late July and early August mark the period of the 2020 Mars opposition launch window, once again offering opportunities to send missions to the Red Planet. This period occurs once every 26 months, when the orbits of Earth and Mars are both on the same side of the Sun (so Mars and the Sun are on “opposite sides” of Earth, hence the name “opposition”) and positioned relative to one another (with Earth “catching up” with Mars as they both move around the Sun) such that the flight time from Earth to Mars is at its shortest – around 6-7 months.
Because of this, these periods tend to be fairly busy, and 2020 is particularly so, with three missions heading for Mars. The most prominent of this missions in terms of publicity is NASA’s Mars 2020 Perseverance rover, scheduled for a July 30th 2020 launch. The second is China’s ground-breaking orbiter / lander / rover mission (of which more below), whilst the third – and first to launch – is possibly the most overlooked of the three: the Hope, or Al-Amal, orbiter mission developed by the United Arab Emirates.
Hope is a remarkable mission for the UAE; the mission was announced in 2014, literally as the country formed its fledgling space agency, employing just 75 people – a number that has since grown to 150. At that time the UAE had developed and flown – in partnership with other nations – a total of 5 communications satellites and two Earth observation platforms, so the idea for the country’s new space agency setting its sights on Mars was seen as incredibly ambitious.
However, over the course of the last six years the United Arab Emirates Space Agency (UAESA) has worked steadily on the the project, and has drawn on space development expertise in France, Japan, the UK and USA both for its own development and for the Hope spacecraft, moving the project forward and at minimum cost – just US $200 million.
Roughly cubic in shape, Hope measures 2.37m wide and 2.90m in length and has a mass of just under 1.4 tonnes (including its propellant fuel load). Solar-powered, it is billed as the “first true weather satellite for Mars” and is intended to develop a complete picture of the Martian atmosphere.
To do this, the satellite has a primary mission period of a full Martian year (approx. two terrestrial years), with the option for mission extensions through to 2025. During this time, the spacecraft will study the Martian climate and weather on a daily basis from a 55-hour equatorial orbit around the planet that will vary between 20,000 and 43,000 km from the planet’s surface. This high orbit will afford it the best view of weather patterns in both the northern and southern hemispheres, and observe how weather patterns interact along the equatorial regions of the planet. In particular, Hope will be able to study seasonal weather / climate cycles and record weather events in the lower atmosphere such as dust storms, and the weather at different geographic areas of Mars.
To achieve this, the mission carries a relatively modest number of science packages compared to other missions, comprising:
- The Emirates eXploration Imager (EXI): developed with assistance from two US research facilities, this is a multi-band camera capable of taking high resolution images with a spatial resolution of better than 8 km. Equipped with a set of 6 filters, it can image in both RGB colour wavelengths and in the ultraviolet bands, and measure properties such as water, ice, dust, aerosols and abundance of ozone in the Martian atmosphere.
- Emirates Mars Infra-red Spectrometer: developed with the assistance of the Arizona State University, this is an interferometric thermal infra-red spectrometer. It is designed to examine temperature profiles in the Martian atmosphere and record ice, water vapour and dust in the lower to mid-level of the atmosphere.
- Emirates Mars Ultraviolet Spectrometer (EMUS): is a far-ultraviolet imaging spectrograph for measuring global characteristics and variability of the Martian thermosphere.
As well as carrying out a genuine science mission that will produce data that will be of significant use for future missions up to and including eventually sending human to Mars, Hope is also seen as an inspirational programme intended to “send a message of optimism to millions of young Arabs” and encourage them to consider careers in science, technology, engineering and maths (STEM).
Nor, given the traditional conservative nature of Arab nations, is this inspirational element of the mission directed solely at young men: the deputy project manager and lead science investigator for the mission is Sarah Amiri, who is also is the Chair of the United Arab Emirates Council of Scientists. She has managed the mission’s objectives and overseen the development and integration of the mission’s science packages, and and will continue in that role throughout the mission. Her role is seen as pivotal to encouraging other Arab nations in allowing women greater access to leadership roles and in encouraging young Arab women to consider STEM-based studies and careers.
As the UAE does not have its own launch capability, UAESA partnered with JAXA, the Japanese space exploration agency to launch Hope atop a Japanese H-IIA rocket from the Tanegashima Space Centre. The H-IIA is one of the most reliable launch vehicles currently operating, having entered service in 2001, and capable of delivering up to 6 tonnes to geostationary orbit. It is a highly reliable vehicle, having suffered only one failure in its 190-year career.
The initial launch opportunities had to be abandoned due to inclement weather, the launch window having opened on July 14th, causing a further opportunity to be marked for Sunday, July 19th.
