astronomy

TOI-4603 b

TOI-4603 b is a astronomy topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand TOI-4603 b rather than just read about it. In short: TOI-4603 b is a gas giant exoplanet orbiting HD 245134, a F-type subgiant star located 731 light-years away, in the constellation of Taurus. It orbits its host star at a distance of 0.0888 astronomical units (13,280,000 km), completing one orbit every 7 days around it.

Key takeaways

TOI-4603 b belongs to astronomy; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect TOI-4603 b to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of TOI-4603 b from memory before moving on to harder problems.

Reference excerpt

TOI-4603 b is a gas giant exoplanet orbiting HD 245134, a F-type subgiant star located 731 light-years away, in the constellation of Taurus. It orbits its host star at a distance of 0.0888 astronomical units (13,280,000 km), completing one orbit every 7 days around it. With a density of 14.1 g/cm3 (about 2.5 times that of Earth), it is one of the densest exoplanets known. The planet is just 4% larger than Jupiter, but is 12.9 times more massive, being located in the mass limit between planets and brown dwarfs.

Physical characteristics TOI-4603 b is similar to the planet Jupiter in size, being only 4% larger. Radial velocity measurements calculated the planet's mass to be 12.89+0.58−0.57 MJ meaning that the object is close to the mass limit between planets and brown dwarfs, which is usually set at 13 MJ. Its equilibrium temperature is calculated at 1,677 K (1,404 °C).

High density Combining the radius and mass, the density of TOI-4603 b is calculated to be 14.1+1.6−1.7 g/cm³, about 2.5 times greater than Earth's, making it one of the densest exoplanets known to date, and one of the most massive and dense transiting exoplanets known.

Orbital characteristics TOI-4603 b orbits its star at a distance of 0.0888 astronomical units (13,280,000 km), and completes one orbit every 7 days and 6 hours. The orbit of TOI-4603 b is very elliptical, having an orbital eccentricity of 0.325, which indicates that the planet is undergoing tidal migration due to a gravitational interaction with another planet. Kervella et al. (2019) found that a brown dwarf with a mass of 20.5 MJ is orbiting the system at a distance of around 1.8 AU, which may be influencing TOI-4603 b's orbit. A similar object is a planet called HATS-70b. It is less dense than TOI-4603 b, but similarly close to its star, and also shows signs of orbital migration.

Discovery NASA's Transiting Exoplanet Survey Satellite observed the host star TOI-4603 between September 16, 2021, and December 2, 2021. Afterwards, the group of astronomers led by Akanksha Khandelwal of the Physical Research Laboratory (PRL) in India, reported that a transit signal had been identified in the light curve of the star. Radial velocity measurements taken with the PARAS and TRES spectrographs confirmed the transit signal to be an exoplanet orbiting the star. It was the third exoplanet discovered by Indian astronomers, using the PARAS spectrograph and the PRL 1.2 m telescope. The discovery was announced in 2023.

Host star

HD 245134 (TOI-4603) is a F-type subgiant located 736 light-years away in the constellation of Taurus. It is well suited for the study of the Rossiter–McLaughlin effect and helpful for measuring the projected stellar obliquity of planets. The star has an apparent magnitude of 9.2, being too faint to be seen with the naked eye. It is a metal-rich star, with abundance of iron 2.2 times greater than that of the Sun.

Orbital companions HD 245134 is orbited by an exoplanet (TOI-4603 b), and by a 20.5 MJ brown dwarf star at a distance of 1.8 AU from the star.

Notes

References

Worked examples

Example 1 — a first encounter with TOI-4603 b

Start with the simplest possible case. Write down what TOI-4603 b claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In astronomy, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to TOI-4603 b before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about TOI-4603 b ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of TOI-4603 b

In research: TOI-4603 b appears in astronomy research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses TOI-4603 b in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: TOI-4603 b is common in secondary-school and first-year university syllabi. It links to neighbouring topics Exoplanets discovered by TESS, Exoplanets discovered in 2023, Hot Jupiters, so understanding it makes those chapters shorter.
In everyday life: Look for TOI-4603 b outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “TOI-4603 b” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study TOI-4603 b in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what TOI-4603 b means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain TOI-4603 b out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is TOI-4603 b in simple terms?

Why does TOI-4603 b matter?

Because it connects several astronomy ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study TOI-4603 b?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on TOI-4603 b.