Earth observation: Launches Gone, Launches Due & Launches Planned

Artist's rendition of a satellite - 3dsculptor/123RF Stock Photo

Artist’s rendition of a satellite – 3dsculptor/123RF Stock Photo

September is a busy month for Earth observation satellites, and so here is a round-up of the month.

Launches Gone
The Indian Space Research Agency (ISRA) launched the INSAT-3DR weather satellite on September 8th into a geostationary orbit. It carries a multi-spectral imager capable of collecting data in six wavebands: visible, shortwave and midwave infrared, water vapour and two thermal bands. Taking an image every 26 minutes it will be used to monitor cloud patterns and storm systems, collecting data about outgoing longwave radiation, precipitation estimates, Sea Surface Temperature (SST), snow cover and wind speeds.

The second major launch took place on September 15th, from Europe’s Space Centre in French Guiana, when five new Earth observation satellites were put into orbit.

  • Four of these satellites, SkySats 4, 5, 6 & 7, were launched for the commercial company Terra Bella – which is owned by Google. It’s reported that they have informally named these satellites after the Star Wars characters: R2D2, Luke, C3PO and Leia! These small satellites provide 90 cm resolution for panchromatic images and 2 m for visible and near infrared wavebands. They also offer video acquired at 30 frames per second with a resolution of 1.1 m.
  • In addition, this launch brought a new country into the Earth Observation satellite owning family, as Peru launched PeruSAT-1 which will be operated by their military authorities. This satellite is in a 695 km sun-synchronous low Earth orbit and will provide imagery in the visible light wavebands with a 70 cm resolution. The data is expected to help study forest health, monitor illegal logging and gold mining, and provide support with natural disasters. However, the details of who can access to the data, the cost and how to access it are still to be made public.

Launches to Come
Last week we said DigitalGlobe’s WorldView-4 satellite was due to launch on the Friday. The problem of having a blog go live before an event means you can be wrong, and on this occasion we were! Friday’s launch was postponed for two days due to a leak during the propellant loading. Unfortunately, a wildfire then broke out near the Vandenburg Air Force base, and the launch had to be postponed a second time. It is hoped it will go ahead before the end of the month.

Following on from INSAT-3DR, ISRA is due to launch another four satellites in the last week of September including:

  • India’s ScatSat, a replacement for the Oceansat-2. Carrying OSCAT (OceanSat-2 Scanning Scatterometer) it will offer data related to weather forecasting, sea surface winds, cyclone prediction and tracking satellite. The data collected will be used by organisations globally including NASA, NOAA and EUMETSAT.
  • A second Earth observation satellite on the launch is Algeria’s first CubeSat – AlSat Nano. It was designed and built at the Surry Space Centre by Algerian Graduate students, as part of joint programme between the UK Space Agency and the Algerian Space Agency. It will carry a camera, magnetometer and will be testing an innovative solar cell which is one tenth of a millimetre thick.

Launches Being Planned
The next country to join the Earth Observation community could well be North Korea. It was reported this week that they had carried out a successful ground test of a new rocket engine which would give them the capacity to launch various satellites, including Earth Observation ones.

Airbus Defence and Space also announced plans this week for four Earth observation satellites to be launched in 2020 and 2021. These will provide very high resolution imagery and continuity for the existing two Pléiades satellites.

As we’ve previously discussed, the trend in launches continues apace for the Earth observation community.

Did you know remote sensing goes extra-terrestrial?

Ceres captured by NASA's Dawn spacecraft on 19 Feb 2015. Image courtesy NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Ceres captured by NASA’s Dawn spacecraft on 19 Feb 2015.
Image courtesy NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

If you didn’t realise remote sensing of other planets and space objects occurs, you’re not alone. Remote sensing is playing an important role in helping us understand how our planet, and our universe, was created; however this isn’t celebrated much outside, or even within, the remote sensing community. We discussed this topic when ESA’s Rosetta arrived at Comet 67P, and it surfaced again last week when NASA’s Dawn spacecraft went into orbit around the dwarf planet, Ceres, which lies 38 000 miles away, between Mars and Jupiter.

Dawn’s mission is to study Ceres and the asteroid Vesta, which it orbited during 2011 and 2012, to develop our understanding of early solar system formation. There was a lot of media attention about Dawn’s arrival at Ceres, as it’s the first spacecraft to visit a dwarf planet and also the first to orbit two different non-earth objects. The technical and engineering feat to get Dawn to Vesta and Ceres is amazing, but the science to acquire, and interpret, the data is pure remote sensing. However, you rarely see it described as such within the headlines.

Dawn carries three scientific instruments:

  1. A camera, designed by the Max Planck Institute for Solar System Research in Germany, which will provide both three colour and panchromatic images, and when it descends into a low orbit around Ceres it will offer 62m spatial resolution. It can use 7 different colour filters, detect near-infrared energy and has an 8 gigabyte internal memory. As the camera is vital to both the navigation, and the science, side of the mission, Dawn carries two identical, but physically separate, versions.
  2. A Visible and Infrared Mapping Spectrometer (VIR-MS) designed and built by Galileo Avionica in Italy to provide surface maps. The instrument has a high spectral resolution of between 0.25 – 1µm in the visible light range, and 0.95 – 5µm in infrared, and has 6 gigabits of internal memory. Interestingly, it was based on the VIRTIS instrument carried by Rosetta to map Comet 67P.
  3. Gamma Ray and Neutron Detector (GRaND) — The instrument has 21 sensors, a wide field of view and produces maps of Ceres measuring the rock forming elements, trace elements, radioactive elements as well as Hydrogen, Carbon and Nitrogen. It was developed by the Los Alamos National Laboratory in the United States, and unlike the other two instruments has no internal storage.

Supporting these instrument measurements will be various radiometric and navigational data to help determine the gravitational field. The fundamental principles of remote sensing – measuring the reflected energy of the planet to determine what is on the surface – is right at the heart of Dawn’s mission. So why isn’t the remote sensing community shouting more about it?

We’re probably as guilty as everyone else here; we refer to Pixalytics as either a remote sensing company and/or an Earth observation company. Is it this association to Earth, which means we don’t always acknowledge the work, and achievements, beyond our planet?

Remote sensing is leading the way in enhancing knowledge about how the universe began; this is our scientific field that is helping make this possible. So let’s make some noise for the remote sensing community, elbow the space engineers out of the way to get ourselves into the news and let everybody else know what remote sensing can do!