it to store a large amount of data. This is perfect for things like digital media files as they don't require the fastest read speeds in order to be properly utilized. Similarly, backups tend to be slowed down by the management and compression so it will work just as well as higher performance drives that cost more.

One important thing to note about the Caviar Green drives is that they are not suited for RAID usage. The reason is that the variable speeds of the drive can cause the multiple drives to become desynchronized that can lead to data corruption. So it is best to stick to lower capacity fixed speed drives if you want to create a high capacity drive array.

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Voyager spacecraft head for interstellar space

Artist concept of NASA's Voyager spacecraft (Image: NASA/JPL-Caltech)

The last time we checked on the Voyager 1 & 2 they were hurtling towards the edge of the solar system at over 37,000 mph (60,000 km/h). The car-sized spacecraft are now and incredible 11 billion miles (17 billion km) and 8 billion miles (14 billion km) from Earth respectively - they are the longest continuously operated spacecraft in deep space and, having traveled further than any man-made object, they will soon become the first to enter the realm of interstellar space. NASA recently held abriefing on the achievements of the program which gives us the opportunity to ponder where the Voyagers are, where they are going and the amazing scientific discoveries realized so far in their 33 year journey.

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Built by NASA's Jet Propulsion Laboratory in Pasadena, California, Voyager 2 was launched on Aug 20, 1977, closely followed by Voyager 1 on Sept 5. It was a special year because there was a rare planetary alignment of the outer planets, which meant the spacecraft would be able to visit all four giant gas planets; Jupiter, Saturn, Uranus and Neptune.

Flybys of Jupiter, Saturn, Uranus and Neptune

The Voyager twins' primary five year mission was to explore Jupiter (which was reached in 1979) and Saturn (1980). The spacecraft captured images of the planets, their larger moons and Saturn's rings, making some amazing discoveries. Jupiter's Red Spot was found to be a massive hurricane three times the diameter of Earth and just one of many huge storms on the planet. Saturn's rings were revealed to be made of a mish mash of icy particles - some as large as a house. Io, one of Jupiter's moons, was observed to have eight active volcanoes, where previously volcanic eruptions were only known on Earth.

Voyager 2, propelled further by Jupiter and Saturn's gravity, continued to Uranus in 1986 and Neptune in 1989. Breathtakingly close up pictures were taken of the planets, their moons and the system of rings and magnetic fields surrounding each. Notable discoveries included the fact that Uranus spins on a horizontal axis. Neptune the most remote giant planet has the fastest winds in the solar system that travel at over 1,200 mph (2,000 kph). Like Jupiter, it has a Great Dark Spot of its own, a giant storm about the size of Earth. Triton, a moon of Neptune is the coldest measured object in the Solar System. It has a surface temperature of -390°F (-235°C) with geysers spewing nitrogen gas into the atmosphere.

The Voyager spacecraft rewrote the textbooks on the four gas giants revealing the complexity and diversity of our solar system. On its way out of our solar system, Voyager 1 was asked to look back and take more photograph before the cameras were turned off. The "Pale Blue Dot" photograph was taken from a record distance of more than four billion miles from Earth and is part of the resulting is 60 frame mosaic of the solar system. In the photo, the Earth appears as a tiny dot 0.12 pixels in size, giving us a mind-boggling reminder of just how small we are in the vastness of space.

Still making discoveries and performing tricks

Voyager 1 will soon be the first probe to go outside our solar system. Using the gravitational force of Saturn and Jupiter, it swung North of the planetary plane and onwards to interstellar space. It is now over 117 times further from the Sun than we are and at this distance, the Sun is very dim - 1/10,000 as bright as it is here on Earth.

Voyager 2 is traveling at a slower speed, it is approximately 3 billion kilometers closer to us than Voyager 1 and heading south of the planetary plane.

The spacecraft is an incredible workhorse performing new tricks and old ones after long periods of time have passed. Voyager 1 was recently asked to perform a scan using its low energy charge particle instrument. This required a maneuver not performed since the Pale Blue Dot photograph was taken in 1990. The spacecraft was asked to rotate 70 degrees to scan data in three dimensions, hold for three to five hours and then swing back around to celestial lock.

