looking back over April 2017 Space News looking back over April 2017

Hot Galaxies create a Hole in the CMB We think of the Cosmic Microwave Background (CMB) as the ‘residual heat’ from the Big Bang. However, there are much hotter things in the universe. In this picture, the hot gas in a cluster of galaxies results in a scattering of the photons from the CMB – hence the ‘hole’ in this picture, which suggests that this area is ‘cold’ with no CMB. This Sunyaev–Zel'dovich (SZ) effect has been used for a long time to reveal hot gas in clusters and identify new galaxies.

Commander Peggy sets new Space Record NASA astronaut and ISS Commander Peggy Whitson (57) broke the record for most time in Space by a NASA astronaut on April 24th. President Donald Trump called the ISS to congratulate her. She also holds the record for the most space- walking time (53h:22m in 8 ‘walks’) by a female astronaut. She is not due to return to Earth until September – by which date ~650 days in space!

China building its own Space Station China's Tianzhou-1 cargo spacecraft performed an automated docking with the country's orbiting Tiangong-2 space lab on Saturday April 22nd according to the Beijing Aerospace Command and Control Centre. The robotic Tianzhou-1 was launched on a Long March-7 Y2 rocket on April 20th from Wenchang Space Centre in China's Hainan province. Now Tianzhou-1 and Tiangong-2 have formed a rigid, combined unit to be extended in future to create a multi-unit space laboratory. Tiangong means “Heavenly Palace”.

Space Programmes on TV – Watch on iPlayer, etc. The Sky at Night 60th Anniversary Special BBC 4 The Moon ever since we landed there BBC 4 The Sun Its dark and stormy side BBC4 Seeing Stars The latest big telescopes BBC 2 The beginning and end of the Universe (2 progs) BBC 4 Note: Only available until ~ 20th May

A last look at Home… On April 12th, Cassini prepared to make its first close orbit of Saturn – between the planet and its rings. This view from within the shadow of Saturn gave this last look back at our home planet. A careful look may reveal the Moon, just to the left of Earth, 1.4 billion kilometres away.

Cassini – 1st Ring-Dive shows Atmosphere Effects Cassini spacecraft made its first of 22 passes between Saturn and its rings on April 26th. Data sent back on the day after confirmed that it had survived what could have been fatal at the speed it is travelling (77,000 mph) – even though the ring material is mostly dust and ice crystals. These rather crude first pictures show a large tornado-type storm, a few light fluffy clouds and thirdly what have been called ‘popcorn clouds’. To protect its cameras and sensors, the large antenna was pointed forwards as a shield during the dive. It was then necessary to wait while the antenna was oriented towards Earth for transmission of the data.

NASA gets new funding at last President Donald Trump has signed the NASA Transition Authorization Act of 2017, which sets a $19.5 billion budget for the agency for fiscal year 2017. Although this will keep NASA in business for the year ahead, it is likely that the 2018 and future budgets will be reduced, as space technology is to be transferred to more commercial companies. Several NASA projects currently in planning are likely to be dropped in favour of more dramatic ones like the new heavy lift rocket and the proposed manned mission to Mars.

Carbon Dioxide capture visible from Space CO2 capture is here visible on Earth. These swirls in the Black Sea are due to concentrations of phytoplankton, which cover their weak bodies with an armour of calcium carbonate, CaCO3. This has been happening for millions of years – hence limestone, chalk and marble rocks on earth, which hold many trillions of tons of carbon dioxide. Here in the black sea, more CO2 is being stored as CaCO3. There is no evidence that this process has ever occurred on Mars – which may be an indicator of the absence of life in ancient Martian seas.

Newly-found Comet seems to have died Comet C/2017 E4 (Lovejoy) was only discovered in March by noted comet discoverer Terry Lovejoy. The comet reached visual magnitude 7 earlier this month. However, the comet's nucleus appeared to be disintegrating and fading as it neared its closest approach to the Sun on 23rd April.

5 Moons and Jupiter On April 10th, the Full Moon and Jupiter shared this field of view. Both were near opposition, opposite the Sun in Earth's night sky. Jupiter continues to be very high and bright in the South during May. In this shot, a passing cloud- bank helped by dimming the Moon, giving this single photo showing 5 of the 6 largest satellites in the Solar System. Which one is missing?

What’s up there?? Geostationary Satellites

Talking Across the World Iridium Communication Satellites

All the New Stuff Last 30 Days Launches Application: Satellite Tracker for Android by Rotembo. Data: Nasa.gov

Danish “Space Agency” plans its own Moon-shot! From June you may be able to pick up your own Saturn V Apollo system for only $120. Danish scientists toy-designers have been working on this project for all of 3 years – much quicker than the NASA missions of the 1960s. The set includes 1,969 pieces, providing a link to the year that the Apollo 11 mission landed Neil Armstrong and Buzz Aldrin on July 20th to walk on the moon.

Send anything interesting you spot during April to: michael@held.org.uk