From January 25 to February 8, 2021

Mercury is visible in the evening sky where it’s undergoing a very good apparition until January 31: Look for Mercury a few degrees above the southwest horizon, 30 to 45 minutes after sunset. At the beginning of February, the tiny planet vanishes in the glare of the sun and passes in inferior conjunction (between Earth and the sun) on February 8.

Venus is too close to the sun and is not currently visible. The planet passes on the far side of the sun (superior conjunction) on March 26, and will gradually reappear as the bright Evening Star after mid-April.

Mars is receding from Earth, but it’s still remarkably bright. The Red Planet appears at dusk about 60 degrees high in the south and sets in the west-northwest after 1:00 a.m. During the evening of February 18, the thick crescent Moon comes within 3½ degrees to the south of Mars.

Jupiter is now too close to the Sun and is lost in our star’s glare. The Giant Planet passes behind the Sun (conjunction) on January 28 and will reappear at dawn in late-February.

Saturn is now too close to the Sun and is lost in our star’s glare. The Ringed Planet passed behind the Sun (conjunction) on January 23 and will reappear at dawn after mid-February.

From February 8 to 22, 2021

Mercury passes in inferior conjunction (between Earth and the sun) on February 8 and is not visible. The tiny planet then emerges in the morning sky where it undergoes a poor apparition: Between February 25 and March 10, look for Mercury very low in the south-southeast, 30 minutes before sunrise.

Venus is too close to the sun and is not currently visible. The planet passes on the far side of the sun (superior conjunction) on March 26, and will gradually reappear as the bright Evening Star after mid-April.

Mars is receding from Earth, and although its brightness has decreased a lot since opposition last October, it’s still fairly bright. The Red Planet appears at dusk about 63 degrees high in the south and sets in the west-northwest after 12:30 a.m. During the evening of February 18, the thick crescent Moon comes within 3½ degrees to the south of Mars.

Jupiter is now too close to the Sun and is lost in our star’s glare. The Giant Planet passes behind the Sun (conjunction) on January 28 and will reappear at dawn in late-February.

Saturn passed behind the Sun (conjunction) on January 23 and will reappear at dawn after mid-February: Look for Saturn very low in the east-southeast, 45 minutes before sunrise. The Ringed Planet is gradually pulling away from the Sun and appears higher in the sky, thus becoming easier to spot in a darker sky with each passing day.

Why do some plants produce small flowers unlikely to attract pollinators?

When people talk about flowers, they usually talk about ones with bright, contrasting, shimmering colours. Yet not all plants produce only those kinds of flowers. Cleistogamous species can produce two types of flowers on the same plant: “normal” ones that look great, but also “runts” that are small and never open. This second category of flowers don’t need to lure pollinating insects by using colours and smells because they pollinate themselves.

In a recent study, Jardin botanique de Montréal botanist Simon Joly and McGill University biology professor Daniel Schoen show that cleistogamy, as this type of self-pollination is called, is strongly associated with flowers having bilateral symmetry, meaning that they have a single place of symmetry, rather than multiple ones; orchids are a good example of bilateral flower symmetry.

Reproductive failure

Flowers generally have both male and female reproductive organs, which, for a sedentary organism, is an effective evolutionary strategy to ensure reproduction. By offering a reward such as nectar or pollen, flowers help plants entice animal pollinators to carry pollen between plants of the same species, effectively acting as intermediaries in the mating process.

The problem with this strategy is that if there are no pollinators, the plant may fail to reproduce or may have less success doing so. Cleistogamy is a way of getting round this problem. While somewhat rare, this reproductive strategy is nevertheless used by over 500 species from some 40 flowering plant families, including jewelweeds and violets. Cleistogamy often goes unnoticed, however, as cleistogamous flowers are so small.

Darwin was right

Darwin was well aware of the advantages of cleistogamy as a reproductive strategy and he hypothesized that it is more likely to occur in species with bilateral flower symmetry than in species with radial flower symmetry (which have several planes of symmetry, such as apple blossoms). This is the case because plant species with bilateral flower symmetry are normally pollinated by fewer species of insects than species with radially symmetric flowers.

Until now, however, this hypothesis of Darwin’s on the association between cleistogamy and bilateral symmetry had never been properly tested.

To test Darwin’s hypothesis, Simon Joly and Daniel Schoen analysed over 2,500 species of flowering plants—the biggest dataset ever assembled for flowers featuring these unusual characteristics. As a result, they were able to show that cleistogamy evolves much more frequently in plants having bilateral flower symmetry, thus confirming the hypothesis Darwin posited 150 years ago based on his study of just a few dozen species!

The paper “Repeated evolution of a reproductive polyphenism in plants is strongly associated with bilateral flower symmetry,” by Simon Joly, a botanist at the Jardin botanique de Montréal and a professor of biology at the Université de Montréal, and Daniel Schoen, a professor of biology at McGill University, was published in the journal Current Biology on February 3, 2021.

From February 22 to March 8, 2021

Mercury passed in inferior conjunction (between Earth and the sun) on February 8 and undergoes a poor apparition in the morning sky between February 25 and March 10. Look for the tiny planet very low in the south-southeast, 30 minutes before sunrise.

