Category Archives: Satellites

Your Universe, October 2013

Gleb demonstrates the use of a spectroscope
For three days in early October, the South Cloisters and Garden Room of UCL played host to a festival of astronomy – Your Universe. Organised by Francisco Diego and Farah Islam from the department of Physics and Astronomy, the event was divided into two school days and one Saturday for the general public. The events saw demonstrations and explanations of different aspects of astronomy delivered by researchers in the department as well as two lectures, one each on Friday and Saturday evening.
Organisor, Francisco Diego
The quiet and darkness of the Garden Room saw three presentations. The first was a powerpoint presentation on exoplanets – planets orbiting stars other than our Sun – delivered by David Johnson. The second was the Magic Planet, a globe onto whose inner surface was projected the atmosphere or outer surface of the Sun, several planets and satellites in turn. Finally, a demonstration of spectroscopy and the fingerprints of colours emitted and absorbed by individual elements was given by Gleb with lamps and spectroscopes capable of splitting light into the rainbow of available colours.
Exoplanets, starting closer to home
Our Magic Planet
Atomic spectroscopy
In the South Cloisters, another five demonstrations lay in wait. Firstly Emily Hall expanded minds with a talk on cosmology, discussing Dark Matter, that mysterious thing that interacts only gravitationally with normal matter, and Dark Energy; the curious driving force behind the expansion of the universe. Next came a demonstration of robotic telescopes controlled over the internet from a NASA and Harvard maintained website. The third talk took in the life cycle of stars and an explanation of the HR diagram that astronomers use to categorise stars. The fourth demonstration was telescopes, including scopes either looking at the Sun in the light of hydrogen atoms or, during less clement weather, at postcards at the other end of the South Cloisters, and a display on the University of London Observatory, used by UCL students studying astronomy. Finally, a demonstration of the timescales involved in the creation of life and the universe rounded off the main set of events.
The Dark side of the Universe
Welcome to the MicroObservatory
Discussing the life cycle of stars
An intro to ULO
One of our display telescopes
The Sun in Hydrogen Alpha light
13.8 billion years of history on seven boards
Outside of the main event, more sedate displays in the Octagon and North cloisters were within easy reach of guests. These included an orrery, showing the motions of planets and major satellites around the Sun and a book of satellite images open at plates showing the Earth and Moon as seen by Lunar Orbiter 5. In the North Cloisters, the entire length of the space had been taken up by Pete Grindrod’s display; a high resolution image, ten miles of the surface of Mars as seen by the HiRISE camera on the MRO satellite, presently in orbit of the Red Planet.
Orrery in the Octagon
Lunar Orbiter 5 images
Ten miles of Mars
Five miles of Mars
Another five miles of Mars
Scale
With eight groups of primary and eight secondary age pupils per day, we saw around five hundred school children pass through the displays during the first two days and more than another hundred members of the public on Saturday. They also enjoyed two lectures; Mikako Matsuura’s description of seeing star birth through the eyes of the Herschel infrared space telescope and Francisco Diego’s answer to the question of why have we not found evidence of aliens.

Further pictures can be found here.

The skies over Kendal in October

We’re moving into the darker, colder and usually rather cloudy nights of the end of the year. As ever, this post is illustrated with a few sky charts showing midnight on the first, last and fifteenth day of the month. The dots represent brighter stars, green circles are star clusters, nebulae, galaxies and the like and the very brightest stars, the Moon and the planets are named when they appear. Sky charts provided using Stellarium.

Solar system

The Moon will be in the last quarter phase on the 1st, new on the 7th, first quarter on the 14th and full on the 23rd. On the 14th, the Moon will occult the star 50 Sagittarii at around 8:10pm for northern observers.

The middle of the month sees the start of the Orionid meteor shower, which will peak on the 21st. Peak rates are low and a full Moon will blot out all but the brightest. Orionids are fast and leave persistent trails. They are best seen before dawn.

