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BAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 1
Why do hurricanes rotate anti-clockwise in the northern hemisphere and clockwise in the southern hemisphere?
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 2
Why are there two tides every day?
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 3
A typical cheap handheld telescope has a diameter of 10 cm, whilst ones for keen amateurs can have diameters of 40 cm. H...
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 4
Which of the following is not a zodiacal constellation, according to the astronomical definition?
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 5
When observing from the UK, during which season is the Full Moon visible highest in the sky?
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 6
Given an overwhelmingly large piece of paper, with a thickness of 10 μm, approximately how many times do you need to fol...
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 7
At a latitude of 52° N what is the altitude of Polaris above the horizon?
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 8
"Manhattanhenge" is the name given to when, just before sunset or just after sunrise 4 times a year (twice for setting,...
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 9
You travel 100 miles South, 100 miles East and 100 miles North and arrive back where you started. Where are you? You are...
Open questionBAAO — 2016 Astronomy & Astrophysics A2 Challenge
Question 10
On 5th September 2016, the Rosetta mission finally found the Philae lander on Comet 67P/Churyumov-Gerasimenko. Consideri...
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 1
In 2015, physicists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced the first-ever observati...
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 2
In which constellation would you find the centre of the Milky Way?
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 3
What is the approximate average thickness of Saturn's rings?
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 4
Pluto has roughly the same surface area as which country?
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 5
In the video game Halo, players are able to move around on the inner edge of a ring structure, which has a radius of 500...
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 6
What is the declination of the Sun on the Winter solstice?
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 7
Which of the following cities will experience the longest day during June?
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Question 8
If a planet orbits the Sun with a semi-major axis of 4 AU, what is the period of its orbit?
Open questionBAAO — 2017 Astronomy & Astrophysics Challenge
Questions 9–10
Two light sources, A and B, emitting their light isotropically (i.e. equally in all directions) are placed at distance r...
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 1
For a satellite in a circular orbit around the Earth, which of the arrows in the figure below describe the direction of...
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 2
The tail of a comet
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 3
Meteor showers are caused by
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 4
Looking up into the UK sky at 10pm in late September, which of the following bright stars is NOT visible?
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 5
The three stars that make up Orion's belt are Alnitak, Alnilam and Mintaka, with apparent magnitudes, m, of 1.77, 1.69 a...
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Questions 6–7
A comet is orbiting the Sun in an orbit with a semi-major axis of 5.0 au and an eccentricity, e = 0.80. Calculate its se...
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 8
On the evening of 27th July 2018, there was a total lunar eclipse (where the Moon passes into the Earth's shadow). As vi...
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 9
Light from a star is split into a line spectrum of different colours. The line spectrum from the star is shown, along wi...
Open questionBAAO — 2018 Astronomy & Astrophysics Challenge
Question 10
'Oumuamua is an elongated interstellar comet. During an observation with a ground-based telescope whilst close to the Su...
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 1
The image below was released in April 2019 by the Event Horizon Telescope collaboration and is considered to be one of t...
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 2
Where on the Moon did astronauts walk in July 1969?
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 3
The Chandra X-ray Observatory celebrates 20 years of operation this year, and was 100 times more sensitive than previous...
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 4
Looking up into the UK night sky in late September, which of the following bright stars rises first?
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 5
In May 1919 the British astronomers Frank Watson Dyson and Arthur Stanley Eddington organised for two teams to photograp...
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 6
An observer in the UK sees a full moon in the constellation of Capricorn. What time of year is it?
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 7
Earth’s moon has a radius of 1737 km and Titan (one of Saturn’s moons) has a radius of 2576 km. At the surface, their gr...
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 8
The One-Mile Telescope is a radio telescope just outside Cambridge that has three dishes that can be spread out up to on...
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 9
There are approximately 450 geostationary satellites currently in orbit. They have an orbital period of 1 day and orbit...
Open questionBAAO — 2019 Astronomy & Astrophysics Challenge
Question 10
On the 1st January 2019 the New Horizons probe (having successfully flown by Pluto in 2015) had an encounter with the Ku...
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 1
The year 1990 held many exciting events in astronomy. Which of the following did not celebrate its 30th anniversary this...
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 2
Which well-known star dropped in brightness by 40% between October 2019 and April 2020, leading to speculation it may be...
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 3
A very strong argument for the existence of dark matter is:
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 4
The Ring Nebula, M57, is surrounded by thin shells of out-flowing material, the outermost (and faintest) of which is mea...
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 5
Which of these constellations is entirely south of the ecliptic?
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 6
For an observer at a latitude of 52°, which of these stars culminates with the highest altitude?
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 7
On 21st March the Sun is in the constellation of Pisces. In which of these constellations would it be possible to find V...
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 8
When an exoplanet transits a star, the brightness of the star dims by 0.0557 magnitudes. Let Rₚ be the radius of the pla...
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 9
The event horizon of a non-spinning, uncharged black hole can be thought of as a sphere with a radius equal to the Schwa...