Venus is too close to the sun and is not currently visible. The planet passes on the far side of the sun (superior conjunction) on March 26, and will gradually reappear as the bright Evening Star after mid-April.

Mars is receding from Earth, and although its brightness has decreased a lot since opposition last October, it’s still fairly bright. The Red Planet appears at dusk about 60 degrees high in the southwest and sets in the west-northwest around 12:30 a.m. On the evening of March 3, the Red Planet shines 2½ degrees below the Pleiades star cluster; from March 6 to 10, it passes between the Hyades and the Pleiades. During the evening of March 19, the thick crescent Moon hangs 3 degrees to the left of Mars.

Jupiter passed behind the Sun (conjunction) on January 28 and reappears at dawn in late-February. Look for the Giant Planet very low in the east-southeast, 30 minutes before sunrise. Jupiter is gradually pulling away from the Sun and appears higher in the sky each day, thus becoming easier to spot against a darker sky.

Saturn passed behind the Sun (conjunction) on January 23 and will reappear at dawn after mid-February: Look for Saturn very low in the east-southeast, 45 minutes before sunrise. The Ringed Planet is gradually pulling away from the Sun and appears higher in the sky each day, thus becoming easier to spot against a darker sky.

The Insectarium de Montréal is home to a whole team of insect enthusiasts! Two of these experts are Stéphane Le Tirant and Royce T. Cumming, who set up a rather unusual team four years ago: Team Phyllie. The two researchers decided to focus on the leaf insect family: the Phylliidae. 

Their fascination with Phylliidae enabled a giant step to be taken in the study of leaf insects, with the discovery and description of new species. The team has acquired significant expertise, describing 27 new species, out of 100 known species in the world. The most recent achievement was the review of the celebicum group, which led to the description of a new genus and 13 new species! 

Leaf insects mimic leaves perfectly, and individuals look very much alike. To differentiate the various species, a number of steps had to be taken, partly involving traditional means such as physical description, but also genetic analysis and the study of eggs and larvae right from the initial stages. 

International cooperation between researchers in the United States, Germany, Belgium, China and Canada was crucial to the success of the research.

Something to discover when the Insectarium reopens

A number of types will be added to the Insectarium’s scientific collection, making the institution the world’s leading collector of Phylliidae. Included in the collection are two new species dedicated to Quebecers: Cryptophyllium limogesi, whose name pays tribute to Insectarium technician René Limoges and his photographs of insects, and Cryptophyllium bankoi, named in honour of Alexandre Banko, a long-standing collaborator and former guide at the Insectarium. 

The article Cryptophyllium, the hidden leaf insects – descriptions of a new leaf insect genus and thirteen species from the former celebicum species group (Phasmatodea, Phylliidae), written by Insectarium associate researcher Royce T. Cumming and Insectarium scientific collection curator Stéphane Le Tirant, along with six others, was published on February 18, 2021, in the scientific journal ZooKeys.

From March 8 to 22, 2021

Mercury is at the end of a poor apparition in the morning sky. Until March 10, look for the tiny planet very low in the south-southeast, 30 minutes before sunrise; after mid-March, Mercury vanishes in the sun’s glare. It passes in inferior conjunction (behind the sun) on April 18 and will reappear in the evening sky later this spring.

Venus is too close to the sun and is not currently visible. The planet passes on the far side of the sun (superior conjunction) on March 26, and will gradually reappear as the bright Evening Star after mid-April.

Mars is receding from Earth, and although its brightness has decreased a lot since opposition last October, it’s still fairly bright. The Red Planet appears at dusk about 60 degrees high in the southwest and sets in the west-northwest around 12:30 a.m. (Standard Time). From March 6 to 10, the Red Planet passes between the Hyades and the Pleiades. During the evening of March 19, the thick crescent Moon hangs 3 degrees to the left of Mars.

Jupiter is now visible at dawn: Look for the Giant Planet very low in the east-southeast, 45 minutes before sunrise. Jupiter is gradually pulling away from the Sun and appears higher in the sky each day, thus becoming easier to spot against a darker sky.

Saturn is now visible at dawn: Look for Saturn very low in the east-southeast, 60 minutes before sunrise, about ten degrees to the right of very bright Jupiter. The Ringed Planet is gradually pulling away from the Sun and appears higher in the sky each day, thus becoming easier to spot against a darker sky.

From March 22 to April 5, 2021

Mercury is presently too close to the sun and is not visible. The tiny planet passes in inferior conjunction (behind the sun) on April 18 and will reappear in the evening sky a few days later.

Venus is too close to the sun and is not currently visible. The planet passes on the far side of the sun (superior conjunction) on March 26, and will gradually reappear as the bright Evening Star after mid-April.

Mars is receding from Earth, and although its brightness has decreased a lot since opposition last October, it’s still fairly bright. The Red Planet appears at dusk about 55 degrees high in the west-southwest, a few degrees above bright star Aldebaran. Mars sets in the west-northwest around 1:00 a.m. The crescent Moon shines near Mars on the evenings of April 16 and 17.

