Looking back: 2004

In 2004, I was privileged to visit Middle Earth (aka New Zealand) with a colleague and to present the paper “Network Robustness and Graph Topology.” A major event of that year was the landing of the Mars rovers Spirit and Opportunity. Intended to operate for 90 Martian days (92 Earth days), Spirit kept going until 2010 (as xkcd remarked on in the comic above) and Opportunity set a record by operating until 2018. Also in 2004, the Stardust spaceprobe collected some comet dust.

On a more sombre note, 2004 saw the Boxing Day Tsunami. In the field of technology, Facebook and Gmail both launched in 2004, and Vint Cerf and Bob Kahn shared the Turing Award (for having invented the Internet).

This was an excellent year for cinema. Examples from different genres include National Treasure, Troy, Van Helsing, Man on Fire, Hotel Rwanda, The Village, Howl’s Moving Castle, and The Passion of the Christ. I certainly have memories that I treasure.

In this series: 1978, 1980, 1982, 1984, 1989, 1991, 1994, 2000, 2004, 2006.


InSight mission to Mars launches on schedule

The InSight Mars lander launched yesterday from Vandenberg Air Force Base in California, and is scheduled to land on Mars on 26 November. There, it will probe beneath the surface and check for “marsquakes.”

Follow the progress of the mission here.


The InSight lander (JPL/NASA image)


Spaceprobes in the Solar System

The diagram above (click to zoom) and list below show currently active spacecraft in the Solar System, not including those operating close to the Earth (and I’ve probably missed a few):

  • Voyager 1 and Voyager 2, launched in 1977, now heading into the darkness and still reporting back, even though they are over 17 billion km or 16 light-hours away (not shown above).
  • Cassini–Huygens, launched in 1997, now in the final stages of its exploration of Saturn (see fact sheet).
  • 2001 Mars Odyssey, launched in 2001, and still orbiting Mars.
  • New Horizons, launched in 2006, now en route from Pluto to the Kuiper belt object 2014 MU69, which it should reach in January 2019.
  • Dawn, launched in 2007, currently orbiting Ceres (image shown above the Earth).
  • Akatsuki, launched in 2010, currently orbiting Venus, which it will do until 2018.
  • Juno, launched in 2011, currently orbiting Jupiter, which it will do until February 2018.
  • Hayabusa 2, launched in 2014, currently en route to asteroid 162173 Ryugu, which it should reach in 2018. It will then take a sample which should arrive back home in 2020 (not shown above).
  • ExoMars Trace Gas Orbiter, launched in 2016, currently orbiting Mars and mapping the Martian atmosphere (the associated Mars lander was lost in 2016).
  • OSIRIS-REx, launched in 2016, currently en route to asteroid 101955 Bennu, which it should reach in 2018. It will then take a sample which should arrive back home in 2023 (image shown below the Earth).

In addition to the above, BepiColombo is scheduled to launch for Mercury in October 2018, and SolO is scheduled to launch for the Sun that same month. Also, InSight is scheduled to launch for Mars in May 2018, and Solar Probe Plus is scheduled to launch for the Sun in August 2018.


The ExoMars lander

The ESA/RFSA ExoMars lander seems to have crashed on Mars, unfortunately. The chart above shows the planned sequence of events (which was to have ended with a soft collision). Instead, we seem to have had an early parachute release, with a very brief use of thrusters, followed by loss of signal after 19 seconds – consistent with free-fall to the surface under Martian gravity.

Update: the crash site seems to have been identified.


Mars in the Night Sky

Mars is growing brighter in the sky, appearing close to the star Antares and the planet Saturn (see NASA image above). Later this month, Mars will reach the point of closest approach, and hence largest apparent size.

For the current distance to Mars, see Wolfram’s calculator or the live diagram of the solar system at Fourmilab, which includes images (green lines show orbits below the plane of the ecliptic):

Live Solar System image


Surface areas of the solar system

Here is another gem from XKCD: surface areas of the various solid objects in the solar system – excluding the gasballs Jupiter, Saturn, Uranus, and Neptune, but including their moons (click to zoom). As might be expected from images of the planets, Earth and Venus have the lion’s share of the real estate:

Mars gets closer and brighter…

On April 8, the planet Mars was in opposition. That is, Mars was on the opposite side of the sky to the Sun. Also, on April 14, Mars will be at the closest point to Earth in its orbit (92 million km). A great time to observe the “red planet”!

This video from Slooh explains various aspects of the planet at length:

For the current distance to Mars, see Wolfram’s calculator or the live diagram of the solar system at Fourmilab, which includes images (green lines show orbits below the plane of the ecliptic):

Live Solar System image