Heavens above presently lists two comets above magnitude 12 and seven asteroids above magnitude 10 in the hours of darkness. The comets are: 103P Hartley at 5.6 – approaching visibility – in Cassiopeia and 10P Tempel 2 at 10.1 in Cetus. Details on the future movements and changing brightness of the comets can be found here. The asteroids are 6 Hebe at 7.8 in Cetus; 4 Vesta at 7.9 in Virgo; 8 Flora at 8.6 in Aquarius; 1 Ceres at 8.9 in Sagittarius; 7 Iris at 9.4 in Gemini; 39 Laetitia at 9.5 in Aquarius and 471 Papagena at 9.8 in Cetus – rather a busy constellation this month.

The Planets

Mars is usually lost in atmospheric haze now. It shines at +1.5, appearing in the south-west, only to set an hour after the Sun.

Venus is seen just below Mars as the Sun sets, shining much brighter, but also lower, requiring a very low horizon to the West to see it.

Mercury for the next day or two, Mercury is visible in the Eastern horizon shortly before the Sun rises, though it will appear dimmer than its +1.3 magnitude suggests due to the bright sky around it.

Saturn returns to the skies at the end of the month, making an appearance shortly before dawn with rings now angled such that they look more like rings. The planet will shine at a magnitude of 0.7.

Jupiter continues to shine brightly as ‘that star in the East’. It shines at a magnitude of -2.9 and is in an empty part of the sky. Its inclination is such that transits of satellites happen quite a bit. Times of some of these and appearances of the Great Red Spot are here.

Uranus lies a couple of degrees west of Jupiter, plus a little above, and shines at 5.7.

Neptune is also in the morning skies, on the border of Capricorn and Aquarius.

A few things outside the solar system

The constellations of Leo, Virgo and the Big Dipper are all home to galaxies, details here. This is not a good month to look at faint things as the all-night twilight obliterates detail and contrast.

The Usual Stuff

If you want to watch satellites flaring or passing in the sky (even sometimes during the day), then go to Heavens Above to get times and directions. If you need assistance in deciding where things are in the sky, why not install the free program Stellarium, which does all the work for you? Finally, to avoid the dreaded clouds, Met Check gives a quick forecast and the Met satellites or other satellites can be used to track breaks in the cloud. For an indication of auroral or solar activity, SpaceWeather.com is an invaluable resource. If the stars aren’t available, there’s always solar astronomy. Projections of the Sun onto white card can show sunspots, when properly focused. A good filter (not an eyepiece filter) or a dedicated solar telescope will show better details. Never observe the Sun without filters and never with an inadequate, inappropriate or old (and therefore possibly with holes in) filter.

Public events

For young astronomers (ages 9-16) Space Explorers is run in Kendal Museum on the third Saturday of most months from 2:30-4:00 pm. The next meeting is on Saturday the 23rd. The Society for Popular Astronomy also has a sky map for young astronomers here.

Plus why not pop along to the Eddington Society, which meets at Kendal Museum on the first Monday of each month, this month it is on the 4th, with member’s projects the subject of the meeting. There will also be a public observing event at The Brewery Arts Centre on the 15th from 6:30pm.

Don’t forget to check back here and on my twitter account for the latest astronomical events in this area.

Satellite launch problems

The $424 million Glory mission to study the impact of aerosols on climate variability has been delayed due to problems with the mechanisms operating its solar panels. Originally slated for a 22nd of November launch, it has now been pushed back to the 23rd of February to allow time to correct the problem. This will mean the satellite will launch almost a year after the same rocket type exploded, destroying another climate satellite.

Meanwhile, hot on the heels of the announcement of launch dates closing in for the human spaceflight aspect of Virgin Galactic, it appears the satellite launch part of the business is being allowed to slide for the time being, with its head departing and no replacement currently in sight. Branson talked up the utility of satellite launches for the education sector in his recent press event, but more as a speculative venture.