Open questionBAAO — 2020 Astronomy & Astrophysics Challenge
Question 10
On 19th July 2020 the first Arab interplanetary mission was launched on its way to Mars, consisting of the Hope probe de...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 1
As of September 2021, which of the following billionaires has not been into space (defined as at least 80 km above the s...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 2
The website what3words splits up the Earth’s surface into 3 m × 3 m squares and gives a co-ordinate of three randomly ch...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 3
After many delays, the James Webb Space Telescope (JWST) is due to be launched in December 2021. This will be the succes...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 4
For which of these lines of latitude will a vertical stick in the ground have no shadow at local midday on 21st December...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 5
When Mars has its opposition in 2022, an observer in the UK will see it in Taurus. In roughly which month will this oppo...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 6
In which constellation is Saturn visible during Autumn 2021? [Hint: it is close to Jupiter, which spent most of Summer 2...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 7
Which of these stars are closest to the Sun in October 2021?
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 8
Estimate the number of photons incident on a human pupil (of radius 2mm) from the Sun per second when it is at the zenit...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 9
A comet orbits the Sun with a period of 172 years and eccentricity 0.94. It is currently at a distance of 60 au away fro...
Open questionBAAO — 2021 Astronomy & Astrophysics Challenge
Question 10
In the rotating reference frame where the Earth is stationary, an asteroid orbits the Sun in 3.5 years. What is the dist...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 1
Below is one of the first images taken with the James Webb Space Telescope (JWST) released to the public on 12th July 20...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 2
In Autumn 2022, NASA plans to launch a practice mission in preparation for sending humans back to the Moon. What is the...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 3
A telescope with a focal length of 750 mm is used with an eyepiece. Which eyepiece focal length would give the greatest...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 4
The Gaia spacecraft, launched in 2013, is designed to map the sky with unprecedented precision. Its third data release (...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 5
In September 2022, Jupiter reached opposition a few days after the autumnal equinox. Which constellation was it in at th...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 6
An observer on the equator sees the Moon rise at 22:00. Ignoring the inclination and eccentricity of the Moon’s orbit, w...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 7
Which of these stars will culminate at the highest altitude as seen by an observer in Oxford (latitude 51.75° N, longitu...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 8
The cubesat CAPSTONE will enter a near-rectilinear halo orbit (NRHO) of the Moon on 13th November 2022 as a direct test...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 9
An asteroid in a circular orbit around the Sun is at its closest to Earth every 300 days. What is its orbital speed? Ass...
Open questionBAAO — 2022 Astronomy & Astrophysics Challenge
Question 10
Jupiter’s apparent magnitude at opposition in 2022 of m = −2.94 is the brightest for ∼ 70 years due to it happening clos...
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 1
SaxaVord is due to be one of the UK’s newest spaceports, with first launches planned in late 2023. Where is it based?
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 2
In a given system, for all circular orbits of period T and orbital speed v, which of the following quantities is the sam...
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 3
The recent supernova SN 2023ixf was one of the closest to Earth of the past decade, reaching an apparent magnitude of 10...
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 4
In August 2023, India became the fourth country to successfully land a spacecraft on the Moon. The Chandrayaan 3 mission...
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 5
From which of these settlements can a geostationary satellite not be seen?
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 6
What is the Messier number of this object?
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 7
Which of the following stars is in the constellation Taurus?
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 8
Which of these constellations contains the nearest (comparable size) galaxy to the Milky Way?
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 9
An observer in the UK sees a third quarter moon in the constellation Capricornus. What is the month?
Open questionBAAO — 2023 Astronomy & Astrophysics Challenge
Question 10
On the 21st June the Sun sets in Guernsey (49.45° N, 2.59° W) at 21:00 BST (British Summer Time, BST = UT+1). At what ti...
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 1
The year 2024 marks the 10th anniversary of the landing by which of the following spacecraft?
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 2
If the Moon appears to be exactly half illuminated by the Sun, what is the Sun-Earth-Moon angle, assuming the Earth and...
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 3
Using Hubble’s law for recessional velocities of distant objects, find a possible expression to estimate the recessional...
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 4
T Coronae Borealis (T CrB), nicknamed the Blaze Star, is a binary star system about 920 pc away in the constellation Cor...
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 5
The Euclid space mission, launched in 2023, will image 36% of the sky in extremely high resolution to investigate the na...
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 6
An observer is lost at sea and sees that Polaris is 33° above the horizon. What is their latitude?
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 7
Which of the following constellations is south of the celestial equator?
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 8
Which of the following Messier objects is a nebula that can be found in the same constellation as the star Aldebaran?
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 9
Which of these stars will culminate at the highest altitude, as seen by an observer in Rio de Janeiro (22.91° S, 43.17°...
Open questionBAAO — 2024 Astronomy & Astrophysics Challenge
Question 10
Between September 2024 and January 2025, Mars, Saturn, Uranus, and Neptune will all be in opposition: Mars in Gemini, Sa...
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