Jupiter is now easily visible at dawn: The Giant Planet emerges in the east-southeast more than an hour before sunrise. Jupiter is gradually pulling away from the Sun and appears higher in the sky each day, thus becoming easier to spot against a darker sky. On the morning of April 7, the waning crescent Moon passes 5 degrees below Jupiter.

Saturn is now visible at the end of the night and at dawn: Look for Saturn very low in the east-southeast, more than 90 minutes before sunrise. During dawn, Saturn shines about ten degrees to the right of very bright Jupiter. The Ringed Planet is gradually pulling away from the Sun and appears higher in the sky each day, thus becoming easier to spot against a darker sky. On the morning of April 6, the waning crescent Moon hangs 4½ degrees below Saturn.

From April 5 to 19, 2021

Mercury is presently too close to the sun and is not visible. The tiny planet passes in inferior conjunction (behind the sun) on April 18 and will reappear in the evening sky a few days later.

Venus is too close to the sun and is not currently visible. The planet passed on the far side of the sun (superior conjunction) on March 26, and will gradually reappear as the bright Evening Star after mid-April.

Mars is receding from Earth, and although its brightness has decreased a lot since opposition last October, it’s still fairly bright. The Red Planet appears at dusk about 50 degrees high in the west-southwest, and about 15 degrees above bright star Aldebaran. Mars sets in the west-northwest around 1:00 a.m. The crescent Moon shines near Mars on the evenings of April 16 and 17.

Jupiter is now easily visible at the end of the night and at dawn: The Giant Planet emerges in the east-southeast about two hours before sunrise. At dawn, it shines a dozen degrees above the southeast horizon. On the morning of April 7, the waning crescent Moon passes 5 degrees below Jupiter.

Saturn is now visible at the end of the night and at dawn. Look for Saturn very low in the east-southeast, about two and a half hours before sunrise. During dawn, Saturn shines some 15 degrees above the southeast horizon, a dozen degrees to the right of very bright Jupiter. On the morning of April 6, the waning crescent Moon hangs 4½ degrees below Saturn.

From April 19 to May 3, 2021

Mercury passed through superior conjunction (behind the sun) on April 18 and will reappear in the evening sky a few days later. From late-April until about May 20, you’ll be able to spot the tiny planet 30 minutes after sunset, low in the west-northwest.

Venus passed on the far side of the sun (superior conjunction) on March 26, and gradually reappears as the bright Evening Star, very low in the west-northwest, 30 minutes after sunset. Fainter Mercury is also visible a few degrees above Venus.

Mars is receding from Earth, and although its brightness has decreased a lot since opposition last October, it’s still fairly bright. The Red Planet appears at dusk about 40 degrees high in the west, and more than 20 degrees to the left of bright star Capella. Mars sets in the northwest around 12:30 a.m. The thin crescent Moon comes within 1 ½ degrees of Mars on the evening of May 15.

Jupiter is easily visible at the end of the night and at dawn: The Giant Planet emerges in the east-southeast about two hours before sunrise. At dawn, it shines 15 degrees above the southeast horizon. On the mornings of May 4 and 5, the waning crescent Moon hangs near Jupiter.

Saturn is visible at the end of the night and at dawn. Look for Saturn very low in the east-southeast, about two and a half hours before sunrise. During dawn, Saturn shines some 18 degrees above the southeast horizon, about 15 degrees to the right of very bright Jupiter. On the morning of May 3, the last quarter Moon approaches within 7 degrees of Saturn.

From May 3 to 17, 2021

Mercury is presently making a fine apparition in the evening sky. Look for the tiny planet at dusk, 45 minutes after sunset, low in the west-northwest, a few degrees above much brighter Venus. Mercury is brighter at the beginning of this period, and dims rapidly after mid-month; it should remain easily visible until about May 20, before plunging back between Earth and the Sun. On May 3 and 4, Mercury shines about 2 degrees from the Pleiades star cluster. On the evening of May 13, the thin crescent moon hangs 3 degrees left of Mercury.

Venus is the bright Evening Star that shines very low in the west-northwest, 30 minutes after sunset. Fainter Mercury is also visible a few degrees above Venus. On the evening of May 12, the very thin crescent moon is just one degree to the left of Venus.

Mars is receding from Earth, and although its brightness has decreased a lot since opposition last October, it’s still fairly bright. The Red Planet appears at dusk about 35 degrees high in the west, and more than 25 degrees to the left of bright star Capella. Mars sets in the northwest around midnight. The thin crescent Moon comes within 1 ½ degrees of Mars on the evening of May 15.

Jupiter is easily visible at the end of the night and at dawn: The Giant Planet emerges in the east-southeast about two and a half hours before sunrise. At dawn, it shines brightly 20 degrees above the southeast horizon. On the mornings of May 4 and 5, the waning crescent Moon hangs near Jupiter.

Saturn is visible at the end of the night and at dawn. Look for Saturn very low in the east-southeast, about three hours before sunrise. During dawn, Saturn shines some 22 degrees above the south-southeast horizon, about 15 degrees to the right of very bright Jupiter. On the morning of May 3, the last quarter Moon approaches within 7 degrees of Saturn.