Some spaceflight stuff

There’s a lot of activity in the space sector at the minute in anticipation of the ending of one era and the start of another.

The end of the Hayabusa asteroid sample return mission will have to wait a little longer. Although the Japanese satellite made it back from the asteroid, got its canister back to Earth and the scientists recovered it and have identified particles inside the first collection chamber, the results of analysis of the particles are not likely until February or March next year.

The start of the third and final era of the Cassini mission. The satellite entered Saturn orbit in 2004 and conducted its four year mission with few problems. Since 2008, it has been running the Equinox mission extension. Now that has run out and the satellite has begun the seven year Solstice mission, which should see it to a spectacular end in the clouds of the ringed gas giant.

The Interstellar Boundary Explorer, or IBEX space telescope studies an unusual target. Rather than gathering light like an ordinary telescope, it looks at particles. In particular, it studies neutral particles created by the collision of the solar wind outflow from the Sun with the material between the stars. Last year, it saw the image of a ribbon in space, interpreted as a magnetic flux tube. Further studies in the intervening time have shown this pattern to be altering on the six month timescale of the new observations. The ribbon is becoming a simpler pattern, with fewer loops and twists. This is rather faster than the eleven year solar activity cycle impacting on a uniform medium would suggest, giving us an interesting glimpse of what is happening out there. Details are reported here and here.

CryoSat is a satellite at the start of its life. The polar explorer is presently in orbit gaining data on the thickness of ice around the globe. That data needs to be calibrated and validated before full operations can go ahead. The commissioning phase will be completed in mid-October, but further validation will be required and will have to be done on the job. A validation workshop will therefore be held in ESA/ESRIN in Frascati (Rome), Italy from the 1st – 3rd February 2011. Details and flyer here.

Another satellite even earlier in its life is China’s latest Lunar satellite, Chang’e-2, which blasted off on a Long March 3C rocket earlier today (1st of October) – video here. The satellite, the second of China’s lunar program, is set to arrive in orbit in around five days and is being tracked by China with the help of ESA. The probe’s spaceframe was created as a spare for the first lunar probe, but rather than create an entirely new probe for the second mission, researchers pinned the new technology onto the old spaceframe. The probe includes a laser altimeter, a CCD camera and an impacter. It is designed to gather data for future missions and test key technologies. The next lunar mission is aiming to put a rover on the lunar surface and eventually the program hopes to put a man on the Moon.

From launched missions to scheduled to launch missions. The updated manifest for the final launch of the space shuttle and construction of the International Space Station has been announced. ESA plans the launch of ATV2 on the 15th of February, with NASA launching the final shuttle mission, STS-134, on the 27th of February. Roscosmos is looking into extra Soyuz launch and landing slots to add capacity if needed. Meanwhile, STS-133 still has to be launched and the 1st of November mission will be previewed in a press conference on the 21st of October. Details here.

Also set to blast off in November, the Hylas-1 satellite has been undergoing tests in India and is now set to be shipped to the launch pad in French Guiana, ESA’s spaceport ArianeSpace. The satellite is a public-private partnership between ESA and Avanti Communications to provide broadband capacity to customers in the EU, part of the EU’s commitment to universal 25mps broadband by 2025. The spaceframe has been purchased from India with Avanti providing the communications technology.

Some satellites aren’t yet scheduled for launch, but need to be shipped here and there to get them tested and together. Three different space telescopes are presently at different stages of this process. The LISA pathfinder mission, which will test the technologies to be deployed on the LISA gravitational wave observatory, has spent the summer having its electromagnetic fields and responses tested and checked. LISA will use precisely controlled spacecraft to hunt for the tiniest variations in position and as such need an extremely high level of knowledge about where each part of the spacecraft is and what it is doing. Parts of the spacecraft have also undergone thermal testing to see how the proximity and direction of the Sun will alter the spaceframe. Meanwhile MIRI, the Mid InfraRed Instrument, of the James Webb Space Telescope, a massive venture that will act as a Hubble Space Telescope equivalent in the infrared, has arrived at the Rutherford Appleton Laboratory for pressure testing. Finally, the Mechanical Service Module, which will act as the control system for the Gaia space telescope, which will perform precise astrometry, measuring the positions and motions of a billion stars in the Milky Way, has been put together. The thing now needs integrating with other parts that are scattered across the globe in various stages of construction and testing.