This launch opportunity brought with it almost perfect weather, and the countdown proceeded flawlessly so that at 21:58 GMT (01:58 in the UAE on Monday, July 20th), the H-IIA’s motors ignited, and the vehicle lifted off the pad at the space centre, located on the south-east coast of Tanegashima, an island approximately 40 km south of Kyushu. Some two minutes into the flight, the rocket’s booster motors were jettisoned, allowing the core of the booster continue to orbit, where the upper stage separated and the payload shrouds were also jettisoned.
Following a 45-minute orbit around the Earth, the H-IIA’s upper stage motor ignited, accelerating the vehicle away from Earth into into a trans-Mars injection orbit around the Sun. The flight to Mars will cover distance of 493.5 million km, with the vehicle reaching a maximum cruising speed of 121,00 km/h. It will arrive in Mars orbit in February 2021, and is seen as a part of the country’s 50th anniversary celebrations.
I’ll have a further update on the mission in the next Space Sunday piece.
China Readies Tianwen-1 for Mars Launch
As noted above – and previously reported in past Space Sunday reports (see: China’s missions and a disappearing “planet”) – China also hopes to join the “Mars club” through its even more ambitious Tianwen-1 (“Quest for Heavenly Truth”) mission comprising an orbiter, lander and rover.
The mission will mark the first time a combination of orbiter + lander/rover have been flown to Mars on in single mission. The overall goal for Tianwen-1 is to seek evidence of current or previous microbial life, and evaluate the planet’s surface and environment. Once in place, the orbiter and rover will operate both individually and in tandem, exploring Martian surface topography, obtaining data on soil characteristics, material composition, water ice, atmospheric composition, and ionosphere field intensity, using a total of 12 instruments, several of which have been developed in partnership with the European Space Agency and the French National space Centre, CNES:
- Medium Resolution Camera (MRC) with a resolution of 100m from a 400 km orbit.
- High Resolution Camera (HRC) with a resolution of 2m from a 400 km orbit.
- Mars Magnetometer (MM).
- Mars Mineral Spectrometer (MMS), to determine elementary composition.
- Orbiter Subsurface Radar (OSR).
- Mars Ion and Neutral Particle Analyser (MINPA).
- Ground-Penetrating Radar (GPR), to image about 100 metres (330 ft) below the Martian surface.
- Mars Surface Magnetic Field Detector (MSMFD).
- Mars Meteorological Measurement Instrument (MMMI).
- Mars Surface Compound Detector (MSCD).
- Multi-Spectrum Camera (MSC).
- Navigation and Topography Camera (NTC).
As with their approach to many things, the Chinese generally don’t say too much in detail about their space missions, but on July 17th, and covered by a live broadcast by state television, the Long March 5 launch vehicle that will send Tianwen-1 on its way to Mars was rolled-out to the launch facilities at the Wenchang Satellite Launch Centre. Designated Long March 5-Y4 (the Y4 denoting the 4th launch of the Long March 5 vehicle, although there has also been a single launch of the Long March 5B as well), it is estimated that the roll-out means that Tianwan-1 could lift-off on July 23rd, given that previous Long March 5 missions have generally seen a 6-day pad check-out period between roll-out and launch.
Assuming the launch is successful, Tainwen-1 will also arrive in Mars orbit in February 2021. Once there, the combined orbiter / lander will remain in orbit for a period of around 2-3 months whilst the landing zone for the latter is fully reconnoitred, prior to the landing attempt being made.
Once on the surface of Mars, the rover will likely be deployed from its lander fairly quickly. While classified a Yutu-class vehicle (the type of vehicle China has twice successfully deployed on the Moon), the 240 kg rover weighs twice as much as its lunar cousins. Solar-powered, the rover is expected to operate for an initial three months, whilst the orbiter has an initial primary mission of one Martian year.
Should the launch go ahead this week, I’ll have a further update in my next Space Sunday report.
Still Time to See NEOWISE
In my July 12th Space Sunday article I wrote about comet NEOWISE, a long-period comet with a solar orbit of (now) 6,800 years, that is about to make its closest approach to Earth (on July 23rd). While there were concerns the tails of the comet might fade over the course of the last week, it remains a bright object that can be see in northern hemisphere night skies during twilight (around 80 minutes after local sunset) to the North-east, slightly to the left of the Plough, and over the course of the week there have some spectacular photos taken of it.
The comet is best seen via binoculars (a telescope can narrow the field of view too much) and those wishing to capture it in an image are advised to set their camera to a manual exposure of around 3-4 seconds. Some pro-processing may be required to clean-up excess noise and bring out the colour, but with care, some great results can be achieved.
YouTube user “Spacemoive” put together a sees of images of the comet over the village of Spicheren, France, on July 7th to make a time-lapse film of the comet when it was still an early morning object, leading the sunrise.