Voyager 1 is currently in a type of "deadzone" called the heliosheath, a region where the solar wind is made turbulent by its interaction with the interstellar medium. The purpose of this scan, which will be repeated every three months, is to use the spacecraft's low energy charge particle instrument to determine when it passes beyond the very edge of our Sun's influence. Scientists believe that there are only a few more years of travel left before Voyager breaks free and can truly be called a traveler amongst the stars.

The signals traveling at the speed of light now take 13 hours one way to reach Earth from Voyager 2, and 16 hours one way from Voyager 1. To help put the distance into perspective; typical signals from Mars missions take 10 minutes one way. The signals are now so faint that they require the largest antennas on Earth to track them.

Equipment onboard Voyager

The Voyager spacecraft are identical. The size and weight of a small car, they are made up of a 10 sided main structure called the bus, a high-gain antenna, three booms that hold scientific instruments, the power supply and two other antennae. The main antenna is 12 feet (3.7 meters) across and looks like a satellite dish. This antenna is how the Voyagers receive commands from Earth and send data they gather back. No matter where a Voyager spacecraft is in space, the high gain antenna always points towards the Earth.

The spacecraft are powered by a radioisotope thermoelectric generator, in essence a nuclear battery. Pellets of plutonium release heat through natural decay and are converted into electricity using a series of thermocouples. It is a safe, reliable and long lasting power source expected to be finally depleted somewhere around 2025. Voyager's thrusters are fueled by hydrazine and there is enough on board to last another 60 years as fuel is only used to reorient the spacecraft. It uses about 1.6 grams per day.

Voyager carries various scientific instruments along with three computers that share just 68 KB of memory. Engineers developed a self repairing, programmable command processor with multiple modules that are able to determine errors by comparing past data.

The "Sounds of Earth"

The spacecraft are famous for carrying identical golden phonograph recordings titled the "Sounds of Earth." The records contain a cultural time capsule, images, natural sounds, spoken greetings in over 50 languages and musical selections from different cultures and eras. The gold plated copper records are 12 inches (30 cm) across and contain sounds and images selected to illustrate the diversity of life and culture on Earth. A gold plated aluminum cover etched with scientific hieroglyphics was designed to protect the records from micrometeorite bombardment. The cover shows an explanatory diagram on how to play the recordings and displays our cosmic address, illustrating the 16 closest pulsars along with an atomic clock explaining Voyager's launch date. The diagram appears on both the inner and outer surfaces of the cover because the outer diagram will be eroded in time.

The records should not to be confused with the simpler metal plaques on Pioneers 10 and 11 which were launched in 1972. The plaques were designed to show scientifically minded extraterrestrials when Pioneer was launched, from where and by whom. They present amongst other things, a male raising his right hand in a gesture of goodwill.

A "Noah's Ark of human culture"

The golden records were a much more ambitious message than the Pioneer plaques, created as a "Noah's Ark of human culture". Over 100 pictures illustrating Earth were collated, each like a tile in a large mosaic of life on Earth. They present people doing mundane activities such as eating and drinking as well as showing our anatomy and DNA structures. Plants and animals are included along with scenes from around the world such as a Thai craftsman, a gymnast and a schoolroom. Various landmarks including the Golden Gate Bridge, the Sydney Opera House, the Great Wall of China, the Taj Mahal and UN buildings are also documented.

Over 90 minutes of recordings are included ranging from storms and volcanoes to human made sounds like a mother kissing her child and rocket takeoffs. Greetings in over 50 different languages and 27 pieces of music including Beethoven, Bach, Mozart, world music from China, Japan, India and Peru. There's also a rock'n'roll track - "Johnny B Good" by Chuck Berry (not the Rolling Stones as falsely shown in the movie Starman).

The future of Voyager

Once outside the heliosphere, Voyager 1 will take measurements of the vast clouds that envelope our solar system. These clouds are remnants of stars that exploded five to ten million years ago. NASA hopes to operate Voyager until 2025 when it will then be left to wander throughout the galaxy for another 1000 million years.

The spacecraft are still functioning and thriving after more than 30 years. Robust, durable and built from 1970s components, the transistors are still functioning today. They have exceeded their design specifications and the loftiest dreams of their makers ... and despite having already made an amazing contribution to our civilization, many great discoveries are still to come.

Voyager 1 is on a trajectory to reach star AC+79 in about 40000 years. Voyager 2 is on its way to the vicinity of star Sirius, a mere 296,000 years away.

You can keep up to date with how far the Voyagers are from home with NASA's real-time odometer.

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