Onto future spacecraft and ESA has been asked to make a decision. Presently, it has the use of the ATV (Automatic Transfer Vehicle), an automated vehicle that can deliver stuff to the ISS, but then gets burnt up on reentry. A new vehicle, the ARV (Automatic Reusable Vehicle) has been proposed, which replaces the cargo module on the front of the ATV with a reentry capsule and also upgrades the service module. This would enable things to be returned from the ISS to the ground – such as science experiments and the like. However, there is some opposition to the craft, which some say has no future as the ATV is seemingly adequate for the jobs required of it and development of the ARV to full production capacity would probably leave little time before the ISS is decommissioned and the vehicle needing a new mission.

One possible new mission could be the development of private space hotels. There’s been a few proposals and actual launched vehicles from the USA, but now a consortium in Russia has announced plans to put up a space station. The CSS, or Commercial Space Station, will provide space for up to seven people (one commander and six non professionals) performing commercial research or just lounging about. The four room guesthouse will be supplied by Russian Soyuz and Progress spacecraft, taking advantage of the lack of alternatives in getting people into space and Russia’s enhanced relative capabilities when others around do start popping up with new launch vehicles – all of which will also be able to partner with the station. Orbital Technologies has teamed up with a state run company and the Russian space agency to make the project a reality. The station is, unlike the ISS’s modular creation, expected to be launched on a single rocket. Construction is expected in 2012 or 2013.

Meanwhile, SpaceShipTwo, the space tourism craft operated by Virgin Galactic, has been built and is expected to begin operations in around eighteen months. Sir Richard Branson’s sights are also turning toward providing commercial satellites for the education sector as well as potentially space hotels (getting crowded up there…) and eventually a lunar habitat.

Surrey Satellite Technologies Limited has announced three Earth Observation satellites, costing £100 million are to be built and launched in 2013 to provide data commercially as well as a £10 million satellite construction and testing facility in Guildford.

Now onto conceptual spacecraft and one NASA plan to create a heavy lifting spacecraft from modified shuttle boosters, fuel tanks and engines has been obtained by a website. At present, NASA works on the Ares rocket, derived from the solid rocket boosters that appear at the sides of the big orange fuel tanks that supply the stuff that the shuttles burn to get into orbit. This new design would lose the shuttle, move the engines from the orbiter to the fuel tank and stick a capsule on top, with some other frills. A power system has been developed that would see energy taken from the solar wind. The satellite has the capability of taking charge from the stream of ions and electrons that constantly whiz from the Sun to the outer regions of the solar system, but at present there’s no way to transfer the power back to Earth or any passing spacecraft that could use it.

And for some words on the future of spaceflight from those in whose hands it may potentially lie, the head of the UK Space Agency has been giving his view in an interview, as has the Director General of ESA.

ISS crewmembers land successfully

Three crewmembers from the International Space Station have successfully undocked from the station and landed in Kazakhstan in vehicle Soyuz TMA-18. The event brings to an end the crew configuration known as Expedition 24. The new crew configuration, Expedition 25, will commence when three new crewmembers join the three still on the station. This is expected to happen on the 9th of October, with the arrival of Soyuz TMA-01M.

The Soyuz undocked at 03:02 BST today. It carried out a separation burn to put distance between it and the station. At 05:31, it performed a four minute twenty one second deorbital burn, slowing it down sufficiently to drop out of the skies. The three segments of the vehicle separated at 05:56 and the crew continued towards the ground in the descent module, which entered the atmosphere at 05:59. It landed near Arkalyk, in Northern Kazakhstan, at 06:23. Pictures like the one shown below are at NASA’s flickr photo stream:

Events were also captured on NASA TV and archived to their youtube channel, from which the following, showing the change of command, the aborted landing, farewells and the actual undocking and landing, were taken:

More on Saturn’s aurora

Following Tom Stallard’s EPSC 2010 presentation on videos of the changes in Saturn’s aurora (including faint auroral signals) and linking that to events in the magnetosphere in general, there’s been a couple of news items in magazines. New Scientist managed to get the wrong end of the stick, believing the infrared aurora to be the new thing (it isn’t, just the video of it and the faintness of the signal) whereas Astronomy Now gave a more proper writeup, including a genuinely new thing from the same session on the detection of Saturn’s radio aurora. Radio emissions come from charged particles getting deflected by magnetic fields, which is what happens when auroral particles head to the auroral regions of a planet. Satellites have long been able to put themselves in the thin zone of emissions from Earth, Jovian observers have detected the Io current associated auroral radio signals, but Saturn has been more elusive to satellites in its region until now.

Soyuz landing tonight

This post might seem like a repeat…

Last night’s undocking of the Soyuz vehicle that would bring three astronauts back to the ground was halted after ground control in Moscow received a signal suggesting the International Space Station had not been made airtight as the hatches between the two vehicles closed. Once this had been resolved, the vehicle refused to unhook itself from the ISS when the command was given, so the undocking was cancelled and repairs carried out.

Now the three crewmembers are sat back in the vehicle. The hatches are closed and everything’s registering as airtight. Undocking is expected at 3:02 am BST and landing at 6:22 am BST, all broadcast on NASA TV, if this time it happens…

The replacement crewmembers are expected on October 9th.

Soyuz crew drop to take place soon

A trio of astronauts from the International Space Station are preparing to take an elevator ride they’ll never forget. They are presently sitting in a Soyuz capsule waiting for the OK to decouple and head off towards Earth. A problem with the couplings has delayed things for a while, but undocking burn is expected at 00:40 EDT (5:40 BST), deorbital burn at 3:14 EDT (8:14 BST) and landing north of Arkalyk around 4:05 EDT (9:05 BST). Coverage on NASA TV will resume at midnight EDT (5am BST).

Space probe roundup

There’s a few probes out there, gathering data in the solar system, so starting from the inner planets, today’s news includes:

Venus Express has been watching a vortex playing in the atmosphere above the south pole of Venus. In 1979, the Pioneer Venus mission spotted a vortex above the north pole and on arrival in 2006, Venus Express found its southern twin. However, continuous recording of the phenomenon has shown that the double-eyed appearance of the vortex was simply a coincidence. Other vortices have since come and gone at the south, leaving the double eyed feature nowhere to be found. Full details are here.

Sticking with Venus Express, but delving lower into the atmosphere, lightning discharges on the second planet from the Sun have been confirmed as happening as frequently on Venus – one hundred times a day – as on Earth. The storms are strongest on the dayside, where the Sun provides the energy for cloud particles to collide and rub together, and also strongest towards the equator, for the same reason. The signals, previous detected by other probes using different instrumentation, were detected using Venus Express’s magnetometer and were apparent from the earliest times after insertion into orbit. Full details here.

Onto Earth now and a crater seen in satellite images bundled into the Google Earth software has been confirmed as being an impact feature. The feature was spotted in 2008 in images of the Egyptian desert and has been measured at 45 metres diameter and 16m deep. The crater was forged by the impact of a 1.3m meteorite weighing in at 10 tonnes (one tonne of which has now been collected up) sometime in the last several thousand years. The crater has evaded the geological processes that tend to erode such features and seems to have also escaped notice from human eyes in all that time. More on the discovery and confirmation of Kamil crater (including a google maps page showing the thing) can be seen here.

Three years of data from the SMART-1 mission to look at the Moon have been released by ESA. The three scientific instruments on board the probe were: the Advanced Moon micro-Imager Experiment (AMIE), which was a camera in visible and near infrared light, which watched the terrain changing as the shadows changed and so mapped the southern pole of the Moon to a resolution of 40m per pixel; the SMART-1 InfraRed Spectrometer (SIR), which watched the spectrum of the Moon in the 0.9-2.6 micrometer wavelength range, enabling mapping of pyroxene and olivine in solidified lunar magma exposed by asteroid impacts; the Demonstration of a Compact Imaging X-ray Spectrometer (D-CIXS), which mapped the Moon in the 0.5-10keV photon energy range, enabling x-ray reflection spectroscopy of some heavy elements. Fortunately for D-CIXS, a high energy solar flare provided additional x-ray flux enabling some of the elements that would normally be producing very dim signals to shine brightly enough to be confirmed. The data can be found here.

Further out and Mars Express has been used to examine the unusual behaviour of carbon dioxide ice in the Martian polar cap. Observations of the ice showed unusual behaviour as the cap receded in warmer times. The signal of the CO2 is seen to weaken and vanish as it sublimates from ice to gas, but then not long after, the signal suddenly returns before vanishing again. This fade in, it was hypothesised, could be due to a protective layer of dust or water ice protecting the underlying CO2. As there was no change in brightness, as there would be if white ice gave way to dark dust, researchers concluded water ice, invisible to the instruments they were using, must be the insulating layer. The Martian polar caps contain a mixture of water ice and CO2 ice. CO2 sublimates at a lower temperature, so what was happening was the exposed CO2 vanished, leaving a water ice shell (added to by condensing water ice from warmer, lower latitudes) and underlying CO2. Then there came the problem of why the water ice was suddenly stripped away revealing lots of CO2 to provide the second signal. Models of downward flowing winds created by the warming showed that these were capable of doing the stripping, lending the final piece of the theory. Full details here.

The Rosetta probe is set for a date with the Comet 67P/Churyumov-Gerasimenko in May 2014. Computer models of the three dimensional shape and motion of the comet have been used to assess what part of it will be least prone to outgassing as the block of rock and ice closes in on the Sun. The results suggest the southern hemisphere will be the best place for Philae, the lander delivered by the probe, to hook on and sample the comet material. Before the probe meets the comet, this hemisphere will receive the largest amount of sunshine, eroding the outer crust and exposing pristine material within. By the time the probe meets the comet, and after delivery of the lander, the north pole of the comet will be in the glare of the Sun, and so most prone to outbursts. The lander will use harpoons and jets to hook onto the comet during its studies. Full details here.

Cassini will be performing the first in a series of Titan flybys over the next eighteen months later today. The aim will be to supplement climate studies of the distant satellite of Saturn, more details here.

Cassini has also been taking a good look at the parent body in the infrared. Using the Visual and Infrared Mapping Spectrometer, Tom Stallard of Leicester (and formerly UCL) has been observing changes in the southern lights of Saturn to compare with other processes going on in Saturn’s magnetosphere, the aim being to connect the two. The aurora of Saturn are complex and involve both large scale motions of the magnetosphere – contractions and expansions caused by the uneven passage of the pulsed solar wind – and small scale structure such as disruption of particle and energy flows by the moons of Saturn inside the magnetosphere. More details of his infrared work are here and some images of ultraviolet auroral signals from Saturn and Jupiter by the Hubble Space Telescope are here.

Big astronautics conference soon

The 61st International Astronautical Congress (IAC) will be held in Prague, the Czech Republic from the 27th September until the 1st October under the theme of Space for Human Benefit and Exploration. This gathering of 3,000 top spaceflight experts is drawn from the space agencies, industry and academia. There will be a media day as well as chances for younger researchers to meet with the top brass of the field. ESA will also be putting on an exhibition on the theme of Space for Earth.

Details here.